RNA recognition motif (RRM) superfamily; RRM, also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), is a highly abundant domain in eukaryotes found in proteins involved in post-transcriptional gene expression processes including mRNA and rRNA processing, RNA export, and RNA stability. This domain is 90 amino acids in length and consists of a four-stranded beta-sheet packed against two alpha-helices. RRM usually interacts with ssRNA, but is also known to interact with ssDNA as well as proteins. RRM binds a variable number of nucleotides, ranging from two to eight. The active site includes three aromatic side-chains located within the conserved RNP1 and RNP2 motifs of the domain. The RRM domain is found in a variety heterogeneous nuclear ribonucleoproteins (hnRNPs), proteins implicated in regulation of alternative splicing, and protein components of small nuclear ribonucleoproteins (snRNPs).

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMKYGFAFVDFEDSRDAEDACHDLDGKTMEGSsmRLVVEMARG 74
Cdd:cd12337   1 RVYIGRLPYRARERDVERFFRGYGRIRDINLKNGFGFVEFEDPRDADDAVYELNGKELCGE--RVIVEHARG 70

RNA recognition motif 1 (RRM1) found in serine/arginine-rich splicing factor 4 (SRSF4) and similar proteins; This subfamily corresponds to the RRM1 in three serine/arginine (SR) proteins: serine/arginine-rich splicing factor 4 (SRSF4 or SRp75 or SFRS4), serine/arginine-rich splicing factor 5 (SRSF5 or SRp40 or SFRS5 or HRS), serine/arginine-rich splicing factor 6 (SRSF6 or SRp55). SRSF4 plays an important role in both, constitutive and alternative, splicing of many pre-mRNAs. It can shuttle between the nucleus and cytoplasm. SRSF5 regulates both alternative splicing and basal splicing. It is the only SR protein efficiently selected from nuclear extracts (NE) by the splicing enhancer (ESE) and essential for enhancer activation. SRSF6 preferentially interacts with a number of purine-rich splicing enhancers (ESEs) to activate splicing of the ESE-containing exon. It is the only protein from HeLa nuclear extract or purified SR proteins that specifically binds B element RNA after UV irradiation. SRSF6 may also recognize different types of RNA sites. Members in this family contain two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a C-terminal RS domains rich in serine-arginine dipeptides.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMKYGFAFVDFEDSRDAEDACHDLDGKTMEGSsmRLVVEMARG 74
Cdd:cd12337   1 RVYIGRLPYRARERDVERFFRGYGRIRDINLKNGFGFVEFEDPRDADDAVYELNGKELCGE--RVIVEHARG 70

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 71996524     4 LYLGKIPYNARERDVERFLKGYGKINNISMKY-------GFAFVDFEDSRDAEDACHDLDGKTMEGSSMR 66
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGPIKSIRLVRdetgrskGFAFVEFEDEEDAEKAIEALNGKELGGRELK 70

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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 71996524     1 MPRLYLGKIPYNARERDVERFLKGYGKINNISMKY--------GFAFVDFEDSRDAEDACHDLDGKTMEGSSMRL 67
Cdd:TIGR01645 107 MCRVYVGSISFELREDTIRRAFDPFGPIKSINMSWdpatgkhkGFAFVEYEVPEAAQLALEQMNGQMLGGRNIKV 181

RNA recognition motif 1 (RRM1) found in serine/arginine-rich splicing factor 4 (SRSF4) and similar proteins; This subfamily corresponds to the RRM1 in three serine/arginine (SR) proteins: serine/arginine-rich splicing factor 4 (SRSF4 or SRp75 or SFRS4), serine/arginine-rich splicing factor 5 (SRSF5 or SRp40 or SFRS5 or HRS), serine/arginine-rich splicing factor 6 (SRSF6 or SRp55). SRSF4 plays an important role in both, constitutive and alternative, splicing of many pre-mRNAs. It can shuttle between the nucleus and cytoplasm. SRSF5 regulates both alternative splicing and basal splicing. It is the only SR protein efficiently selected from nuclear extracts (NE) by the splicing enhancer (ESE) and essential for enhancer activation. SRSF6 preferentially interacts with a number of purine-rich splicing enhancers (ESEs) to activate splicing of the ESE-containing exon. It is the only protein from HeLa nuclear extract or purified SR proteins that specifically binds B element RNA after UV irradiation. SRSF6 may also recognize different types of RNA sites. Members in this family contain two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a C-terminal RS domains rich in serine-arginine dipeptides.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMKYGFAFVDFEDSRDAEDACHDLDGKTMEGSsmRLVVEMARG 74
Cdd:cd12337   1 RVYIGRLPYRARERDVERFFRGYGRIRDINLKNGFGFVEFEDPRDADDAVYELNGKELCGE--RVIVEHARG 70

RNA recognition motif 1 (RRM1) found in vertebrate serine/arginine-rich splicing factor 5 (SRSF5); This subgroup corresponds to the RRM1 of SRSF5, also termed delayed-early protein HRS, or pre-mRNA-splicing factor SRp40, or splicing factor, arginine/serine-rich 5 (SFRS5). SFSF5 is an essential splicing regulatory serine/arginine (SR) protein that regulates both alternative splicing and basal splicing. It is the only SR protein efficiently selected from nuclear extracts (NE) by the splicing enhancer (ESE) and it is necessary for enhancer activation. SRSF5 also functions as a factor required for insulin-regulated splice site selection for protein kinase C (PKC) betaII mRNA. It is involved in the regulation of PKCbetaII exon inclusion by insulin via its increased phosphorylation by a phosphatidylinositol 3-kinase (PI 3-kinase) signaling pathway. Moreover, SRSF5 can regulate alternative splicing in exon 9 of glucocorticoid receptor pre-mRNA in a dose-dependent manner. SRSF5 contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a C-terminal RS domains rich in serine-arginine dipeptides. The specific RNA binding by SRSF5 requires the phosphorylation of its SR domain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMKYGFAFVDFEDSRDAEDACHDLDGKtmEGSSMRLVVEMAR 73
Cdd:cd12595   1 RVFIGRLNPAAREKDVERFFKGYGRIRDIDLKRGFGFVEFEDPRDADDAVYELDGK--ELCNERVTIEHAR 69

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 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMKY---GFAFVDFEDSRDAEDACHDLDGKTMEGSsmRLVVEMARG 74
Cdd:cd12373   1 KVYVGNLGPRVTKRELEDAFEKYGPLRNVWVARnppGFAFVEFEDPRDAEDAVRALDGRRICGS--RVRVELSRG 73

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 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMKY-----GFAFVDFEDSRDAEDACHDLDGKTMEGSSMRL 67
Cdd:cd12599   1 RVYVGNLPMDIREREVEDLFSKYGPVVSIDLKIpprppAYAFVEFEDARDAEDAIRGRDGYDFDGHRLRV 70

RNA recognition motif (RRM) superfamily; RRM, also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), is a highly abundant domain in eukaryotes found in proteins involved in post-transcriptional gene expression processes including mRNA and rRNA processing, RNA export, and RNA stability. This domain is 90 amino acids in length and consists of a four-stranded beta-sheet packed against two alpha-helices. RRM usually interacts with ssRNA, but is also known to interact with ssDNA as well as proteins. RRM binds a variable number of nucleotides, ranging from two to eight. The active site includes three aromatic side-chains located within the conserved RNP1 and RNP2 motifs of the domain. The RRM domain is found in a variety heterogeneous nuclear ribonucleoproteins (hnRNPs), proteins implicated in regulation of alternative splicing, and protein components of small nuclear ribonucleoproteins (snRNPs).

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 71996524   4 LYLGKIPYNARERDVERFLKGYGKINNISMKY-------GFAFVDFEDSRDAEDACHDLDGKTMEGSSMRL 67
Cdd:cd00590   1 LFVGNLPPDTTEEDLRELFSKFGEVVSVRIVRdrdgkskGFAFVEFESPEDAEKALEALNGTELGGRPLKV 71

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 71996524     4 LYLGKIPYNARERDVERFLKGYGKINNISMKY-------GFAFVDFEDSRDAEDACHDLDGKTMEGSSMR 66
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGPIKSIRLVRdetgrskGFAFVEFEDEEDAEKAIEALNGKELGGRELK 70

RNA recognition motif (RRM) domain [Translation, ribosomal structure and biogenesis];

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71996524   1 MPRLYLGKIPYNARERDVERFLKGYGKINNISMKY--------GFAFVDFEDSRDAEDACHDLDGKTMEGSSmrLVVEMA 72
Cdd:COG0724   1 SMKIYVGNLPYSVTEEDLRELFSEYGEVTSVKLITdretgrsrGFGFVEMPDDEEAQAAIEALNGAELMGRT--LKVNEA 78

                ....*..
gi 71996524  73 RGKPRGN 79
Cdd:COG0724  79 RPREERP 85

RNA recognition motif 2 (RRM2) found in yeast multiple RNA-binding domain-containing protein 1 (MRD1) and similar proteins; This subgroup corresponds to the RRM2 of MRD1 which 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 RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), which may play an important structural role in organizing specific rRNA processing events.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMKY--------GFAFVDFEDSRDAEDACHDLDGKTMEGSSM 65
Cdd:cd12566   4 RLFLRNLPYSTKEDDLQKLFSKFGEVSEVHVPIdkktkkskGFAYVLFLDPEDAVQAYNELDGKVFQGRLI 74

RNA recognition motif 1 (RRM1) found in vertebrate serine/arginine-rich splicing factor 9 (SRSF9); This subgroup corresponds to the RRM1 of SRSF9, also termed pre-mRNA-splicing factor SRp30C. SRSF9 is an essential splicing regulatory serine/arginine (SR) protein that 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. SRSF9 can also interact with other proteins implicated in alternative splicing, including YB-1, rSLM-1, rSLM-2, E4-ORF4, Nop30, and p32. SRSF9 contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by an unusually short C-terminal RS domains rich in serine-arginine dipeptides.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMKYG-----FAFVDFEDSRDAEDACHDLDG 57
Cdd:cd12598   1 RIYVGNLPSDVREKDLEDLFYKYGRIRDIELKNRrglvpFAFVRFEDPRDAEDAVFGRNG 60

RNA recognition motif (RRM) found in vertebrate serine/arginine-rich splicing factor 3 (SRSF3); This subgroup corresponds to the RRM of SRSF3, also termed pre-mRNA-splicing factor SRp20, a splicing regulatory serine/arginine (SR) protein that 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. SRSF3 can shuttle between the nucleus and cytoplasm. It contains 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 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMKY---GFAFVDFEDSRDAEDACHDLDGKTMEGSSMRlvVEMARGKPR 77
Cdd:cd12645   6 KVYVGNLGNNGNKTELERAFGYYGPLRSVWVARnppGFAFVEFEDPRDAADAVRELDGRTLCGCRVR--VELSNGEKR 81

RNA recognition motif 3 (RRM3) found in RNA-binding protein 19 (RBM19) and RNA recognition motif 2 found in multiple RNA-binding domain-containing protein 1 (MRD1); This subfamily corresponds to the RRM3 of RBM19 and RRM2 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). 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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISM--------KYGFAFVDFEDSRDAEDACHDLDGKTMEGssmRLV 68
Cdd:cd12316   1 RLFVRNLPFTATEDELRELFEAFGKISEVHIpldkqtkrSKGFAFVLFVIPEDAVKAYQELDGSIFQG---RLL 71

RNA recognition motif 2 (RRM2) found in Deleted in azoospermia-associated protein 1 (DAZAP1) and similar proteins; This subfamily corresponds to the RRM2 of DAZAP1 or DAZ-associated protein 1, also termed proline-rich RNA binding protein (Prrp), a multi-functional ubiquitous RNA-binding protein expressed most abundantly in the testis and essential for normal cell growth, development, and spermatogenesis. DAZAP1 is a shuttling protein whose acetylated is predominantly nuclear and the nonacetylated form is in cytoplasm. DAZAP1 also functions as a translational regulator that activates translation in an mRNA-specific manner. DAZAP1 was initially identified as a binding partner of Deleted in Azoospermia (DAZ). It also interacts with numerous hnRNPs, including hnRNP U, hnRNP U like-1, hnRNPA1, hnRNPA/B, and hnRNP D, suggesting DAZAP1 might associate and cooperate with hnRNP particles to regulate adenylate-uridylate-rich elements (AU-rich element or ARE)-containing mRNAs. DAZAP1 contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal proline-rich domain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 71996524   2 PRLYLGKIPYNARERDVERFLKGYGKINNISMKY--------GFAFVDFEDSRDAEDAC----HDLDGKTME 61
Cdd:cd12327   3 KKVFVGGIPHNCGETELRDYFKRYGVVTEVVMMYdaekqrsrGFGFITFEDEQSVDQAVnmhfHDIMGKKVE 74

RNA recognition motif (RRM) found in eukaryotic RNA-binding protein 18 and similar proteins; This subfamily corresponds to the RRM of RBM18, a putative RNA-binding protein containing a well-conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). The biological role of RBM18 remains unclear.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMKY-----------GFAFVDFEDSRDAEDACHDLDGKTMEGSSmrLVVEM 71
Cdd:cd12355   1 RLWIGNLDPRLTEYHLLKLLSKYGKIKKFDFLFhktgplkgqprGYCFVTFETKEEAEKAIECLNGKLALGKK--LVVRW 78

                ..
gi 71996524  72 AR 73
Cdd:cd12355  79 AH 80

RNA recognition motif (RRM) found in heterogeneous nuclear ribonucleoprotein G (hnRNP G), Y chromosome RNA recognition motif 1 (hRBMY), testis-specific heterogeneous nuclear ribonucleoprotein G-T (hnRNP G-T) and similar proteins; This subfamily corresponds to the RRM domain of hnRNP G, also termed glycoprotein p43 or RBMX, an RNA-binding motif protein located on the X chromosome. It is expressed ubiquitously and has been implicated in the splicing control of several pre-mRNAs. Moreover, hnRNP G may function as a regulator of transcription for SREBP-1c and GnRH1. Research has shown that hnRNP G may also act as a tumor-suppressor since it upregulates the Txnip gene and promotes the fidelity of DNA end-joining activity. In addition, hnRNP G appears to play a critical role in proper neural development of zebrafish and frog embryos. The family also includes several paralogs of hnRNP G, such as hRBMY and hnRNP G-T (also termed RNA-binding motif protein, X-linked-like-2). Both, hRBMY and hnRNP G-T, are exclusively expressed in testis and critical for male fertility. Like hnRNP G, hRBMY and hnRNP G-T interact with factors implicated in the regulation of pre-mRNA splicing, such as hTra2-beta1 and T-STAR. Although members in this family share a high conserved N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), they appear to recognize different RNA targets. For instance, hRBMY interacts specifically with a stem-loop structure in which the loop is formed by the sequence CA/UCAA. In contrast, hnRNP G associates with single stranded RNA sequences containing a CCA/C motif. In addition to the RRM, hnRNP G contains a nascent transcripts targeting domain (NTD) in the middle region and a novel auxiliary RNA-binding domain (RBD) in its C-terminal region. The C-terminal RBD exhibits distinct RNA binding specificity, and would play a critical role in the regulation of alternative splicing by hnRNP G.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNIS-MK-------YGFAFVDFEDSRDAEDACHDLDGKTMEG 62
Cdd:cd12382   3 KLFIGGLNTETNEKALEAVFGKYGRIVEVLlMKdretnksRGFAFVTFESPADAKDAARDMNGKELDG 70

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 71996524   4 LYLGKIPYNARERDVERFLKGYGKINN--ISMKY------GFAFVDFEDSRDAEDACHDLDGKTMEGSsmRLVVEMARG 74
Cdd:cd12312   3 LFVRNVADDTRPDDLRREFGRYGPIVDvyIPLDFytrrprGFAYIQFEDVRDAEDALYYLDRTRFLGR--EIEIQFAQG 79

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        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71996524   4 LYLGKIPYNARERDVERFLKGYGKINNISMKY--------GFAFVDFEDSRDAEDACHDLDGKTMEGSsmRLVVEMARG- 74
Cdd:cd12236   4 LFVARLSYDTTESKLRREFEKYGPIKRVRLVRdkktgksrGYAFIEFEHERDMKAAYKHADGKKIDGR--RVLVDVERGr 81

                ....*...
gi 71996524  75 -----KPR 77
Cdd:cd12236  82 tvkgwKPR 89

RNA recognition motif 1 (RRM1) found in yeast regulator of rDNA transcription protein 5 (RRT5) and similar proteins; This subfamily corresponds to the RRM1 of the lineage specific family containing a group of uncharacterized yeast regulators of rDNA transcription protein 5 (RRT5), which may play roles in the modulation of rDNA transcription. RRT5 contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMKY-------------GFAFVDFEDSRDAEDACHDLDGKTMEGSSMRL 67
Cdd:cd12409   1 RVYISNLSYSTTEEELEELLKDYKPVSVLIPSYtvrgfrsrkhrplGIAYAEFSSVEEAEKVVKDLNGKVFKGRKLFV 78

RNA recognition motif (RRM) found in cleavage stimulation factor subunit 2 (CSTF2), yeast ortholog mRNA 3'-end-processing protein RNA15 and similar proteins; This subfamily corresponds to the RRM domain of CSTF2, its tau variant and eukaryotic homologs. CSTF2, also termed cleavage stimulation factor 64 kDa subunit (CstF64), is the vertebrate conterpart of yeast mRNA 3'-end-processing protein RNA15. It is expressed in all somatic tissues and is one of three cleavage stimulatory factor (CstF) subunits required for polyadenylation. CstF64 contains an N-terminal RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a CstF77-binding domain, a repeated MEARA helical region and a conserved C-terminal domain reported to bind the transcription factor PC-4. During polyadenylation, CstF interacts with the pre-mRNA through the RRM of CstF64 at U- or GU-rich sequences within 10 to 30 nucleotides downstream of the cleavage site. CSTF2T, also termed tauCstF64, is a paralog of the X-linked cleavage stimulation factor CstF64 protein that supports polyadenylation in most somatic cells. It is expressed during meiosis and subsequent haploid differentiation in a more limited set of tissues and cell types, largely in meiotic and postmeiotic male germ cells, and to a lesser extent in brain. The loss of CSTF2T will cause male infertility, as it is necessary for spermatogenesis and fertilization. Moreover, CSTF2T is required for expression of genes involved in morphological differentiation of spermatids, as well as for genes having products that function during interaction of motile spermatozoa with eggs. It promotes germ cell-specific patterns of polyadenylation by using its RRM to bind to different sequence elements downstream of polyadenylation sites than does CstF64. The family also includes yeast ortholog mRNA 3'-end-processing protein RNA15 and similar proteins. RNA15 is a core subunit of cleavage factor IA (CFIA), an essential transcriptional 3'-end processing factor from Saccharomyces cerevisiae. RNA recognition by CFIA is mediated by an N-terminal RRM, which is contained in the RNA15 subunit of the complex. The RRM of RNA15 has a strong preference for GU-rich RNAs, mediated by a binding pocket that is entirely conserved in both yeast and vertebrate RNA15 orthologs.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 71996524   4 LYLGKIPYNARERDVERFLKGYGKINNISMKY--------GFAFVDFEDSRDAEDACHDLDGKTMEGSSMR 66
Cdd:cd12398   3 VFVGNIPYDATEEQLKEIFSEVGPVVSFRLVTdretgkpkGYGFCEFRDAETALSAVRNLNGYELNGRPLR 73

RNA recognition motif 2 (RRM2) found in yeast protein gar2 and similar proteins; This subfamily corresponds to the RRM2 of yeast protein gar2, a novel nucleolar protein required for 18S rRNA and 40S ribosomal subunit accumulation. It shares similar domain architecture with nucleolin from vertebrates and NSR1 from Saccharomyces cerevisiae. The highly phosphorylated N-terminal domain of gar2 is made up of highly acidic regions separated from each other by basic sequences, and contains multiple phosphorylation sites. The central domain of gar2 contains two closely adjacent N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The C-terminal RGG (or GAR) domain of gar2 is rich in glycine, arginine and phenylalanine residues.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 71996524   4 LYLGKIPYNARERDVERFLKGYGKINNISMKY--------GFAFVDFEDSRDAEDACHDLDGKTMEGSSMRL 67
Cdd:cd12448   1 LFVGNLPFSATQDALYEAFSQHGSIVSVRLPTdretgqpkGFGYVDFSTIDSAEAAIDALGGEYIDGRPIRL 72

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 71996524   3 RLYLGKIP-YNARERDVERFLKGYGKINNISMKYGFAFVDFEDSRDAEDACHDLDGKTMEGSSMRLVV 69
Cdd:cd12342   1 RLFIGNLPtKRVSKEDLFRIFSPYGHLMQIVIKNAFGFVQFDSPQSCRNAIECEQGEMNRGKKLHLEV 68

RNA recognition motif 3 (RRM3) found in ribonucleoprotein PTB-binding raver-1, raver-2 and similar proteins; This subfamily corresponds to the RRM3 of raver-1 and raver-2. Raver-1 is a ubiquitously expressed heterogeneous nuclear ribonucleoprotein (hnRNP) that serves as a co-repressor of the nucleoplasmic splicing repressor polypyrimidine tract-binding protein (PTB)-directed splicing of select mRNAs. It shuttles between the cytoplasm and the nucleus and can accumulate in the perinucleolar compartment, a dynamic nuclear substructure that harbors PTB. Raver-1 also modulates focal adhesion assembly by binding to the cytoskeletal proteins, including alpha-actinin, vinculin, and metavinculin (an alternatively spliced isoform of vinculin) at adhesion complexes, particularly in differentiated muscle tissue. Raver-2 is a novel member of the heterogeneous nuclear ribonucleoprotein (hnRNP) family. It shows high sequence homology to raver-1. Raver-2 exerts a spatio-temporal expression pattern during embryogenesis and is mainly limited to differentiated neurons and glia cells. Although it displays nucleo-cytoplasmic shuttling in heterokaryons, raver2 localizes to the nucleus in glia cells and neurons. Raver-2 can interact with PTB and may participate in PTB-mediated RNA-processing. However, there is no evidence indicating that raver-2 can bind to cytoplasmic proteins. Both, raver-1 and raver-2, contain three N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), two putative nuclear localization signals (NLS) at the N- and C-termini, a central leucine-rich region, and a C-terminal region harboring two [SG][IL]LGxxP motifs. They binds to RNA through the RRMs. In addition, the two [SG][IL]LGxxP motifs serve as the PTB-binding motifs in raver1. However, raver-2 interacts with PTB through the SLLGEPP motif only.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71996524   4 LYLGKIPYNARERDV-ERFLKGYGKIN--NISMKYG----FAFVDFEDSRDAEDACHDLDGKTMEGSSMR 66
Cdd:cd12390   5 LFVDRLPKDFRDGSElRKLFSQVGKPTfcQLAMGNGvprgFAFVEFASAEDAEEAQQLLNGHDLQGSPIR 74

RNA recognition motif (RRM) found in vertebrate heterogeneous nuclear ribonucleoprotein C1/C2 (hnRNP C1/C2); This subgroup corresponds to the RRM of heterogeneous nuclear ribonucleoprotein C (hnRNP) proteins C1 and C2, 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 hnRNA in the nucleus and in processing of pre-mRNA such as splicing and 3'-end formation. hnRNP C proteins contain two distinct domains, an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal auxiliary domain that includes the variable region, the basic region and the KSG box rich in repeated Lys-Ser-Gly sequences, the leucine zipper, and the acidic region. The RRM is capable of binding poly(U). The KSG box may bind to RNA. The leucine zipper may be involved in dimer formation. The acidic and hydrophilic C-teminus harbors a putative nucleoside triphosphate (NTP)-binding fold and a protein kinase phosphorylation site.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 71996524   3 RLYLGKI-PYNARERDVERFLKGYGKINNISMKYGFAFVDFEDSRDAEDACHDLDGKTMEGSSmrLVVEMArGKPRGN 79
Cdd:cd12603   8 RVFIGNLnTLVVKKSDVEAIFSKYGKIVGCSVHKGFAFVQYVNERNARAAVAGEDGRMIAGQV--LDINLA-AEPKVN 82

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMKYGFAFVDFEDSRDAEDACHDLDGKTMEGSsmRLVVE 70
Cdd:cd12343   1 KIFVGNLPDAATSEELRALFEKYGKVTECDIVKNYAFVHMEKEEDAEDAIKALNGYEFMGS--RINVE 66

RNA recognition motif (RRM) found in serine/arginine-rich splicing factor 10 (SRSF10) and similar proteins; This subgroup corresponds to the RRM of 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). SRSF10 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. It contains 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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 71996524   4 LYLGKIPYNARERDVERFLKGYGKINNISMKY--------GFAFVDFEDSRDAEDACHDLDGKTMEGSSMRL 67
Cdd:cd12559   8 LFVRNVADDTRSEDLRREFGRYGPIVDVYVPLdfytrrprGFAYVQFEDVRDAEDALHNLDRKWICGRQIEI 79

RNA recognition motif 2 (RRM2) found in vertebrate RNA-binding protein RBM23, RBM39 and similar proteins; This subfamily corresponds to the RRM2 of RBM39 (also termed HCC1), a nuclear autoantigen that contains an N-terminal arginine/serine rich (RS) motif and three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). An octapeptide sequence called the RS-ERK motif is repeated six times in the RS region of RBM39. Although the cellular function of RBM23 remains unclear, it shows high sequence homology to RBM39 and contains two RRMs. It may possibly function as a pre-mRNA splicing factor.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 71996524   4 LYLGKIPYNARERDVERFLKGYGKINNISMKY--------GFAFVDFEDSRDAEDACHDLDGKTMEGSSMRL 67
Cdd:cd12284   1 LYVGSLHFNITEDMLRGIFEPFGKIEFVQLQKdpetgrskGYGFIQFRDAEDAKKALEQLNGFELAGRPMKV 72

RNA recognition motif 1 (RRM1) found in vertebrate RNA-binding protein 4 (RBM4); This subgroup corresponds to the RRM1 of RBM4, a ubiquitously expressed splicing factor that has two isoforms, RBM4A (also known as Lark homolog) and RBM4B (also known as RBM30), which are very similar in structure and sequence. RBM4 may function as a translational regulator of stress-associated mRNAs and also plays a role in micro-RNA-mediated gene regulation. RBM4 contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), a CCHC-type zinc finger, and three alanine-rich regions within their C-terminal regions. The C-terminal region may be crucial for nuclear localization and protein-protein interaction. The RRMs, in combination with the C-terminal region, are responsible for the splicing function of RBM4.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMKYGFAFVDFEDSRDAEDACHDLDGKTMEGSSM 65
Cdd:cd12606   2 KLFIGNLPREATEEEIRSLFEQYGKVTECDIIKNYGFVHMEDKSAADEAIRNLHHYKLHGVAI 64

RNA recognition motif 1 (RRM1) found in the p54nrb/PSF/PSP1 family; This subfamily corresponds to the RRM1 of the p54nrb/PSF/PSP1 family, including 54 kDa nuclear RNA- and DNA-binding protein (p54nrb or NonO or NMT55), polypyrimidine tract-binding protein (PTB)-associated-splicing factor (PSF or POMp100), paraspeckle protein 1 (PSP1 or PSPC1), which are ubiquitously expressed and are conserved in vertebrates. p54nrb is a multi-functional protein involved in numerous nuclear processes including transcriptional regulation, splicing, DNA unwinding, nuclear retention of hyperedited double-stranded RNA, viral RNA processing, control of cell proliferation, and circadian rhythm maintenance. PSF is also a multi-functional protein that binds RNA, single-stranded DNA (ssDNA), double-stranded DNA (dsDNA) and many factors, and mediates diverse activities in the cell. PSP1 is a novel nucleolar factor that accumulates within a new nucleoplasmic compartment, termed paraspeckles, and diffusely distributes in the nucleoplasm. The cellular function of PSP1 remains unknown currently. This subfamily also includes some p54nrb/PSF/PSP1 homologs from invertebrate species, such as the Drosophila melanogaster gene no-ontransient A (nonA) encoding puff-specific protein Bj6 (also termed NONA) and Chironomus tentans hrp65 gene encoding protein Hrp65. D. melanogaster NONA is involved in eye development and behavior, and may play a role in circadian rhythm maintenance, similar to vertebrate p54nrb. C. tentans Hrp65 is a component of nuclear fibers associated with ribonucleoprotein particles in transit from the gene to the nuclear pore. All family members contain a DBHS domain (for Drosophila behavior, human splicing), which comprises two conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a charged protein-protein interaction module. PSF has an additional large N-terminal domain that differentiates it from other family members.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINN--ISMKYGFAFVDFEDSRDAEDACHDLDGKTMEGSSMR 66
Cdd:cd12332   3 RLFVGNLPNDITEEEFKELFQKYGEVSEvfLNKGKGFGFIRLDTRANAEAAKAELDGTPRKGRQLR 68

RNA recognition motif (RRM) found in heterogeneous nuclear ribonucleoprotein (hnRNP) H protein family, epithelial splicing regulatory proteins (ESRPs), Drosophila RNA-binding protein Fusilli, RNA-binding protein 12 (RBM12) and similar proteins; The family includes RRM domains in the hnRNP H protein family, G-rich sequence factor 1 (GRSF-1), ESRPs (also termed RBM35), Drosophila Fusilli, RBM12 (also termed SWAN), RBM12B, RBM19 (also termed RBD-1) and similar proteins. The hnRNP H protein family includes hnRNP H (also termed mcs94-1), hnRNP H2 (also termed FTP-3 or hnRNP H'), hnRNP F and hnRNP H3 (also termed hnRNP 2H9), which represent a group of nuclear RNA binding proteins that are involved in pre-mRNA processing. GRSF-1 is a cytoplasmic poly(A)+ mRNA binding protein which interacts with RNA in a G-rich element-dependent manner. It may function in RNA packaging, stabilization of RNA secondary structure, or other macromolecular interactions. ESRP1 (also termed RBM35A) and ESRP2 (also termed RBM35B) are epithelial-specific RNA binding proteins that promote splicing of the epithelial variant of fibroblast growth factor receptor 2 (FGFR2), ENAH (also termed hMena), CD44 and CTNND1 (also termed p120-Catenin) transcripts. Fusilli shows high sequence homology to ESRPs. It can regulate endogenous FGFR2 splicing and functions as a splicing factor. The biological roles of both, RBM12 and RBM12B, remain unclear. RBM19 is a nucleolar protein conserved in eukaryotes. It is involved in ribosome biogenesis by processing rRNA. In addition, it is essential for preimplantation development. Members in this family contain 2~6 conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 71996524   9 IPYNARERDVERFLKGYGKI-NNISMKY-------GFAFVDFEDSRDAEDAC 52
Cdd:cd12254   7 LPFSATEEDIRDFFSGLDIPpDGIHIVYdddgrptGEAYVEFASEEDAQRAL 58

RNA recognition motif 2 (RRM2) found in yeast nucleolar protein 13 (Nop13p) and similar proteins; This subfamily corresponds to the RRM2 of Nop13p encoded by YNL175c from Saccharomyces cerevisiae. It shares high sequence similarity with nucleolar protein 12 (Nop12p). Both Nop12p and Nop13p are not essential for growth. However, unlike Nop12p that is localized to the nucleolus, Nop13p localizes primarily to the nucleolus but is also present in the nucleoplasm to a lesser extent. Nop13p contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 71996524   4 LYLGKIPYNARERDVERFLKGYGKINNISMKY--------GFAFVDFEDSRDAEDACHDLDGKTMEGSSMRL 67
Cdd:cd12397   1 LFVGNLSFETTEEDLRKHFAPAGKIRKVRMATfedsgkckGFAFVDFKEIESATNAVKGPINHSLNGRDLRV 72

RNA recognition motif (RRM) found in cold inducible RNA binding protein (CIRBP), RNA binding motif protein 3 (RBM3) and similar proteins; This subfamily corresponds to the RRM domain of two structurally related heterogenous nuclear ribonucleoproteins, CIRBP (also termed CIRP or A18 hnRNP) and RBM3 (also termed RNPL), both of which belong to a highly conserved cold shock proteins family. The cold shock proteins can be induced after exposure to a moderate cold-shock and other cellular stresses such as UV radiation and hypoxia. CIRBP and RBM3 may function in posttranscriptional regulation of gene expression by binding to different transcripts, thus allowing the cell to response rapidly to environmental signals. However, the kinetics and degree of cold induction are different between CIRBP and RBM3. Tissue distribution of their expression is different. CIRBP and RBM3 may be differentially regulated under physiological and stress conditions and may play distinct roles in cold responses of cells. CIRBP, also termed glycine-rich RNA-binding protein CIRP, is localized in the nucleus and mediates the cold-induced suppression of cell cycle progression. CIRBP also binds DNA and possibly serves as a chaperone that assists in the folding/unfolding, assembly/disassembly and transport of various proteins. RBM3 may enhance global protein synthesis and the formation of active polysomes while reducing the levels of ribonucleoprotein complexes containing microRNAs. RBM3 may also serve to prevent the loss of muscle mass by its ability to decrease cell death. Furthermore, RBM3 may be essential for cell proliferation and mitosis. Both, CIRBP and RBM3, contain an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), that is involved in RNA binding, and C-terminal glycine-rich domain (RGG motif) that probably enhances RNA-binding via protein-protein and/or protein-RNA interactions. Like CIRBP, RBM3 can also bind to both RNA and DNA via its RRM domain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISM--------KYGFAFVDFEDSRDAEDACHDLDGKTMEGSSMRL 67
Cdd:cd12449   2 KLFVGGLSFDTNEQSLEEVFSKYGQISEVVVvkdretqrSRGFGFVTFENPDDAKDAMMAMNGKSLDGRQIRV 74

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.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|...
gi 71996524  23 KGYGKINNISMKY-------GFAFVDFEDSRDAEDACHDLDGK 58
Cdd:cd12278  31 FGSGKIVGIYMPVdetgktkGFAFVEYATPEEAKKAVKALNGY 73

RNA recognition motif 1 (RRM1) found in vertebrate 54 kDa nuclear RNA- and DNA-binding protein (p54nrb); This subgroup corresponds to the RRM1 of p54nrb, also termed non-POU domain-containing octamer-binding protein (NonO), or 55 kDa nuclear protein (NMT55), or DNA-binding p52/p100 complex 52 kDa subunit. p54nrb is a multifunctional protein involved in numerous nuclear processes including transcriptional regulation, splicing, DNA unwinding, nuclear retention of hyperedited double-stranded RNA, viral RNA processing, control of cell proliferation, and circadian rhythm maintenance. It is ubiquitously expressed and highly conserved in vertebrates. p54nrb binds both, single- and double-stranded RNA and DNA, and also possesses inherent carbonic anhydrase activity. It forms a heterodimer with paraspeckle component 1 (PSPC1 or PSP1), localizing to paraspeckles in an RNA-dependent manneras well as with polypyrimidine tract-binding protein-associated-splicing factor (PSF). p54nrb contains two conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), at the N-terminus.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 71996524   3 RLYLGKIPYNARERDVERFLKGYGKINNISMK--YGFAFVDFEDSRDAEDACHDLDGKTMEGSSMRL 67
Cdd:cd12588   3 RLFVGNLPPDITEEEMRKLFEKYGKAGEVFIHkdKGFGFIRLETRTLAEIAKVELDNMPLRGKQLRV 69

U2 snRNP auxilliary factor, large subunit, splicing factor; These splicing factors consist of an N-terminal arginine-rich low complexity domain followed by three tandem RNA recognition motifs (pfam00076). The well-characterized members of this family are auxilliary components of the U2 small nuclear ribonuclearprotein splicing factor (U2AF). These proteins are closely related to the CC1-like subfamily of splicing factors (TIGR01622). Members of this subfamily are found in plants, metazoa and fungi.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 71996524     3 RLYLGKIPYNARERDVERFLKGYG--------KINNISMKYGFAFVDFEDSRDAEDACHDLDGKTM 60
Cdd:TIGR01642 297 RIYIGNLPLYLGEDQIKELLESFGdlkafnliKDIATGLSKGYAFCEYKDPSVTDVAIAALNGKDT 362

RNA recognition motif 1 in La autoantigen (La or LARP3) and similar proteins; This subfamily corresponds to the RRM1 of La autoantigen, also termed Lupus La protein, or La ribonucleoprotein, or Sjoegren syndrome type B antigen (SS-B), a highly abundant nuclear phosphoprotein and well conserved in eukaryotes. It specifically binds the 3'-terminal UUU-OH motif of nascent RNA polymerase III transcripts and protects them from exonucleolytic degradation by 3' exonucleases. In addition, La can directly facilitate the translation and/or metabolism of many UUU-3' OH-lacking cellular and viral mRNAs, through binding internal RNA sequences within the untranslated regions of target mRNAs. La contains an N-terminal La motif (LAM), followed by two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). It also possesses a short basic motif (SBM) and a nuclear localization signal (NLS) at the C-terminus.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*...
gi 71996524  10 PYNARERDVERFLKGYGKINNISMKY--------GFAFVDFEDSRDAE 49
Cdd:cd12291   8 PLDATLDDIQEFFEKKGKVENVRMRRdldskefkGSVFVEFKTEEEAK 55

RNA recognition motif in nucleolar protein interacting with the FHA domain of pKI-67 (NIFK) and similar proteins; This subgroup corresponds to the RRM of NIFK and Nop15p. NIFK, also termed MKI67 FHA domain-interacting nucleolar phosphoprotein, or nucleolar phosphoprotein Nopp34, is a putative RNA-binding protein interacting with the forkhead associated (FHA) domain of pKi-67 antigen in a mitosis-specific and phosphorylation-dependent manner. It is nucleolar in interphase but associates with condensed mitotic chromosomes. This family also includes Saccharomyces cerevisiae YNL110C gene encoding ribosome biogenesis protein 15 (Nop15p), also termed nucleolar protein 15. Both, NIFK and Nop15p, contain an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain).

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gi 71996524   4 LYLGKIPYNARERDVERFLKGYGKINNI----SMKYG----FAFVDFEDSRDAEDACHDLDGKTMEG 62
Cdd:cd12307   2 VYIGHLPHGFYEPELRKYFSQFGTVTRLrlsrSKKTGkskgYAFVEFEDPEVAKIVAETMNNYLLFE 68

RNA recognition motif 3 (RRM3) found in the Spen (split end) protein family; This subfamily corresponds to the RRM3 domain in the Spen (split end) protein family which includes RNA binding motif protein 15 (RBM15), putative RNA binding motif protein 15B (RBM15B) and similar proteins found in Metazoa. RBM15, also termed one-twenty two protein 1 (OTT1), conserved in eukaryotes, is a novel mRNA export factor and is a novel component of the NXF1 pathway. It binds to NXF1 and serves as receptor for the RNA export element RTE. It also possess mRNA export activity and can facilitate the access of DEAD-box protein DBP5 to mRNA at the nuclear pore complex (NPC). RNA-binding protein 15B (RBM15B), also termed one twenty-two 3 (OTT3), is a paralog of RBM15 and therefore has post-transcriptional regulatory activity. It is a nuclear protein sharing with RBM15 the association with the splicing factor compartment and the nuclear envelope as well as the binding to mRNA export factors NXF1 and Aly/REF. Members in this family belong to the Spen (split end) protein family, which shares a domain architecture comprising of three N-terminal RNA recognition motifs (RRMs), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal SPOC (Spen paralog and ortholog C-terminal) domain.

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gi 71996524   9 IPYNARERDVERFlkgyGKINNISMKYG--FAFVDFEDSRDAEDACHDLDGKTMEGSSMRLVVEMA 72
Cdd:cd12310  10 TSLAELEREFDRF----GAIRKIDYRKGddYAYILYESLDAAQAAVRALRGFPLGGPDRRLRVDFA 71

RNA recognition motif 3 (RRM3) found in vertebrate heterogeneous nuclear ribonucleoprotein R (hnRNP R); This subgroup corresponds to the RRM3 of hnRNP R. a ubiquitously expressed nuclear RNA-binding protein that specifically bind mRNAs with a preference for poly(U) stretches. Upon binding of RNA, hnRNP R forms oligomers, most probably dimers. hnRNP R has been implicated in mRNA processing and mRNA transport, and also acts as a regulator to modify binding to ribosomes and RNA translation. hnRNP R is predominantly located in axons of motor neurons and to a much lower degree in sensory axons. In axons of motor neurons, it also functions as a cytosolic protein and interacts with wild type of survival motor neuron (SMN) proteins directly, further providing a molecular link between SMN and the spliceosome. Moreover, hnRNP R plays an important role in neural differentiation and development, as well as in retinal development and light-elicited cellular activities. hnRNP R contains an acidic auxiliary N-terminal region, followed by two well-defined and one degenerated RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal RGG motif; hnRNP R binds RNA through its RRM domains.

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gi 71996524   4 LYLGKIPYNARERDVERFLKGYGKINNISMKYGFAFVDFEDSRDAEDACHDLDGKTMEGSSMRLVV 69
Cdd:cd12494   4 LFVRNLATTVTEEILEKTFSQFGKLERVKKLKDYAFVHFEDRDAAVKAMDEMNGKEVEGEEIEIVL 69

RNA recognition motif (RRM) found in eukaryotic translation initiation factor 4H (eIF-4H) and similar proteins; This subfamily corresponds to the RRM of eIF-4H, also termed Williams-Beuren syndrome chromosomal region 1 protein, which, together with elf-4B/eIF-4G, serves as the accessory protein of RNA helicase eIF-4A. eIF-4H contains a well conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain). It stimulates protein synthesis by enhancing the helicase activity of eIF-4A in the initiation step of mRNA translation.

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gi 71996524   5 YLGKIPYNARERDVERFLKGYgKINNISM-------KY-GFAFVDFEDSRDAEDAChDLDGKTMEGSSMRlvVEMARGK 75
Cdd:cd12401   9 YVGNLPFNTVQGDLDAIFKDL-KVRSVRLvrdretdKFkGFCYVEFEDLESLKEAL-EYDGALFEDRPLR--VDIAEGR 83

RNA recognition motif 1 in fungal pre-messenger RNA splicing protein 24 (Prp24) and similar proteins; This subfamily corresponds to the RRM1 of Prp24, also termed U4/U6 snRNA-associated-splicing factor PRP24 (U4/U6 snRNP), an RNA-binding protein with four well conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). It facilitates U6 RNA base-pairing with U4 RNA during spliceosome assembly. Prp24 specifically binds free U6 RNA primarily with RRMs 1 and 2 and facilitates pairing of U6 RNA bases with U4 RNA bases. Additionally, it may also be involved in dissociation of the U4/U6 complex during spliceosome activation.