RNA recognition motif (RRM) found in RNA-binding protein with serine-rich domain 1 (RNPS1) and similar proteins; This subfamily corresponds to the RRM of RNPS1 and its eukaryotic homologs. RNPS1, also termed RNA-binding protein prevalent during the S phase, or SR-related protein LDC2, was originally characterized as a general pre-mRNA splicing activator, which activates both constitutive and alternative splicing of pre-mRNA in vitro.It has been identified as a protein component of the splicing-dependent mRNP complex, or exon-exon junction complex (EJC), and is directly involved in mRNA surveillance. Furthermore, RNPS1 is a splicing regulator whose activator function is controlled in part by CK2 (casein kinase II) protein kinase phosphorylation. It can also function as a squamous-cell carcinoma antigen recognized by T cells-3 (SART3)-binding protein, and is involved in the regulation of mRNA splicing. RNPS1 contains an N-terminal serine-rich (S) domain, a central RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and the C-terminal arginine/serine/proline-rich (RS/P) domain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 58865358 163 VHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVERMhPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEITAT 236
Cdd:cd12365   1 LHVGKLTRNVTKDHLKEIFSVYGTVKNVDLPIDRE-PNLPRGYAYVEFESPEDAEKAIKHMDGGQIDGQEVTVE 73

RNA recognition motif (RRM) found in RNA-binding protein with serine-rich domain 1 (RNPS1) and similar proteins; This subfamily corresponds to the RRM of RNPS1 and its eukaryotic homologs. RNPS1, also termed RNA-binding protein prevalent during the S phase, or SR-related protein LDC2, was originally characterized as a general pre-mRNA splicing activator, which activates both constitutive and alternative splicing of pre-mRNA in vitro.It has been identified as a protein component of the splicing-dependent mRNP complex, or exon-exon junction complex (EJC), and is directly involved in mRNA surveillance. Furthermore, RNPS1 is a splicing regulator whose activator function is controlled in part by CK2 (casein kinase II) protein kinase phosphorylation. It can also function as a squamous-cell carcinoma antigen recognized by T cells-3 (SART3)-binding protein, and is involved in the regulation of mRNA splicing. RNPS1 contains an N-terminal serine-rich (S) domain, a central RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and the C-terminal arginine/serine/proline-rich (RS/P) domain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 58865358 163 VHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVERMhPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEITAT 236
Cdd:cd12365   1 LHVGKLTRNVTKDHLKEIFSVYGTVKNVDLPIDRE-PNLPRGYAYVEFESPEDAEKAIKHMDGGQIDGQEVTVE 73

RNA recognition motif. (a.k.a. RRM, RBD, or RNP domain); The RRM motif is probably diagnostic of an RNA binding protein. RRMs are found in a variety of RNA binding proteins, including various hnRNP proteins, proteins implicated in regulation of alternative splicing, and protein components of snRNPs. The motif also appears in a few single stranded DNA binding proteins. The RRM structure consists of four strands and two helices arranged in an alpha/beta sandwich, with a third helix present during RNA binding in some cases The C-terminal beta strand (4th strand) and final helix are hard to align and have been omitted in the SEED alignment The LA proteins have an N terminal rrm which is included in the seed. There is a second region towards the C terminus that has some features characteriztic of a rrm but does not appear to have the important structural core of a rrm. The LA proteins are one of the main autoantigens in Systemic lupus erythematosus (SLE), an autoimmune disease.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 58865358   165 IGRLTRNVTKDHIMEIFSTYGKIKMIDMPveRMHPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEIT 234
Cdd:pfam00076   3 VGNLPPDTTEEDLKDLFSKFGPIKSIRLV--RDETGRSKGFAFVEFEDEEDAEKAIEALNGKELGGRELK 70

polyadenylate binding protein, human types 1, 2, 3, 4 family; These eukaryotic proteins recognize the poly-A of mRNA and consists of four tandem RNA recognition domains at the N-terminus (rrm: pfam00076) followed by a PABP-specific domain (pfam00658) at the C-terminus. The protein is involved in the transport of mRNA's from the nucleus to the cytoplasm. There are four paralogs in Homo sapiens which are expressed in testis, platelets, broadly expressed and of unknown tissue range.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 58865358   149 KERKRRSPSPKPTKVHIGRLTRNVTKDHIMEIFSTYGKIkmIDMPVERMHPHLSKGYAYVEFENPDEAEKALKHMDGGQI 228
Cdd:TIGR01628 167 KHEREAAPLKKFTNLYVKNLDPSVNEDKLRELFAKFGEI--TSAAVMKDGSGRSRGFAFVNFEKHEDAAKAVEEMNGKKI 244

                  ..
gi 58865358   229 DG 230
Cdd:TIGR01628 245 GL 246

RNA recognition motif (RRM) found in RNA-binding protein with serine-rich domain 1 (RNPS1) and similar proteins; This subfamily corresponds to the RRM of RNPS1 and its eukaryotic homologs. RNPS1, also termed RNA-binding protein prevalent during the S phase, or SR-related protein LDC2, was originally characterized as a general pre-mRNA splicing activator, which activates both constitutive and alternative splicing of pre-mRNA in vitro.It has been identified as a protein component of the splicing-dependent mRNP complex, or exon-exon junction complex (EJC), and is directly involved in mRNA surveillance. Furthermore, RNPS1 is a splicing regulator whose activator function is controlled in part by CK2 (casein kinase II) protein kinase phosphorylation. It can also function as a squamous-cell carcinoma antigen recognized by T cells-3 (SART3)-binding protein, and is involved in the regulation of mRNA splicing. RNPS1 contains an N-terminal serine-rich (S) domain, a central RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and the C-terminal arginine/serine/proline-rich (RS/P) domain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 58865358 163 VHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVERMhPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEITAT 236
Cdd:cd12365   1 LHVGKLTRNVTKDHLKEIFSVYGTVKNVDLPIDRE-PNLPRGYAYVEFESPEDAEKAIKHMDGGQIDGQEVTVE 73

RNA recognition motif;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 58865358    162 KVHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVERMHpHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEIT 234
Cdd:smart00360   1 TLFVGNLPPDTTEEELRELFSKFGKVESVRLVRDKET-GKSKGFAFVEFESEEDAEKALEALNGKELDGRPLK 72

RNA recognition motif (RRM) found in serine/arginine-rich splicing factor 3 (SRSF3) and similar proteins; This subfamily corresponds to the RRM of two serine/arginine (SR) proteins, serine/arginine-rich splicing factor 3 (SRSF3) and serine/arginine-rich splicing factor 7 (SRSF7). SRSF3, also termed pre-mRNA-splicing factor SRp20, modulates alternative splicing by interacting with RNA cis-elements in a concentration- and cell differentiation-dependent manner. It is also involved in termination of transcription, alternative RNA polyadenylation, RNA export, and protein translation. SRSF3 is critical for cell proliferation, and tumor induction and maintenance. It can shuttle between the nucleus and cytoplasm. SRSF7, also termed splicing factor 9G8, plays a crucial role in both constitutive splicing and alternative splicing of many pre-mRNAs. Its localization and functions are tightly regulated by phosphorylation. SRSF7 is predominantly present in the nuclear and can shuttle between nucleus and cytoplasm. It cooperates with the export protein, Tap/NXF1, helps mRNA export to the cytoplasm, and enhances the expression of unspliced mRNA. Moreover, SRSF7 inhibits tau E10 inclusion through directly interacting with the proximal downstream intron of E10, a clustering region for frontotemporal dementia with Parkinsonism (FTDP) mutations. Both SRSF3 and SRSF7 contain a single N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal RS domain rich in serine-arginine dipeptides. The RRM domain is involved in RNA binding, and the RS domain has been implicated in protein shuttling and protein-protein interactions.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 58865358 162 KVHIGRLTRNVTKDHIMEIFSTYGKIKmiDMPVERMHPhlskGYAYVEFENPDEAEKALKHMDGGQIDGQEIT 234
Cdd:cd12373   1 KVYVGNLGPRVTKRELEDAFEKYGPLR--NVWVARNPP----GFAFVEFEDPRDAEDAVRALDGRRICGSRVR 67

RNA recognition motif (RRM) found in heterogeneous nuclear ribonucleoprotein C (hnRNP C)-related proteins; This subfamily corresponds to the RRM in the hnRNP C-related protein family, including hnRNP C proteins, Raly, and Raly-like protein (RALYL). hnRNP C proteins, C1 and C2, are produced by a single coding sequence. They are the major constituents of the heterogeneous nuclear RNA (hnRNA) ribonucleoprotein (hnRNP) complex in vertebrates. They bind hnRNA tightly, suggesting a central role in the formation of the ubiquitous hnRNP complex; they are involved in the packaging of the hnRNA in the nucleus and in processing of pre-mRNA such as splicing and 3'-end formation. Raly, also termed autoantigen p542, is an RNA-binding protein that may play a critical role in embryonic development. The biological role of RALYL remains unclear. It shows high sequence homology with hnRNP C proteins and Raly. Members of this family are characterized by an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal auxiliary domain. The Raly proteins contain a glycine/serine-rich stretch within the C-terminal regions, which is absent in the hnRNP C proteins. Thus, the Raly proteins represent a newly identified class of evolutionarily conserved autoepitopes.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 58865358 162 KVHIGRL-TRNVTKDHIMEIFSTYGKIKMIdmpveRMHphlsKGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12341   2 RIFVGNLpTDQMTKEDLEEIFSKYGKILGI-----SLH----KGYGFVQFDNEEDARAAVAGENGRTIKGQRL 65

RNA recognition motif (RRM) found in cyclophilin-33 (Cyp33) and similar proteins; This subfamily corresponds to the RRM of Cyp33, also termed peptidyl-prolyl cis-trans isomerase E (PPIase E), or cyclophilin E, or rotamase E. Cyp33 is a nuclear RNA-binding cyclophilin with an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal PPIase domain. Cyp33 possesses RNA-binding activity and preferentially binds to polyribonucleotide polyA and polyU, but hardly to polyG and polyC. It binds specifically to mRNA, which can stimulate its PPIase activity. Moreover, Cyp33 interacts with the third plant homeodomain (PHD3) zinc finger cassette of the mixed lineage leukemia (MLL) proto-oncoprotein and a poly-A RNA sequence through its RRM domain. It further mediates downregulation of the expression of MLL target genes HOXC8, HOXA9, CDKN1B, and C-MYC, in a proline isomerase-dependent manner. Cyp33 also possesses a PPIase activity that catalyzes cis-trans isomerization of the peptide bond preceding a proline, which has been implicated in the stimulation of folding and conformational changes in folded and unfolded proteins. The PPIase activity can be inhibited by the immunosuppressive drug cyclosporin A.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 58865358 163 VHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVErMHPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEIT 234
Cdd:cd12347   1 LYVGGLAEEVDEKVLHAAFIPFGDIVDIQIPLD-YETEKHRGFAFVEFEEAEDAAAAIDNMNESELFGRTIR 71

RNA recognition motif 1 (RRM1) found in (U)-binding-splicing factor PUF60 and similar proteins; This subfamily corresponds to the RRM1 of PUF60, also termed FUSE-binding protein-interacting repressor (FBP-interacting repressor or FIR), or Ro-binding protein 1 (RoBP1), or Siah-binding protein 1 (Siah-BP1). PUF60 is an essential splicing factor that functions as a poly-U RNA-binding protein required to reconstitute splicing in depleted nuclear extracts. Its function is enhanced through interaction with U2 auxiliary factor U2AF65. PUF60 also controls human c-myc gene expression by binding and inhibiting the transcription factor far upstream sequence element (FUSE)-binding-protein (FBP), an activator of c-myc promoters. PUF60 contains two central RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal U2AF (U2 auxiliary factor) homology motifs (UHM) that harbors another RRM and binds to tryptophan-containing linear peptide motifs (UHM ligand motifs, ULMs) in several nuclear proteins. Research indicates that PUF60 binds FUSE as a dimer, and only the first two RRM domains participate in the single-stranded DNA recognition.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 58865358 162 KVHIGRLTRNVTKDHIMEIFSTYGKIKMIDM---PVERMHphlsKGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12370   2 RVYVGSIYFELGEDTIRQAFAPFGPIKSIDMswdPVTMKH----KGFAFVEYEVPEAAQLALEQMNGVMLGGRNI 72

RNA recognition motif 2 (RRM2) found in squamous cell carcinoma antigen recognized by T-cells 3 (SART3) and similar proteins; This subfamily corresponds to the RRM2 of SART3, also termed Tat-interacting protein of 110 kDa (Tip110), is an RNA-binding protein expressed in the nucleus of the majority of proliferating cells, including normal cells and malignant cells, but not in normal tissues except for the testes and fetal liver. It is involved in the regulation of mRNA splicing probably via its complex formation with RNA-binding protein with a serine-rich domain (RNPS1), a pre-mRNA-splicing factor. SART3 has also been identified as a nuclear Tat-interacting protein that regulates Tat transactivation activity through direct interaction and functions as an important cellular factor for HIV-1 gene expression and viral replication. In addition, SART3 is required for U6 snRNP targeting to Cajal bodies. It binds specifically and directly to the U6 snRNA, interacts transiently with the U6 and U4/U6 snRNPs, and promotes the reassembly of U4/U6 snRNPs after splicing in vitro. SART3 contains an N-terminal half-a-tetratricopeptide repeat (HAT)-rich domain, a nuclearlocalization signal (NLS) domain, and two C-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 58865358 160 PTKVHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVERmhPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEIT 234
Cdd:cd12392   2 KNKLFVKGLPFSCTKEELEELFKQHGTVKDVRLVTYR--NGKPKGLAYVEYENEADASQAVLKTDGTEIKDHTIS 74

RNA recognition motif (RRM) found in RNA-binding protein RBM8A, RBM8B nd similar proteins; This subfamily corresponds to the RRM of RBM8, also termed binder of OVCA1-1 (BOV-1), or RNA-binding protein Y14, which is one of the components of the exon-exon junction complex (EJC). It has two isoforms, RBM8A and RBM8B, both of which are identical except that RBM8B is 16 amino acids shorter at its N-terminus. RBM8, together with other EJC components (such as Magoh, Aly/REF, RNPS1, Srm160, and Upf3), plays critical roles in postsplicing processing, including nuclear export and cytoplasmic localization of the mRNA, and the nonsense-mediated mRNA decay (NMD) surveillance process. RBM8 binds to mRNA 20-24 nucleotides upstream of a spliced exon-exon junction. It is also involved in spliced mRNA nuclear export, and the process of nonsense-mediated decay of mRNAs with premature stop codons. RBM8 forms a specific heterodimer complex with the EJC protein Magoh which then associates with Aly/REF, RNPS1, DEK, and SRm160 on the spliced mRNA, and inhibits ATP turnover by eIF4AIII, thereby trapping the EJC core onto RNA. RBM8 contains an N-terminal putative bipartite nuclear localization signal, one RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), in the central region, and a C-terminal serine-arginine rich region (SR domain) and glycine-arginine rich region (RG domain).

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 58865358 173 TKDHIMEIFSTYGKIKMIDMPVERMHPHLsKGYAYVEFENPDEAEKALKHMDGGQIDGQEITA 235
Cdd:cd12324  19 QEEDIHDKFAEFGEIKNLHLNLDRRTGFV-KGYALVEYETKKEAQAAIEGLNGKELLGQTISV 80

polyadenylate binding protein, human types 1, 2, 3, 4 family; These eukaryotic proteins recognize the poly-A of mRNA and consists of four tandem RNA recognition domains at the N-terminus (rrm: pfam00076) followed by a PABP-specific domain (pfam00658) at the C-terminus. The protein is involved in the transport of mRNA's from the nucleus to the cytoplasm. There are four paralogs in Homo sapiens which are expressed in testis, platelets, broadly expressed and of unknown tissue range.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 58865358   149 KERKRRSPSPKPTKVHIGRLTRNVTKDHIMEIFSTYGKIkmIDMPVERMHPHLSKGYAYVEFENPDEAEKALKHMDGGQI 228
Cdd:TIGR01628 167 KHEREAAPLKKFTNLYVKNLDPSVNEDKLRELFAKFGEI--TSAAVMKDGSGRSRGFAFVNFEKHEDAAKAVEEMNGKKI 244

                  ..
gi 58865358   229 DG 230
Cdd:TIGR01628 245 GL 246

RNA recognition motif 2 (RRM2) found in Nicotiana sylvestris chloroplastic 33 kDa ribonucleoprotein (NsCP33) and similar proteins; The family includes NsCP33, Arabidopsis thaliana chloroplastic 31 kDa ribonucleoprotein (CP31A) and mitochondrial glycine-rich RNA-binding protein 2 (AtGR-RBP2). NsCP33 may be involved in splicing and/or processing of chloroplast RNA's. AtCP31A, also called RNA-binding protein 1/2/3 (AtRBP33), or RNA-binding protein CP31A, or RNA-binding protein RNP-T, or RNA-binding protein cp31, is required for specific RNA editing events in chloroplasts and stabilizes specific chloroplast mRNAs, as well as for normal chloroplast development under cold stress conditions by stabilizing transcripts of numerous mRNAs under these conditions. CP31A may modulate telomere replication through RNA binding domains. AtGR-RBP2, also called AtRBG2, or glycine-rich protein 2 (AtGRP2), or mitochondrial RNA-binding protein 1a (At-mRBP1a), plays a role in RNA transcription or processing during stress. It binds RNAs and DNAs sequence with a preference to single-stranded nucleic acids. AtGR-RBP2 displays strong affinity to poly(U) sequence. It exerts cold and freezing tolerance, probably by exhibiting an RNA chaperone activity during the cold and freezing adaptation process. Some members in this family contain two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the second RRM motif.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 58865358 162 KVHIGRLTRNVTKDHIMEIFSTYGKI---KMI-DMPVERmhphlSKGYAYVEFENPDEAEKALKHMDGGQIDGQEIT 234
Cdd:cd21608   1 KLYVGNLSWDTTEDDLRDLFSEFGEVesaKVItDRETGR-----SRGFGFVTFSTAEAAEAAIDALNGKELDGRSIV 72

RNA recognition motif 1 (RRM1) found in heterogeneous nuclear ribonucleoprotein R (hnRNP R) and similar proteins; This subfamily corresponds to the RRM1 in hnRNP R, hnRNP Q, APOBEC-1 complementation factor (ACF), and dead end protein homolog 1 (DND1). hnRNP R is a ubiquitously expressed nuclear RNA-binding protein that specifically binds mRNAs with a preference for poly(U) stretches. It has been implicated in mRNA processing and mRNA transport, and also acts as a regulator to modify binding to ribosomes and RNA translation. hnRNP Q is also a ubiquitously expressed nuclear RNA-binding protein. It has been identified as a component of the spliceosome complex, as well as a component of the apobec-1 editosome, and has been implicated in the regulation of specific mRNA transport. ACF is an RNA-binding subunit of a core complex that interacts with apoB mRNA to facilitate C to U RNA editing. It may also act as an apoB mRNA recognition factor and chaperone, and play a key role in cell growth and differentiation. DND1 is essential for maintaining viable germ cells in vertebrates. It interacts with the 3'-untranslated region (3'-UTR) of multiple messenger RNAs (mRNAs) and prevents micro-RNA (miRNA) mediated repression of mRNA. This family also includes two functionally unknown RNA-binding proteins, RBM46 and RBM47. All members in this family, except for DND1, contain three conserved RNA recognition motifs (RRMs); DND1 harbors only two RRMs.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 58865358 161 TKVHIGRLTRNVTKDHIMEIFSTYGKIKMIDMpveRMHPH-LSKGYAYVEFENPDEAEKALKHMDGGQI 228
Cdd:cd12249   2 CEVFVGKIPRDVFEDELVPLFEKCGKIYELRL---MMDFSgLNRGYAFVTYTNKEAAQRAVKTLNNYEI 67

RNA recognition motif 1 (RRM1) found in plant pre-mRNA-splicing factor SF2 and similar proteins; This subgroup corresponds to the RRM1 of SF2, also termed SR1 protein, a plant serine/arginine (SR)-rich phosphoprotein similar to the mammalian splicing factor SF2/ASF. It promotes splice site switching in mammalian nuclear extracts. SF2 contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a C-terminal domain rich in proline, serine and lysine residues (PSK domain), a composition reminiscent of histones. This PSK domain harbors a putative phosphorylation site for the mitotic kinase cyclin/p34cdc2.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 58865358 162 KVHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVERMHPhlskGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12599   1 RVYVGNLPMDIREREVEDLFSKYGPVVSIDLKIPPRPP----AYAFVEFEDARDAEDAIRGRDGYDFDGHRL 68

RNA recognition motif (RRM) found in U1 small nuclear ribonucleoprotein 70 kDa (U1-70K) and similar proteins; This subfamily corresponds to the RRM of U1-70K, also termed snRNP70, a key component of the U1 snRNP complex, which is one of the key factors facilitating the splicing of pre-mRNA via interaction at the 5' splice site, and is involved in regulation of polyadenylation of some viral and cellular genes, enhancing or inhibiting efficient poly(A) site usage. U1-70K plays an essential role in targeting the U1 snRNP to the 5' splice site through protein-protein interactions with regulatory RNA-binding splicing factors, such as the RS protein ASF/SF2. Moreover, U1-70K protein can specifically bind to stem-loop I of the U1 small nuclear RNA (U1 snRNA) contained in the U1 snRNP complex. It also mediates the binding of U1C, another U1-specific protein, to the U1 snRNP complex. U1-70K contains a conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), followed by an adjacent glycine-rich region at the N-terminal half, and two serine/arginine-rich (SR) domains at the C-terminal half. The RRM is responsible for the binding of stem-loop I of U1 snRNA molecule. Additionally, the most prominent immunodominant region that can be recognized by auto-antibodies from autoimmune patients may be located within the RRM. The SR domains are involved in protein-protein interaction with SR proteins that mediate 5' splice site recognition. For instance, the first SR domain is necessary and sufficient for ASF/SF2 Binding. The family also includes Drosophila U1-70K that is an essential splicing factor required for viability in flies, but its SR domain is dispensable. The yeast U1-70k doesn't contain easily recognizable SR domains and shows low sequence similarity in the RRM region with other U1-70k proteins and therefore not included in this family. The RRM domain is dispensable for yeast U1-70K function.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 58865358 165 IGRLTRNVTKDHIMEIFSTYGKIKMIDMpVERMHPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12236   6 VARLSYDTTESKLRREFEKYGPIKRVRL-VRDKKTGKSRGYAFIEFEHERDMKAAYKHADGKKIDGRRV 73

RNA recognition motif 1 (RRM1) found in serine/arginine-rich splicing factor 1 (SRSF1) and similar proteins; This subgroup corresponds to the RRM1 in three serine/arginine (SR) proteins: serine/arginine-rich splicing factor 1 (SRSF1 or ASF-1), serine/arginine-rich splicing factor 9 (SRSF9 or SRp30C), and plant pre-mRNA-splicing factor SF2 (SR1). SRSF1 is a shuttling SR protein involved in constitutive and alternative splicing, nonsense-mediated mRNA decay (NMD), mRNA export and translation. It also functions as a splicing-factor oncoprotein that regulates apoptosis and proliferation to promote mammary epithelial cell transformation. SRSF9 has been implicated in the activity of many elements that control splice site selection, the alternative splicing of the glucocorticoid receptor beta in neutrophils and in the gonadotropin-releasing hormone pre-mRNA. It can also interact with other proteins implicated in alternative splicing, including YB-1, rSLM-1, rSLM-2, E4-ORF4, Nop30, and p32. Both, SRSF1 and SRSF9, contain two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal RS domains rich in serine-arginine dipeptides. In contrast, SF2 contains two N-terminal RRMs and a C-terminal PSK domain rich in proline, serine and lysine residues.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 58865358 162 KVHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVERMHPhlskGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12338   1 RIYVGNLPGDIRERDIEDLFYKYGPILAIDLKNRRRGP----PFAFVEFEDPRDAEDAIRGRDGYDFDGYRL 68

RNA recognition motif (RRM) found in eukaryotic translation initiation factor 3 subunit G (eIF-3G) and similar proteins; This subfamily corresponds to the RRM of eIF-3G and similar proteins. eIF-3G, also termed eIF-3 subunit 4, or eIF-3-delta, or eIF3-p42, or eIF3-p44, is the RNA-binding subunit of eIF3, a large multisubunit complex that plays a central role in the initiation of translation by binding to the 40 S ribosomal subunit and promoting the binding of methionyl-tRNAi and mRNA. eIF-3G binds 18 S rRNA and beta-globin mRNA, and therefore appears to be a nonspecific RNA-binding protein. eIF-3G is one of the cytosolic targets and interacts with mature apoptosis-inducing factor (AIF). eIF-3G contains one RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). This family also includes yeast eIF3-p33, a homolog of vertebrate eIF-3G, plays an important role in the initiation phase of protein synthesis in yeast. It binds both, mRNA and rRNA, fragments due to an RRM near its C-terminus.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*...
gi 58865358 168 LTRNVTKDHIMEIFSTYGKIKMIDMPVERmHPHLSKGYAYVEFENPDEAEKALKHMDG 225
Cdd:cd12408   7 LSEDATEEDLRELFRPFGPISRVYLAKDK-ETGQSKGFAFVTFETREDAERAIEKLNG 63

RNA recognition motif 2 (RRM2) found in vertebrate nucleolin; This subfamily corresponds to the RRM2 of ubiquitously expressed protein nucleolin, also termed protein C23, a multifunctional major nucleolar phosphoprotein that has been implicated in various metabolic processes, such as ribosome biogenesis, cytokinesis, nucleogenesis, cell proliferation and growth, cytoplasmic-nucleolar transport of ribosomal components, transcriptional repression, replication, signal transduction, inducing chromatin decondensation, etc. Nucleolin exhibits intrinsic self-cleaving, DNA helicase, RNA helicase and DNA-dependent ATPase activities. It can be phosphorylated by many protein kinases, such as the major mitotic kinase Cdc2, casein kinase 2 (CK2), and protein kinase C-zeta. Nucleolin shares similar domain architecture with gar2 from Schizosaccharomyces pombe and NSR1 from Saccharomyces cerevisiae. The highly phosphorylated N-terminal domain of nucleolin is made up of highly acidic regions separated from each other by basic sequences, and contains multiple phosphorylation sites. The central domain of nucleolin contains four closely adjacent N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), which suggests that nucleolin is potentially able to interact with multiple RNA targets. The C-terminal RGG (or GAR) domain of nucleolin is rich in glycine, arginine and phenylalanine residues, and contains high levels of NG,NG-dimethylarginines.RRM2, together with RRM1, binds specifically to RNA stem-loops containing the sequence (U/G)CCCG(A/G) in the loop.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 58865358 168 LTRNVTKDHIMEIFSTYGKIKMidmPVERMHPhlSKGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12404  11 LPYSTTQDELKEVFEDAVDIRI---PMGRDGR--SKGIAYIEFKSEAEAEKALEEKQGTEVDGRSI 71

RNA recognition motif (RRM) found in eukaryotic translation initiation factor 3 subunit B (eIF-3B) and similar proteins; This subfamily corresponds to the RRM domain in eukaryotic translation initiation factor 3 (eIF-3), a large multisubunit complex that plays a central role in the initiation of translation by binding to the 40 S ribosomal subunit and promoting the binding of methionyl-tRNAi and mRNA. eIF-3B, also termed eIF-3 subunit 9, or Prt1 homolog, eIF-3-eta, eIF-3 p110, or eIF-3 p116, is the major scaffolding subunit of eIF-3. It interacts with eIF-3 subunits A, G, I, and J. eIF-3B contains an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), which is involved in the interaction with eIF-3J. The interaction between eIF-3B and eIF-3J is crucial for the eIF-3 recruitment to the 40 S ribosomal subunit. eIF-3B also binds directly to domain III of the internal ribosome-entry site (IRES) element of hepatitis-C virus (HCV) RNA through its N-terminal RRM, which may play a critical role in both cap-dependent and cap-independent translation. Additional research has shown that eIF-3B may function as an oncogene in glioma cells and can be served as a potential therapeutic target for anti-glioma therapy. This family also includes the yeast homolog of eIF-3 subunit B (eIF-3B, also termed PRT1 or eIF-3 p90) that interacts with the yeast homologs of eIF-3 subunits A(TIF32), G(TIF35), I(TIF34), J(HCR1), and E(Pci8). In yeast, eIF-3B (PRT1) contains an N-terminal RRM that is directly involved in the interaction with eIF-3A (TIF32) and eIF-3J (HCR1). In contrast to its human homolog, yeast eIF-3B (PRT1) may have potential to bind its total RNA through its RRM domain.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 58865358 158 PKPTKVHIGRLTRNVTKdhimeIFSTYGKIKM--IDMPVERMHphLSKGYAYVEFENPDEAEKALKHMDGGQID 229
Cdd:cd12278  10 PVVGEEKLEKLKKVLTK-----IFSKFGSGKIvgIYMPVDETG--KTKGFAFVEYATPEEAKKAVKALNGYKLD 76

RNA recognition motif 2 (RRM2) found in (U)-binding-splicing factor PUF60 and similar proteins; This subfamily corresponds to the RRM2 of PUF60, also termed FUSE-binding protein-interacting repressor (FBP-interacting repressor or FIR), or Ro-binding protein 1 (RoBP1), or Siah-binding protein 1 (Siah-BP1). PUF60 is an essential splicing factor that functions as a poly-U RNA-binding protein required to reconstitute splicing in depleted nuclear extracts. Its function is enhanced through interaction with U2 auxiliary factor U2AF65. PUF60 also controls human c-myc gene expression by binding and inhibiting the transcription factor far upstream sequence element (FUSE)-binding-protein (FBP), an activator of c-myc promoters. PUF60 contains two central RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal U2AF (U2 auxiliary factor) homology motifs (UHM) that harbors another RRM and binds to tryptophan-containing linear peptide motifs (UHM ligand motifs, ULMs) in several nuclear proteins. Research indicates that PUF60 binds FUSE as a dimer, and only the first two RRM domains participate in the single-stranded DNA recognition.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 58865358 162 KVHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVERMhPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQ 231
Cdd:cd12371   2 RIYVASVHPDLSEDDIKSVFEAFGKIKSCSLAPDPE-TGKHKGYGFIEYENPQSAQDAIASMNLFDLGGQ 70

RNA recognition motif 1 (RRM1) found in granule-associated RNA binding proteins p40-TIA-1 and TIAR; This subfamily corresponds to the RRM1 of nucleolysin TIA-1 isoform p40 (p40-TIA-1 or TIA-1) and nucleolysin TIA-1-related protein (TIAR), both of which are granule-associated RNA binding proteins involved in inducing apoptosis in cytotoxic lymphocyte (CTL) target cells. TIA-1 and TIAR share high sequence similarity. They are expressed in a wide variety of cell types. TIA-1 can be phosphorylated by a serine/threonine kinase that is activated during Fas-mediated apoptosis.TIAR is mainly localized in the nucleus of hematopoietic and nonhematopoietic cells. It is translocated from the nucleus to the cytoplasm in response to exogenous triggers of apoptosis. Both, TIA-1 and TIAR, bind specifically to poly(A) but not to poly(C) homopolymers. They are composed of three N-terminal highly homologous RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a glutamine-rich C-terminal auxiliary domain containing a lysosome-targeting motif. TIA-1 and TIAR interact with RNAs containing short stretches of uridylates and their RRM2 can mediate the specific binding to uridylate-rich RNAs. The C-terminal auxiliary domain may be responsible for interacting with other proteins. In addition, TIA-1 and TIAR share a potential serine protease-cleavage site (Phe-Val-Arg) localized at the junction between their RNA binding domains and their C-terminal auxiliary domains.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 58865358 164 HIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVErmhPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12352   2 YVGNLDRQVTEDLILQLFSQIGPCKSCKMITE---HGGNDPYCFVEFYEHNHAAAALQAMNGRKILGKEV 68

RNA recognition motif (RRM) found in the Aly/REF family; This subfamily corresponds to the RRM of Aly/REF family which includes THO complex subunit 4 (THOC4, also termed Aly/REF), S6K1 Aly/REF-like target (SKAR, also termed PDIP3 or PDIP46) and similar proteins. THOC4 is an mRNA transporter protein with a well conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). It is involved in RNA transportation from the nucleus, and was initially identified as a transcription coactivator of LEF-1 and AML-1 for the TCRalpha enhancer function. In addition, THOC4 specifically binds to rhesus (RH) promoter in erythroid, and might be a novel transcription cofactor for erythroid-specific genes. SKAR shows high sequence homology with THOC4 and possesses one RRM as well. SKAR is widely expressed and localizes to the nucleus. It may be a critical player in the function of S6K1 in cell and organism growth control by binding the activated, hyperphosphorylated form of S6K1 but not S6K2. Furthermore, SKAR functions as a protein partner of the p50 subunit of DNA polymerase delta. In addition, SKAR may have particular importance in pancreatic beta cell size determination and insulin secretion.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 58865358 161 TKVHIGRLTRNVTKDHIMEIFSTYGKIKMidmpVERMHPHL--SKGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12418   1 TRVRVSNLHPDVTEEDLRELFGRVGPVKS----VKINYDRSgrSTGTAYVVFERPEDAEKAIKQFDGVLLDGQPM 71

RNA recognition motif 6 (RRM6) found in RNA-binding protein 19 (RBM19 or RBD-1) and RNA recognition motif 5 (RRM5) found in multiple RNA-binding domain-containing protein 1 (MRD1); This subfamily corresponds to the RRM6 of RBM19 and RRM5 of MRD1. RBM19, also termed RNA-binding domain-1 (RBD-1), is a nucleolar protein conserved in eukaryotes. It is involved in ribosome biogenesis by processing rRNA and is essential for preimplantation development. It has a unique domain organization containing 6 conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). MRD1 is encoded by a novel yeast gene MRD1 (multiple RNA-binding domain). It is well-conserved in yeast and its homologs exist in all eukaryotes. MRD1 is present in the nucleolus and the nucleoplasm. It interacts with the 35 S precursor rRNA (pre-rRNA) and U3 small nucleolar RNAs (snoRNAs). It is essential for the initial processing at the A0-A2 cleavage sites in the 35 S pre-rRNA. MRD1 contains 5 conserved RRMs, which may play an important structural role in organizing specific rRNA processing events.

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                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 58865358 161 TKVHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVERMHPHlsKGYAYVEFENPDEAEKALKHM 223
Cdd:cd12320   1 TKLIVKNVPFEATRKEIRELFSPFGQLKSVRLPKKFDGSH--RGFAFVEFVTKQEAQNAMEAL 61

RNA recognition motif 3 (RRM3) found in CELF/Bruno-like family of RNA binding proteins CELF1, CELF2, CELF3, CELF4, CELF5, CELF6 and similar proteins; This subgroup corresponds to the RRM3 of the CUGBP1 and ETR-3-like factors (CELF) or BRUNOL (Bruno-like) proteins, a family of structurally related RNA-binding proteins involved in the regulation of pre-mRNA splicing in the nucleus and in the control of mRNA translation and deadenylation in the cytoplasm. The family contains six members: CELF-1 (also termed BRUNOL-2, or CUG-BP1, or NAPOR, or EDEN-BP), CELF-2 (also termed BRUNOL-3, or ETR-3, or CUG-BP2, or NAPOR-2), CELF-3 (also termed BRUNOL-1, or TNRC4, or ETR-1, or CAGH4, or ER DA4), CELF-4 (also termed BRUNOL-4), CELF-5 (also termed BRUNOL-5), CELF-6 (also termed BRUNOL-6). They all contain three highly conserved RNA recognition motifs (RRMs), also known as RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains): two consecutive RRMs (RRM1 and RRM2) situated in the N-terminal region followed by a linker region and the third RRM (RRM3) close to the C-terminus of the protein. The low sequence conservation of the linker region is highly suggestive of a large variety in the co-factors that associate with the various CELF family members. Based on both sequence similarity and function, the CELF family can be divided into two subfamilies, the first containing CELFs 1 and 2, and the second containing CELFs 3, 4, 5, and 6. The different CELF proteins may act through different sites on at least some substrates. Furthermore, CELF proteins may interact with each other in varying combinations to influence alternative splicing in different contexts.

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                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 58865358 178 MEIFSTYGKIK----MIDMpvermHPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEIT 234
Cdd:cd12362  16 YQLFAPFGNVVsakvFVDK-----NTGRSKGFGFVSYDNPLSAQAAIKAMNGFQVGGKRLK 71

RNA recognition motif 2 (RRM2) found in U2 large nuclear ribonucleoprotein auxiliary factor U2AF 65 kDa subunit (U2AF65) and similar proteins; This subfamily corresponds to the RRM2 of U2AF65 and dU2AF50. U2AF65, also termed U2AF2, is the large subunit of U2 small nuclear ribonucleoprotein (snRNP) auxiliary factor (U2AF), which has been implicated in the recruitment of U2 snRNP to pre-mRNAs and is a highly conserved heterodimer composed of large and small subunits. U2AF65 specifically recognizes the intron polypyrimidine tract upstream of the 3' splice site and promotes binding of U2 snRNP to the pre-mRNA branchpoint. U2AF65 also plays an important role in the nuclear export of mRNA. It facilitates the formation of a messenger ribonucleoprotein export complex, containing both the NXF1 receptor and the RNA substrate. Moreover, U2AF65 interacts directly and specifically with expanded CAG RNA, and serves as an adaptor to link expanded CAG RNA to NXF1 for RNA export. U2AF65 contains an N-terminal RS domain rich in arginine and serine, followed by a proline-rich segment and three C-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The N-terminal RS domain stabilizes the interaction of U2 snRNP with the branch point (BP) by contacting the branch region, and further promotes base pair interactions between U2 snRNA and the BP. The proline-rich segment mediates protein-protein interactions with the RRM domain of the small U2AF subunit (U2AF35 or U2AF1). The RRM1 and RRM2 are sufficient for specific RNA binding, while RRM3 is responsible for protein-protein interactions. The family also includes Splicing factor U2AF 50 kDa subunit (dU2AF50), the Drosophila ortholog of U2AF65. dU2AF50 functions as an essential pre-mRNA splicing factor in flies. It associates with intronless mRNAs and plays a significant and unexpected role in the nuclear export of a large number of intronless mRNAs.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 58865358 162 KVHIGRLTRNVTKDHIMEIFSTYGKIKMIDMpVERMHPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEIT 234
Cdd:cd12231   2 KLFIGGLPNYLNEDQVKELLQSFGKLKAFNL-VKDSATGLSKGYAFCEYVDDNVTDQAIAGLNGMQLGDKKLL 73

RNA recognition motif 3 (RRM3) found found in type I polyadenylate-binding proteins; This subfamily corresponds to the RRM3 of type I poly(A)-binding proteins (PABPs), highly conserved proteins that bind to the poly(A) tail present at the 3' ends of most eukaryotic mRNAs. They have been implicated in the regulation of poly(A) tail length during the polyadenylation reaction, translation initiation, mRNA stabilization by influencing the rate of deadenylation and inhibition of mRNA decapping. The family represents type I polyadenylate-binding proteins (PABPs), including polyadenylate-binding protein 1 (PABP-1 or PABPC1), polyadenylate-binding protein 3 (PABP-3 or PABPC3), polyadenylate-binding protein 4 (PABP-4 or APP-1 or iPABP), polyadenylate-binding protein 5 (PABP-5 or PABPC5), polyadenylate-binding protein 1-like (PABP-1-like or PABPC1L), polyadenylate-binding protein 1-like 2 (PABPC1L2 or RBM32), polyadenylate-binding protein 4-like (PABP-4-like or PABPC4L), yeast polyadenylate-binding protein, cytoplasmic and nuclear (PABP or ACBP-67), and similar proteins. PABP-1 is an ubiquitously expressed multifunctional protein that may play a role in 3' end formation of mRNA, translation initiation, mRNA stabilization, protection of poly(A) from nuclease activity, mRNA deadenylation, inhibition of mRNA decapping, and mRNP maturation. Although PABP-1 is thought to be a cytoplasmic protein, it is also found in the nucleus. PABP-1 may be involved in nucleocytoplasmic trafficking and utilization of mRNP particles. PABP-1 contains four copies of RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), a less well conserved linker region, and a proline-rich C-terminal conserved domain (CTD). PABP-3 is a testis-specific poly(A)-binding protein specifically expressed in round spermatids. It is mainly found in mammalian and may play an important role in the testis-specific regulation of mRNA homeostasis. PABP-3 shows significant sequence similarity to PABP-1. However, it binds to poly(A) with a lower affinity than PABP-1. PABP-1 possesses an A-rich sequence in its 5'-UTR and allows binding of PABP and blockage of translation of its own mRNA. In contrast, PABP-3 lacks the A-rich sequence in its 5'-UTR. PABP-4 is an inducible poly(A)-binding protein (iPABP) that is primarily localized to the cytoplasm. It shows significant sequence similarity to PABP-1 as well. The RNA binding properties of PABP-1 and PABP-4 appear to be identical. PABP-5 is encoded by PABPC5 gene within the X-specific subinterval, and expressed in fetal brain and in a range of adult tissues in mammalian, such as ovary and testis. It may play an important role in germ cell development. Moreover, unlike other PABPs, PABP-5 contains only four RRMs, but lacks both the linker region and the CTD. PABP-1-like and PABP-1-like 2 are the orthologs of PABP-1. PABP-4-like is the ortholog of PABP-5. Their cellular functions remain unclear. The family also includes the yeast PABP, a conserved poly(A) binding protein containing poly(A) tails that can be attached to the 3'-ends of mRNAs. The yeast PABP and its homologs may play important roles in the initiation of translation and in mRNA decay. Like vertebrate PABP-1, the yeast PABP contains four RRMs, a linker region, and a proline-rich CTD as well. The first two RRMs are mainly responsible for specific binding to poly(A). The proline-rich region may be involved in protein-protein interactions.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 58865358 161 TKVHIGRLTRNVTKDHIMEIFSTYGKIKMIDmpVERMHPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12380   2 TNVYVKNFGEDVDDDELKELFEKYGKITSAK--VMKDDSGKSKGFGFVNFENHEAAQKAVEELNGKELNGKKL 72

RNA recognition motif 1 (RRM1) found in splicing factor 3B subunit 4 (SF3B4) and similar proteins; This subfamily corresponds to the RRM1 of SF3B4, also termed pre-mRNA-splicing factor SF3b 49 kDa (SF3b50), or spliceosome-associated protein 49 (SAP 49). SF3B4 a component of the multiprotein complex splicing factor 3b (SF3B), an integral part of the U2 small nuclear ribonucleoprotein (snRNP) and the U11/U12 di-snRNP. SF3B is essential for the accurate excision of introns from pre-messenger RNA, and is involved in the recognition of the pre-mRNA's branch site within the major and minor spliceosomes. SF3B4 functions to tether U2 snRNP with pre-mRNA at the branch site during spliceosome assembly. It is an evolutionarily highly conserved protein with orthologs across diverse species. SF3B4 contains two closely adjacent N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). It binds directly to pre-mRNA and also interacts directly and highly specifically with another SF3B subunit called SAP 145.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 58865358 163 VHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVER---MHphlsKGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12334   1 VYVGNLDEKVTEELLWELFIQAGPVVNVHMPKDRvtqQH----QGYGFVEFLSEEDADYAIKIMNMIKLYGKPI 70

RNA recognition motif 1 (RRM1) found in yeast nuclear and cytoplasmic polyadenylated RNA-binding protein PUB1 and similar proteins; This subgroup corresponds to the RRM1 of yeast protein PUB1, also termed ARS consensus-binding protein ACBP-60, or poly uridylate-binding protein, or poly(U)-binding protein. PUB1 has been identified as both, a heterogeneous nuclear RNA-binding protein (hnRNP) and a cytoplasmic mRNA-binding protein (mRNP), which may be stably bound to a translationally inactive subpopulation of mRNAs within the cytoplasm. It is distributed in both, the nucleus and the cytoplasm, and binds to poly(A)+ RNA (mRNA or pre-mRNA). Although it is one of the major cellular proteins cross-linked by UV light to polyadenylated RNAs in vivo, PUB1 is nonessential for cell growth in yeast. PUB1 also binds to T-rich single stranded DNA (ssDNA); however, there is no strong evidence implicating PUB1 in the mechanism of DNA replication. PUB1 contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a GAR motif (glycine and arginine rich stretch) that is located between RRM2 and RRM3.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 58865358 163 VHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVERMHPHLSkgYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12614   1 LYVGNLDPRVTEDLLQEIFAVTGPVENCKIIPDKNSKGVN--YGFVEYYDRRSAEIAIQTLNGRQIFGQEI 69

RNA recognition motif (RRM) found in serine/arginine-rich splicing factor SRSF10, SRSF12 and similar proteins; This subfamily corresponds to the RRM of SRSF10 and SRSF12. SRSF10, also termed 40 kDa SR-repressor protein (SRrp40), or FUS-interacting serine-arginine-rich protein 1 (FUSIP1), or splicing factor SRp38, or splicing factor, arginine/serine-rich 13A (SFRS13A), or TLS-associated protein with Ser-Arg repeats (TASR). It is a serine-arginine (SR) protein that acts as a potent and general splicing repressor when dephosphorylated. It mediates global inhibition of splicing both in M phase of the cell cycle and in response to heat shock. SRSF10 emerges as a modulator of cholesterol homeostasis through the regulation of low-density lipoprotein receptor (LDLR) splicing efficiency. It also regulates cardiac-specific alternative splicing of triadin pre-mRNA and is required for proper Ca2+ handling during embryonic heart development. In contrast, the phosphorylated SRSF10 functions as a sequence-specific splicing activator in the presence of a nuclear cofactor. It activates distal alternative 5' splice site of adenovirus E1A pre-mRNA in vivo. Moreover, SRSF10 strengthens pre-mRNA recognition by U1 and U2 snRNPs. SRSF10 localizes to the nuclear speckles and can shuttle between nucleus and cytoplasm. SRSF12, also termed 35 kDa SR repressor protein (SRrp35), or splicing factor, arginine/serine-rich 13B (SFRS13B), or splicing factor, arginine/serine-rich 19 (SFRS19), is a serine/arginine (SR) protein-like alternative splicing regulator that antagonizes authentic SR proteins in the modulation of alternative 5' splice site choice. For instance, it activates distal alternative 5' splice site of the adenovirus E1A pre-mRNA in vivo. Both, SRSF10 and SRSF12, contain a single N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), followed by a C-terminal RS domain rich in serine-arginine dipeptides.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 58865358 161 TKVHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVErMHPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12312   1 TSLFVRNVADDTRPDDLRREFGRYGPIVDVYIPLD-FYTRRPRGFAYIQFEDVRDAEDALYYLDRTRFLGREI 72

RNA recognition motif 1 (RRM1) and 2 (RRM2) found in RRM-containing coactivator activator/modulator (CoAA) and similar proteins; This subfamily corresponds to the RRM in CoAA (also known as RBM14 or PSP2) and RNA-binding protein 4 (RBM4). CoAA is a heterogeneous nuclear ribonucleoprotein (hnRNP)-like protein identified as a nuclear receptor coactivator. It mediates transcriptional coactivation and RNA splicing effects in a promoter-preferential manner, and is enhanced by thyroid hormone receptor-binding protein (TRBP). CoAA contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a TRBP-interacting domain. RBM4 is a ubiquitously expressed splicing factor with two isoforms, RBM4A (also known as Lark homolog) and RBM4B (also known as RBM30), which are very similar in structure and sequence. RBM4 may also function as a translational regulator of stress-associated mRNAs as well as play a role in micro-RNA-mediated gene regulation. RBM4 contains two N-terminal RRMs, a CCHC-type zinc finger, and three alanine-rich regions within their C-terminal regions. This family also includes Drosophila RNA-binding protein lark (Dlark), a homolog of human RBM4. It plays an important role in embryonic development and in the circadian regulation of adult eclosion. Dlark shares high sequence similarity with RBM4 at the N-terminal region. However, Dlark has three proline-rich segments instead of three alanine-rich segments within the C-terminal region.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 58865358 162 KVHIGRLTRNVTKDHIMEIFSTYGKIKMIDmpvermhphLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEIT 234
Cdd:cd12343   1 KIFVGNLPDAATSEELRALFEKYGKVTECD---------IVKNYAFVHMEKEEDAEDAIKALNGYEFMGSRIN 64

RNA recognition motif 5 (RRM5) found in RNA-binding protein 19 (RBM19 or RBD-1) and similar proteins; This subfamily corresponds to the RRM5 of RBM19 and RRM4 of MRD1. RBM19, also termed RNA-binding domain-1 (RBD-1), is a nucleolar protein conserved in eukaryotes involved in ribosome biogenesis by processing rRNA and is essential for preimplantation development. It has a unique domain organization containing 6 conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

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                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 58865358 173 TKDHIMEIFSTYGKIKMIDMPVER--MHPHLSKGYAYVEFENPDEAEKALKHMDGGQIDG 230
Cdd:cd12318  13 TEEALKKHFEKCGPIRSVTIAKKKdpKGPLLSMGYGFVEFKSPEAAQKALKQLQGTVLDG 72

poly-U binding splicing factor, half-pint family; The proteins represented by this model contain three RNA recognition motifs (rrm: pfam00076) and have been characterized as poly-pyrimidine tract binding proteins associated with RNA splicing factors. In the case of PUF60 (GP|6176532), in complex with p54, and in the presence of U2AF, facilitates association of U2 snRNP with pre-mRNA.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 58865358   162 KVHIGRLTRNVTKDHIMEIFSTYGKIKMIDM---PVERMHphlsKGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:TIGR01645 109 RVYVGSISFELREDTIRRAFDPFGPIKSINMswdPATGKH----KGFAFVEYEVPEAAQLALEQMNGQMLGGRNI 179

RNA recognition motif 3 (RRM3) found in yeast negative growth regulatory protein NGR1 (RBP1), yeast protein NAM8 and similar proteins; This subfamily corresponds to the RRM3 of NGR1 and NAM8. NGR1, also termed RNA-binding protein RBP1, is a putative glucose-repressible protein that binds both RNA and single-stranded DNA (ssDNA) in yeast. It may function in regulating cell growth in early log phase, possibly through its participation in RNA metabolism. NGR1 contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a glutamine-rich stretch that may be involved in transcriptional activity. In addition, NGR1 has an asparagine-rich region near the carboxyl terminus which also harbors a methionine-rich region. The family also includes protein NAM8, which is a putative RNA-binding protein that acts as a suppressor of mitochondrial splicing deficiencies when overexpressed in yeast. It may be a non-essential component of the mitochondrial splicing machinery. Like NGR1, NAM8 contains two RRMs.

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gi 58865358 161 TKVHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVermhphlSKGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12346   2 TTVFVGGLDPNVTEEDLRVLFGPFGEIVYVKIPP-------GKGCGFVQFVNRASAEAAIQKLQGTPIGGSRI 67

RNA recognition motif (RRM) found in AZoospermia (DAZ) autosomal homologs, DAZL (DAZ-like) and BOULE; This subfamily corresponds to the RRM domain of two Deleted in AZoospermia (DAZ) autosomal homologs, DAZL (DAZ-like) and BOULE. BOULE is the founder member of the family and DAZL arose from BOULE in an ancestor of vertebrates. The DAZ gene subsequently originated from a duplication transposition of the DAZL gene. Invertebrates contain a single DAZ homolog, BOULE, while vertebrates, other than catarrhine primates, possess both BOULE and DAZL genes. The catarrhine primates possess BOULE, DAZL, and DAZ genes. The family members encode closely related RNA-binding proteins that are required for fertility in numerous organisms. These proteins contain an RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a varying number of copies of a DAZ motif, believed to mediate protein-protein interactions. DAZL and BOULE contain a single copy of the DAZ motif, while DAZ proteins can contain 8-24 copies of this repeat. Although their specific biochemical functions remain to be investigated, DAZL proteins may interact with poly(A)-binding proteins (PABPs), and act as translational activators of specific mRNAs during gametogenesis.

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gi 58865358 160 PTKVHIGRLTRNVTKDHIMEIFSTYGKIKmiDMPVERMHPHLSKGYAYVEFENPDEAEKALK 221
Cdd:cd12412   2 PNRIFVGGIDWDTTEEELREFFSKFGKVK--DVKIIKDRAGVSKGYGFVTFETQEDAEKIQK 61

RNA recognition motif 1 (RRM1) found in yeast nucleolar protein 3 (Npl3p) and similar proteins; This subfamily corresponds to the RRM1 of Npl3p, also termed mitochondrial targeting suppressor 1 protein, or nuclear polyadenylated RNA-binding protein 1. Npl3p is a major yeast RNA-binding protein that competes with 3'-end processing factors, such as Rna15, for binding to the nascent RNA, protecting the transcript from premature termination and coordinating transcription termination and the packaging of the fully processed transcript for export. It specifically recognizes a class of G/U-rich RNAs. Npl3p is a multi-domain protein containing two central RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), separated by a short linker and a C-terminal domain rich in glycine, arginine and serine residues.

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gi 58865358 162 KVHIGRLTRNVTKDHIMEIFSTYGKIKMIDMPVERmhphlskGYAYVEFENPDEAEKALKHMDGGQIDGQEITAT 236
Cdd:cd12340   1 RLFVRPFPPDTSESAIREIFSPYGPVKEVKMLSDS-------NFAFVEFEELEDAIRAKDSVHGRVLNNEPLYVT 68

RNA recognition motif (RRM) found in yeast nuclear polyadenylated RNA-binding protein 3 (Nab3p) and similar proteins; This subfamily corresponds to the RRM of Nab3p, an acidic nuclear polyadenylated RNA-binding protein encoded by Saccharomyces cerevisiae NAB3 gene that is essential for cell viability. Nab3p is predominantly localized within the nucleoplasm and essential for growth in yeast. It may play an important role in packaging pre-mRNAs into ribonucleoprotein structures amenable to efficient nuclear RNA processing. Nab3p contains an N-terminal aspartic/glutamic acid-rich region, a central RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal region rich in glutamine and proline residues.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 58865358 165 IGRL-TRNVTKDHIMEIFSTYGKIKMIDmpvermhphLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEI 233
Cdd:cd12342   4 IGNLpTKRVSKEDLFRIFSPYGHLMQIV---------IKNAFGFVQFDSPQSCRNAIECEQGEMNRGKKL 64

RNA recognition motif 1 (RRM1) and 2 (RRM2) found in RNA-binding protein 5 (RBM5) and similar proteins; This subfamily includes the RRM1 and RRM2 of RNA-binding protein 5 (RBM5 or LUCA15 or H37) and RNA-binding protein 10 (RBM10 or S1-1), and the RRM2 of RNA-binding protein 6 (RBM6 or NY-LU-12 or g16 or DEF-3). These RBMs share high sequence homology and may play an important role in regulating apoptosis. RBM5 is a known modulator of apoptosis. It may also act as a tumor suppressor or an RNA splicing factor. RBM6 has been predicted to be a nuclear factor based on its nuclear localization signal. Both, RBM6 and RBM5, specifically bind poly(G) RNA. RBM10 is a paralog of RBM5. It may play an important role in mRNA generation, processing and degradation in several cell types. The rat homolog of human RBM10 is protein S1-1, a hypothetical RNA binding protein with poly(G) and poly(U) binding capabilities. All family members contain two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), two C2H2-type zinc fingers, and a G-patch/D111 domain.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 58865358 160 PTKVHIGR-LTRNVTKDHIMEIFSTYGKIKMIDMPVER-MHPHLSKGYAYVEFENPDEAEKALKHMDGG----QIDGQEI 233
Cdd:cd12313   1 PTNVLILRgLDVLTTEEDILSALQAHADLPIKDVRLIRdKLTGTSRGFAFVEFSSLEDATQVMDALQNLlppfKIDGRVV 80

                .
gi 58865358 234 T 234
Cdd:cd12313  81 S 81

RNA recognition motif 3 (RRM3) found in U2 large nuclear ribonucleoprotein auxiliary factor U2AF 65 kDa subunit (U2AF65) and similar proteins; This subfamily corresponds to the RRM3 of U2AF65 and dU2AF50. U2AF65, also termed U2AF2, is the large subunit of U2 small nuclear ribonucleoprotein (snRNP) auxiliary factor (U2AF), which has been implicated in the recruitment of U2 snRNP to pre-mRNAs and is a highly conserved heterodimer composed of large and small subunits. U2AF65 specifically recognizes the intron polypyrimidine tract upstream of the 3' splice site and promotes binding of U2 snRNP to the pre-mRNA branchpoint. U2AF65 also plays an important role in the nuclear export of mRNA. It facilitates the formation of a messenger ribonucleoprotein export complex, containing both the NXF1 receptor and the RNA substrate. Moreover, U2AF65 interacts directly and specifically with expanded CAG RNA, and serves as an adaptor to link expanded CAG RNA to NXF1 for RNA export. U2AF65 contains an N-terminal RS domain rich in arginine and serine, followed by a proline-rich segment and three C-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The N-terminal RS domain stabilizes the interaction of U2 snRNP with the branch point (BP) by contacting the branch region, and further promotes base pair interactions between U2 snRNA and the BP. The proline-rich segment mediates protein-protein interactions with the RRM domain of the small U2AF subunit (U2AF35 or U2AF1). The RRM1 and RRM2 are sufficient for specific RNA binding, while RRM3 is responsible for protein-protein interactions. The family also includes Splicing factor U2AF 50 kDa subunit (dU2AF50), the Drosophila ortholog of U2AF65. dU2AF50 functions as an essential pre-mRNA splicing factor in flies. It associates with intronless mRNAs and plays a significant and unexpected role in the nuclear export of a large number of intronless mRNAs.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 58865358 174 KDHIMEIFSTYGKIK--MIDMPVERMHPHLSKGYAYVEFENPDEAEKALKHMDGGQIDGQEITAT 236
Cdd:cd12232  25 LEDVKEECSKYGKVLsvVIPRPEAEGVDVPGVGKVFVEFEDVEDAQKAQKALAGRKFDGRTVVAS 89