ribonuclease E; Reviewed

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                   ....*....|....*....|....*....|....*....|....*
gi 1972263954    2 SGARRDNRRSNGRD-DSSRVAKAENDRKPGRENRggDEKRGNSNN 45
Cdd:PRK10811   603 QQDRRKPRQNNRRDrNERRDTRDNRTRREGRENR--EENRRNRRQ 645

RNA recognition motif;

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|....*
gi 1972263954  117 RLFVGNLPNEVKETELKELFSPHGDIAECYL-------SGKGFAF 154
Cdd:smart00360   1 TLFVGNLPPDTTEEELRELFSKFGKVESVRLvrdketgKSKGFAF 45

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
                  ....*....|....*....|....*....|....*....|....*
gi 1972263954 118 LFVGNLPNEVKETELKELFSPHGDIAECYL------SGKGFAFLR 156
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGPIKSIRLvrdetgRSKGFAFVE 45

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
                  ....*....|....*....|....*....|....*
gi 1972263954 108 PKKKFTGrcrLFVGNLPNEVKETELKELFSPHGDI 142
Cdd:TIGR01628 174 PLKKFTN---LYVKNLDPSVNEDKLRELFAKFGEI 205

RNA recognition motif 1 (RRM1) found in vertebrate polypyrimidine tract-binding protein (PTB)-associated-splicing factor (PSF); This subgroup corresponds to the RRM1 of PSF, also termed proline- and glutamine-rich splicing factor, or 100 kDa DNA-pairing protein (POMp100), or 100 kDa subunit of DNA-binding p52/p100 complex, a multifunctional protein that mediates diverse activities in the cell. It is ubiquitously expressed and highly conserved in vertebrates. PSF binds not only RNA but also both single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA) and facilitates the renaturation of complementary ssDNAs. Besides, it promotes the formation of D-loops in superhelical duplex DNA, and is involved in cell proliferation. PSF can also interact with multiple factors. It is an RNA-binding component of spliceosomes and binds to insulin-like growth factor response element (IGFRE). PSF functions as a transcriptional repressor interacting with Sin3A and mediating silencing through the recruitment of histone deacetylases (HDACs) to the DNA binding domain (DBD) of nuclear hormone receptors. Additionally, PSF is an essential pre-mRNA splicing factor and is dissociated from PTB and binds to U1-70K and serine-arginine (SR) proteins during apoptosis. PSF forms a heterodimer with the nuclear protein p54nrb, also known as non-POU domain-containing octamer-binding protein (NonO). The PSF/p54nrb complex displays a variety of functions, such as DNA recombination and RNA synthesis, processing, and transport. PSF contains two conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), which are responsible for interactions with RNA and for the localization of the protein in speckles. It also contains an N-terminal region rich in proline, glycine, and glutamine residues, which may play a role in interactions recruiting other molecules.

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                  ....*....|....*....|....*....|....*....|....*...
gi 1972263954 115 RCRLFVGNLPNEVKETELKELFSPHGDIAECYLS-GKGFAFLRLISNA 161
Cdd:cd12587     1 RCRLFVGNLPADITEDEFKRLFAKYGEPGEVFINkGKGFGFIKLESRA 48

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

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYL-----SG--KGFAF 154
Cdd:COG0724     3 KIYVGNLPYSVTEEDLRELFSEYGEVTSVKLitdreTGrsRGFGF 47

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
                  ....*....|....*....|....*....|....*....|....*
gi 1972263954 118 LFVGNLPNEVKETELKELFSPHGDIAECYL------SGKGFAFLR 156
Cdd:cd00590     1 LFVGNLPPDTTEEDLRELFSKFGEVVSVRIvrdrdgKSKGFAFVE 45

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYL-------SGKGFAFLR-LISNAANK 164
Cdd:cd12316     1 RLFVRNLPFTATEDELRELFEAFGKISEVHIpldkqtkRSKGFAFVLfVIPEDAVK 56

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.

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                  ....*....|....*....|....*....|....*....|....
gi 1972263954 115 RCRLFVGNLPNEVKETELKELFSPHGDIAECYLS-GKGFAFLRL 157
Cdd:cd12588     1 RSRLFVGNLPPDITEEEMRKLFEKYGKAGEVFIHkDKGFGFIRL 44

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 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYLSgKGFAF 154
Cdd:cd12343     1 KIFVGNLPDAATSEELRALFEKYGKVTECDIV-KNYAF 37

RNA recognition motif 1 (RRM1) and 2 (RRM2) found in CELF/Bruno-like family of RNA binding proteins and plant flowering time control protein FCA; This subfamily corresponds to the RRM1 and RRM2 domains of the CUGBP1 and ETR-3-like factors (CELF) as well as plant flowering time control protein FCA. CELF, also termed BRUNOL (Bruno-like) proteins, is a family of structurally related RNA-binding proteins involved in regulation of pre-mRNA splicing in the nucleus, and control of mRNA translation and deadenylation in the cytoplasm. The family contains six members: CELF-1 (also known as BRUNOL-2, CUG-BP1, NAPOR, EDEN-BP), CELF-2 (also known as BRUNOL-3, ETR-3, CUG-BP2, NAPOR-2), CELF-3 (also known as BRUNOL-1, TNRC4, ETR-1, CAGH4, ER DA4), CELF-4 (BRUNOL-4), CELF-5 (BRUNOL-5) and CELF-6 (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. This subfamily also includes plant flowering time control protein FCA that functions in the posttranscriptional regulation of transcripts involved in the flowering process. FCA contains two RRMs, and a WW protein interaction domain.

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                  ....*....|....*....|....*....|....*....|....*.
gi 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYL-------SGKGFAFL 155
Cdd:cd12361     1 KLFVGMIPKTASEEDVRPLFEQFGNIEEVQIlrdkqtgQSKGCAFV 46

RNA recognition motif (RRM) found in nucleolar protein 8 (NOL8) and similar proteins; This model corresponds to the RRM of NOL8 (also termed Nop132) encoded by a novel NOL8 gene that is up-regulated in the majority of diffuse-type, but not intestinal-type, gastric cancers. Thus, NOL8 may be a good molecular target for treatment of diffuse-type gastric cancer. Also, NOL8 is a phosphorylated protein that contains an N-terminal RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), suggesting NOL8 is likely to function as a novel RNA-binding protein. It may be involved in regulation of gene expression at the post-transcriptional level or in ribosome biogenesis in cancer cells.

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                  ....*....|....*....|....*....|....*....|....*....|...
gi 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYL------SGKGFAFLRLISNAAN 163
Cdd:cd12226     1 RLFVGGLSPSITEDDLERRFSRFGTVSDVEIirkkdaPDRGFAYIDLRTSEAA 53

RNA recognition motif 1 (RRM1) found in RNA-binding protein 19 (RBM19) and similar proteins; This subgroup corresponds to the RRM1 of RBM19, also termed RNA-binding domain-1 (RBD-1), a nucleolar protein conserved in eukaryotes. It is involved in ribosome biogenesis by processing rRNA. In addition, it is essential for preimplantation development. RBM19 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 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYL----SGK--GFAF 154
Cdd:cd12564     2 RLIVKNLPSSITEDRLRKLFSAFGTITDVQLkytkDGKfrRFGF 45

RNA recognition motif 3 (RRM3) found in RNA-binding protein 19 (RBM19) and similar proteins; This subgroup corresponds to the RRM3 of RBM19, also termed RNA-binding domain-1 (RBD-1), which is a nucleolar protein conserved in eukaryotes. It is involved in ribosome biogenesis by processing rRNA. In addition, it is essential for preimplantation development. RBM19 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 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYL-------SGKGFAFL 155
Cdd:cd12567     4 RLFVRNLPYTCTEEDLEKLFSKYGPLSEVHFpidsltkKPKGFAFV 49

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.

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gi 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYL-----SG--KGFAFL 155
Cdd:cd21608     1 KLYVGNLSWDTTEDDLRDLFSEFGEVESAKVitdreTGrsRGFGFV 46

RNA recognition motif (RRM) found in ras GTPase-activating protein-binding protein G3BP1, G3BP2 and similar proteins; This subfamily corresponds to the RRM domain in the G3BP family of RNA-binding and SH3 domain-binding proteins. G3BP acts at the level of RNA metabolism in response to cell signaling, possibly as RNA transcript stabilizing factors or an RNase. Members include G3BP1, G3BP2 and similar proteins. These proteins associate directly with the SH3 domain of GTPase-activating protein (GAP), which functions as an inhibitor of Ras. They all contain an N-terminal nuclear transfer factor 2 (NTF2)-like domain, an acidic domain, a domain containing PXXP motif(s), an RNA recognition motif (RRM), and an Arg-Gly-rich region (RGG-rich region, or arginine methylation motif).

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                  ....*....|....*....|....*....|....*
gi 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYLSGKG 151
Cdd:cd12229     5 QLFVGNLPHDITEDELKEFFSRFGNVLELRINSKG 39

RNA recognition motif (RRM) found in ras GTPase-activating protein-binding protein 1 (G3BP1) and similar proteins; This subgroup corresponds to the RRM of G3BP1, also termed ATP-dependent DNA helicase VIII (DH VIII), or GAP SH3 domain-binding protein 1, which has been identified as a phosphorylation-dependent endoribonuclease that interacts with the SH3 domain of RasGAP, a multi-functional protein controlling Ras activity. The acidic RasGAP binding domain of G3BP1 harbors an arsenite-regulated phosphorylation site and dominantly inhibits stress granule (SG) formation. G3BP1 also contains an N-terminal nuclear transfer factor 2 (NTF2)-like domain, an RNA recognition motif (RRM domain), and an Arg-Gly-rich region (RGG-rich region, or arginine methylation motif). The RRM domain and RGG-rich region are canonically associated with RNA binding. G3BP1 co-immunoprecipitates with mRNAs. It binds to and cleaves the 3'-untranslated region (3'-UTR) of the c-myc mRNA in a phosphorylation-dependent manner. Thus, G3BP1 may play a role in coupling extra-cellular stimuli to mRNA stability. It has been shown that G3BP1 is a novel Dishevelled-associated protein that is methylated upon Wnt3a stimulation and that arginine methylation of G3BP1 regulates both Ctnnb1 mRNA and canonical Wnt/beta-catenin signaling. Furthermore, G3BP1 can be associated with the 3'-UTR of beta-F1 mRNA in cytoplasmic RNA-granules, demonstrating that G3BP1 may specifically repress the translation of the transcript.

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                  ....*....|....*....|....*....|....*
gi 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYLSGKG 151
Cdd:cd12463     5 QLFVGNLPHDVDKSELKEFFQGYGNVVELRINSGG 39

RNA recognition motif 2 (RRM2) found in RNA-binding protein 28 (RBM28) and similar proteins; This subfamily corresponds to the RRM2 of RBM28 and Nop4p. RBM28 is a specific nucleolar component of the spliceosomal small nuclear ribonucleoproteins (snRNPs), possibly coordinating their transition through the nucleolus. It specifically associates with U1, U2, U4, U5, and U6 small nuclear RNAs (snRNAs), and may play a role in the maturation of both small nuclear and ribosomal RNAs. RBM28 has four RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and an extremely acidic region between RRM2 and RRM3. The family also includes nucleolar protein 4 (Nop4p or Nop77p) encoded by YPL043W from Saccharomyces cerevisiae. It is an essential nucleolar protein involved in processing and maturation of 27S pre-rRNA and biogenesis of 60S ribosomal subunits. Nop4p also contains four RRMs.

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gi 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYL------SGKGFAF 154
Cdd:cd12414     1 RLIVRNLPFKCTEDDLKKLFSKFGKVLEVTIpkkpdgKLRGFAF 44

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.

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gi 1972263954 118 LFVGNLPNEVKETELKELFSPHGDIAECYL-----SG--KGFAFL 155
Cdd:cd12448     1 LFVGNLPFSATQDALYEAFSQHGSIVSVRLptdreTGqpKGFGYV 45

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).

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                  ....*....|....*....|....*....|....*....|....
gi 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAE----CYLSG--KGFAF 154
Cdd:cd12392     4 KLFVKGLPFSCTKEELEELFKQHGTVKDvrlvTYRNGkpKGLAY 47

RNA recognition motif 2 (RRM2) found in RNA-binding protein 34 (RBM34) and similar proteins; This subfamily corresponds to the RRM2 of RBM34, a putative RNA-binding protein containing two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). Although the function of RBM34 remains unclear currently, its RRM domains may participate in mRNA processing. RBM34 may act as an mRNA processing-related protein.

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                  ....*....|....*....|....*....|....*....|...
gi 1972263954 119 FVGNLPNEVKETELKELFSPHGDIAECYL-------SGKGFAF 154
Cdd:cd12395     3 FVGNLPFDIEEEELRKHFEDCGDVEAVRIvrdretgIGKGFGY 45

RNA recognition motif 2 (RRM2) found in ribonucleoprotein PTB-binding raver-1, raver-2 and similar proteins; This subfamily corresponds to the RRM2 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.

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                  ....*....|....*....|....*....|....*....|....*....|..
gi 1972263954 118 LFVGNLPNEVKETELKELFSPHGDIAECYL-------SGKGFAFLRLISNAA 162
Cdd:cd12389     2 LCVTNLPLSFTEEQFEELVRPYGNVERCFLvysevtgESKGYGFVEYTSKES 53

RNA recognition motif 1 (RRM1) found in RNA-binding protein 28 (RBM28) and similar proteins; This subfamily corresponds to the RRM1 of RBM28 and Nop4p. RBM28 is a specific nucleolar component of the spliceosomal small nuclear ribonucleoproteins (snRNPs), possibly coordinating their transition through the nucleolus. It specifically associates with U1, U2, U4, U5, and U6 small nuclear RNAs (snRNAs), and may play a role in the maturation of both small nuclear and ribosomal RNAs. RBM28 has four RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and an extremely acidic region between RRM2 and RRM3. The family also includes nucleolar protein 4 (Nop4p or Nop77p) encoded by YPL043W from Saccharomyces cerevisiae. It is an essential nucleolar protein involved in processing and maturation of 27S pre-rRNA and biogenesis of 60S ribosomal subunits. Nop4p also contains four RRMs.

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                  ....*....|....*....|....*....|....*....|....*
gi 1972263954 118 LFVGNLPNEVKETELKELFSPHGDIAECYL-------SGKGFAFL 155
Cdd:cd12413     2 LFVRNLPYDTTDEQLEELFSDVGPVKRCFVvkdkgkdKCRGFGYV 46

RNA recognition motif (RRM) found in U11/U12 small nuclear ribonucleoprotein 35 kDa protein (U11/U12-35K) and similar proteins; This subfamily corresponds to the RRM of U11/U12-35K, also termed protein HM-1, or U1 snRNP-binding protein homolog, and is one of the components of the U11/U12 snRNP, which is a subunit of the minor (U12-dependent) spliceosome required for splicing U12-type nuclear pre-mRNA introns. U11/U12-35K is highly conserved among bilateria and plants, but lacks in some organisms, such as Saccharomyces cerevisiae and Caenorhabditis elegans. Moreover, U11/U12-35K shows significant sequence homology to U1 snRNP-specific 70 kDa protein (U1-70K or snRNP70). It contains a conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), followed by an adjacent glycine-rich region, and Arg-Asp and Arg-Glu dipeptide repeats rich domain, making U11/U12-35K a possible functional analog of U1-70K. It may facilitate 5' splice site recognition in the minor spliceosome and play a role in exon bridging, interacting with components of the major spliceosome bound to the pyrimidine tract of an upstream U2-type intron. The family corresponds to the RRM of U11/U12-35K that may directly contact the U11 or U12 snRNA through the RRM domain.

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                  ....*....|....*....|....*....|....*....|....*...
gi 1972263954 115 RCRLFVGNLPNEVKETELKELFSPHGDIAECYL-------SGKGFAFL 155
Cdd:cd12237     4 RLTLFVGRLSLQTTEEKLKEVFSRYGDIRRLRLvrdivtgFSKRYAFI 51

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 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYL------SGKGFAF 154
Cdd:cd12412     4 RIFVGGIDWDTTEEELREFFSKFGKVKDVKIikdragVSKGYGF 47

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 1972263954 118 LFVGNLPNEVKETELKELFSPHGDIAECYL----SGK--GFAF 154
Cdd:cd12380     4 VYVKNFGEDVDDDELKELFEKYGKITSAKVmkddSGKskGFGF 46

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
                  ....*....|....*....|....*.
gi 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDI 142
Cdd:cd12599     1 RVYVGNLPMDIREREVEDLFSKYGPV 26

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.

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                  ....*....|....*....|....*....|....*....|....*.
gi 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYL-------SGKGFAFL 155
Cdd:cd12382     3 KLFIGGLNTETNEKALEAVFGKYGRIVEVLLmkdretnKSRGFAFV 48

RNA recognition motif 1 (RRM1) found in Mei2-like proteins and terminal EAR1-like proteins; This subfamily corresponds to the RRM1 of Mei2-like proteins from plant and fungi, terminal EAR1-like proteins from plant, and other eukaryotic homologs. Mei2-like proteins represent an ancient eukaryotic RNA-binding protein family whose corresponding Mei2-like genes appear to have arisen early in eukaryote evolution, been lost from some lineages such as Saccharomyces cerevisiae and metazoans, and diversified in the plant lineage. The plant Mei2-like genes may function in cell fate specification during development, rather than as stimulators of meiosis. In the fission yeast Schizosaccharomyces pombe, the Mei2 protein is an essential component of the switch from mitotic to meiotic growth. S. pombe Mei2 stimulates meiosis in the nucleus upon binding a specific non-coding RNA. The terminal EAR1-like protein 1 and 2 (TEL1 and TEL2) are mainly found in land plants. They may play a role in the regulation of leaf initiation. All members in this family are putative RNA-binding proteins carrying three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). In addition to the RRMs, the terminal EAR1-like proteins also contain TEL characteristic motifs that allow sequence and putative functional discrimination between them and Mei2-like proteins.

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                  ....*....|....*....|....*....|...
gi 1972263954 118 LFVGNLPNEVKETELKELFSPHGDIAECYLSGK 150
Cdd:cd12275     4 LFVINVPRDVTESTLRRLFEVYGDVRGVQTERI 36

RNA recognition motif (RRM) found in SRA stem-loop-interacting RNA-binding protein (SLIRP) and similar proteins; This subfamily corresponds to the RRM of SLIRP, a widely expressed small steroid receptor RNA activator (SRA) binding protein, which binds to STR7, a functional substructure of SRA. SLIRP is localized predominantly to the mitochondria and plays a key role in modulating several nuclear receptor (NR) pathways. It functions as a co-repressor to repress SRA-mediated nuclear receptor coactivation. It modulates SHARP- and SKIP-mediated co-regulation of NR activity. SLIRP contains an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), which is required for SLIRP's corepression activities.

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                  ....*....|....*....|....*....|....*....|....*.
gi 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAECYL-----SG--KGFAFL 155
Cdd:cd12242     1 KLFVSNLPWTTGSSELKEYFSQFGKVKRCNLpfdkeTGfhKGFGFV 46

RNA recognition motif 3 (RRM3) found in the Hu proteins family; This subfamily corresponds to the RRM3 of the Hu proteins family which represent a group of RNA-binding proteins involved in diverse biological processes. Since the Hu proteins share high homology with the Drosophila embryonic lethal abnormal vision (ELAV) protein, the Hu family is sometimes referred to as the ELAV family. Drosophila ELAV is exclusively expressed in neurons and is required for the correct differentiation and survival of neurons in flies. The neuronal members of the Hu family include Hu-antigen B (HuB or ELAV-2 or Hel-N1), Hu-antigen C (HuC or ELAV-3 or PLE21), and Hu-antigen D (HuD or ELAV-4), which play important roles in neuronal differentiation, plasticity and memory. HuB is also expressed in gonads. Hu-antigen R (HuR or ELAV-1 or HuA) is the ubiquitously expressed Hu family member. It has a variety of biological functions mostly related to the regulation of cellular response to DNA damage and other types of stress. Hu proteins perform their cytoplasmic and nuclear molecular functions by coordinately regulating functionally related mRNAs. In the cytoplasm, Hu proteins recognize and bind to AU-rich RNA elements (AREs) in the 3' untranslated regions (UTRs) of certain target mRNAs, such as GAP-43, vascular epithelial growth factor (VEGF), the glucose transporter GLUT1, eotaxin and c-fos, and stabilize those ARE-containing mRNAs. They also bind and regulate the translation of some target mRNAs, such as neurofilament M, GLUT1, and p27. In the nucleus, Hu proteins function as regulators of polyadenylation and alternative splicing. Each Hu protein contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). RRM1 and RRM2 may cooperate in binding to an ARE. RRM3 may help to maintain the stability of the RNA-protein complex, and might also bind to poly(A) tails or be involved in protein-protein interactions.

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                  ....*....|....*....|....*....|....*....|....*....
gi 1972263954 118 LFVGNLPNEVKETELKELFSPHGDIAECYL-------SGKGFAFLRLIS 159
Cdd:cd12377     2 IFVYNLAPDADESLLWQLFGPFGAVQNVKIirdfttnKCKGYGFVTMTN 50

RNA recognition motif 2 (RRM2) found in RNA-binding protein MRN1 and similar proteins; This subgroup corresponds to the RRM2 of MRN1, also termed multicopy suppressor of RSC-NHP6 synthetic lethality protein 1, or post-transcriptional regulator of 69 kDa, which is a RNA-binding protein found in yeast. Although its specific biological role remains unclear, MRN1 might be involved in translational regulation. Members in this family contain four copies of conserved RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain).

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                  ....*....|....*....|....*....|....*....|....*....
gi 1972263954 114 GRCR-LFVGNLPNEVKETELKELFSPHGDIaECY--LSGKGFAFLRLIS 159
Cdd:cd12523     1 GASRnVYLGNLPESITEEELREDLEKFGPI-DQIkiVKEKNIAFVHFLS 48

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 1972263954 117 RLFVGNLPNE-VKETELKELFSPHGDIAECYLSgKGFAFLRLISNAA 162
Cdd:cd12342     1 RLFIGNLPTKrVSKEDLFRIFSPYGHLMQIVIK-NAFGFVQFDSPQS 46

RNA recognition motif 1 (RRM1) found in fungal Mei2-like proteins; This subgroup corresponds to the RRM1 of fungal Mei2-like proteins. The Mei2 protein is an essential component of the switch from mitotic to meiotic growth in the fission yeast Schizosaccharomyces pombe. It is an RNA-binding protein that contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). In the nucleus, S. pombe Mei2 stimulates meiosis upon binding a specific non-coding RNA through its C-terminal RRM motif.

                          10        20
                  ....*....|....*....|....*
gi 1972263954 118 LFVGNLPNEVKETELKELFSPHGDI 142
Cdd:cd12525    10 LKVTGVPKDVSTSNLKEIFEKMGDV 34

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.

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                  ....*....|....*....|....*....|....*....|....
gi 1972263954 118 LFVGNLPNEVKETELKELFSPHGDIAECYL-------SGKGFAF 154
Cdd:cd12398     3 VFVGNIPYDATEEQLKEIFSEVGPVVSFRLvtdretgKPKGYGF 46

RNA recognition motif 2 (RRM2) found in TAR DNA-binding protein 43 (TDP-43) and similar proteins; This subfamily corresponds to the RRM2 of TDP-43 (also termed TARDBP), a ubiquitously expressed pathogenic protein whose normal function and abnormal aggregation are directly linked to the genetic disease cystic fibrosis, and two neurodegenerative disorders: frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). TDP-43 binds both DNA and RNA, and has been implicated in transcriptional repression, pre-mRNA splicing and translational regulation. TDP-43 is a dimeric protein with two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal glycine-rich domain. The RRMs are responsible for DNA and RNA binding; they bind to TAR DNA and RNA sequences with UG-repeats. The glycine-rich domain can interact with the hnRNP family proteins to form the hnRNP-rich complex involved in splicing inhibition. It is also essential for the cystic fibrosis transmembrane conductance regulator (CFTR) exon 9-skipping activity.

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                  ....*....|....*....|....*....|....*....|....*....|..
gi 1972263954 116 CRLFVGNLPNEVKETELKELFSPHGDIAECYLSG--KGFAFLRLISNAANKS 165
Cdd:cd12322     1 RKVFVGRCTEDMTEDDLRQYFSQFGEVTDVFIPKpfRAFAFVTFADDEVAQS 52

RNA recognition motif 2 (RRM2) found in Drosophila sex-lethal (SXL) and similar proteins; This subfamily corresponds to the RRM2 of the sex-lethal protein (SXL) which governs sexual differentiation and X chromosome dosage compensation in Drosophila melanogaster. It induces female-specific alternative splicing of the transformer (tra) pre-mRNA by binding to the tra uridine-rich polypyrimidine tract at the non-sex-specific 3' splice site during the sex-determination process. SXL binds also to its own pre-mRNA and promotes female-specific alternative splicing. SXL contains an N-terminal Gly/Asn-rich domain that may be responsible for the protein-protein interaction, and tandem RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), that show high preference to bind single-stranded, uridine-rich target RNA transcripts.

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gi 1972263954 118 LFVGNLPNEVKETELKELFSPHGDIAECYL-----SG--KGFAFLR 156
Cdd:cd12651     5 LYVTNLPRTITEDELDTIFGAYGNIVQKNLlrdklTGrpRGVAFVR 50

RNA recognition motif (RRM) found in U2-associated protein SR140 and similar proteins; This subgroup corresponds to the RRM of SR140 (also termed U2 snRNP-associated SURP motif-containing protein orU2SURP, or 140 kDa Ser/Arg-rich domain protein) which is a putative splicing factor mainly found in higher eukaryotes. Although it is initially identified as one of the 17S U2 snRNP-associated proteins, the molecular and physiological function of SR140 remains unclear. SR140 contains an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a SWAP/SURP domain that is found in a number of pre-mRNA splicing factors in the middle region, and a C-terminal arginine/serine-rich domain (RS domain).

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                  ....*....|....*....|....*.
gi 1972263954 118 LFVGNLPNEVKETELKELFSPHGDIA 143
Cdd:cd12223     4 LYVGNLPPSVTEEVLLREFGRFGPLA 29

RNA recognition motif 1 (RRM1) found in CUGBP Elav-like family member CELF-1, CELF-2, Drosophila melanogaster Bruno protein and similar proteins; This subgroup corresponds to the RRM1 of CELF-1, CELF-2 and Bruno protein. CELF-1 (also termed BRUNOL-2, or CUG-BP1, or EDEN-BP) and CELF-2 (also termed BRUNOL-3, or ETR-3, or CUG-BP2, or NAPOR) belong to the CUGBP1 and ETR-3-like factors (CELF) or BRUNOL (Bruno-like) family of RNA-binding proteins that have been implicated in regulation of pre-mRNA splicing, and control of mRNA translation and deadenylation. CELF-1 is strongly expressed in all adult and fetal tissues tested. The human CELF-1 is a nuclear and cytoplasmic RNA-binding protein that regulates multiple aspects of nuclear and cytoplasmic mRNA processing, with implications for onset of type 1 myotonic dystrophy (DM1), a neuromuscular disease associated with an unstable CUG triplet expansion in the 3'-UTR (3'-untranslated region) of the DMPK (myotonic dystrophy protein kinase) gene; it preferentially targets UGU-rich mRNA elements. It has been shown to bind to a Bruno response element, a cis-element involved in translational control of oskar mRNA in Drosophila, and share sequence similarity to Bruno, the Drosophila protein that mediates this process. The Xenopus homolog embryo deadenylation element-binding protein (EDEN-BP) mediates sequence-specific deadenylation of Eg5 mRNA. It binds specifically to the EDEN motif in the 3'-untranslated regions of maternal mRNAs and targets these mRNAs for deadenylation and translational repression. CELF-1 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 two N-terminal RRMs of EDEN-BP are necessary for the interaction with EDEN as well as a part of the linker region (between RRM2 and RRM3). Oligomerization of EDEN-BP is required for specific mRNA deadenylation and binding. CELF-2 is expressed in all tissues at some level, but highest in brain, heart, and thymus. It has been implicated in the regulation of nuclear and cytoplasmic RNA processing events, including alternative splicing, RNA editing, stability and translation. CELF-2 shares high sequence identity with CELF-1, but shows different binding specificity; it binds preferentially to sequences with UG repeats and UGUU motifs. It has been shown to bind to a Bruno response element, a cis-element involved in translational control of oskar mRNA in Drosophila, and share sequence similarity to Bruno, the Drosophila protein that mediates this process. It also binds to the 3'-UTR of cyclooxygenase-2 messages, affecting both translation and mRNA stability, and binds to apoB mRNA, regulating its C to U editing. CELF-2 also contains three highly conserved RRMs. It binds to RNA via the first two RRMs, which are also important for localization in the cytoplasm. The splicing activation or repression activity of CELF-2 on some specific substrates is mediated by RRM1/RRM2. Both, RRM1 and RRM2 of CELF-2, can activate cardiac troponin T (cTNT) exon 5 inclusion. In addition, CELF-2 possesses a typical arginine and lysine-rich nuclear localization signal (NLS) in the C-terminus, within RRM3. This subgroup also includes Drosophila melanogaster Bruno protein, which plays a central role in regulation of Oskar (Osk) expression in flies. It mediates repression by binding to regulatory Bruno response elements (BREs) in the Osk mRNA 3' UTR. The full-length Bruno protein contains three RRMs, two located in the N-terminal half of the protein and the third near the C-terminus, separated by a linker region.

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gi 1972263954 117 RLFVGNLPNEVKETELKELFSPHGDIAEC 145
Cdd:cd12631     3 KMFVGQIPRSWSEKELRELFEQYGAVYQI 31

RNA recognition motif 6 (RRM6) found in RNA-binding protein 19 (RBM19) and similar proteins; This subgroup corresponds to the RRM6 of RBM19, also termed RNA-binding domain-1 (RBD-1), which is a nucleolar protein conserved in eukaryotes. It is involved in ribosome biogenesis by processing rRNA. In addition, it is essential for preimplantation development. RBM19 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 1972263954 116 CRLFVGNLPNEVKETELKELFSPHGDIAECYLSGK--------GFAFLRLISNAANKS 165
Cdd:cd12571     1 SKILVRNIPFQATVKEVRELFSTFGELKTVRLPKKmggtgqhrGFGFVDFITKQDAKR 58

RNA recognition motif (RRM) found in Pre-mRNA-splicing factor RBM22 and similar proteins; This subgroup corresponds to the RRM of RBM22 (also known as RNA-binding motif protein 22, or Zinc finger CCCH domain-containing protein 16), a newly discovered RNA-binding motif protein which belongs to the SLT11 gene family. SLT11 gene encoding protein (Slt11p) is a splicing factor in yeast, which is required for spliceosome assembly. Slt11p has two distinct biochemical properties: RNA-annealing and RNA-binding activities. RBM22 is the homolog of SLT11 in vertebrate. It has been reported to be involved in pre-splicesome assembly and to interact with the Ca2+-signaling protein ALG-2. It also plays an important role in embryogenesis. RBM22 contains a conserved RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a zinc finger of the unusual type C-x8-C-x5-C-x3-H, and a C-terminus that is unusually rich in the amino acids Gly and Pro, including sequences of tetraprolines.

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                  ....*....|....*....|....*..
gi 1972263954 116 CRLFVGNLPNEVKETELKELFSPHGDI 142
Cdd:cd12224     2 TTLYVGGLGDKITEKDLRDHFYQFGEI 28

RNA recognition motif 1 (RRM1) found in RNA-binding protein Musashi homolog 1 (Musashi-1) and similar proteins; This subgroup corresponds to the RRM1 of Musashi-1. The mammalian MSI1 gene encoding Musashi-1 (also termed Msi1) is a neural RNA-binding protein putatively expressed in central nervous system (CNS) stem cells and neural progenitor cells and associated with asymmetric divisions in neural progenitor cells. Musashi-1 is evolutionarily conserved from invertebrates to vertebrates. It is a homolog of Drosophila Musashi and Xenopus laevis nervous system-specific RNP protein-1 (Nrp-1). Musashi-1 has been implicated in the maintenance of the stem-cell state, differentiation, and tumorigenesis. It translationally regulates the expression of a mammalian numb gene by binding to the 3'-untranslated region of mRNA of Numb, encoding a membrane-associated inhibitor of Notch signaling, and further influences neural development. Moreover, it represses translation by interacting with the poly(A)-binding protein and competes for binding of the eukaryotic initiation factor-4G (eIF-4G). Musashi-1 contains two conserved N-terminal tandem RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), along with other domains of unknown function.

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gi 1972263954 116 CRLFVGNLPNEVKETELKELFSPHGDIAECYL-------SGKGFAFLRLISNAA 162
Cdd:cd12759     1 CKMFIGGLSWQTTQEGLREYFGQFGEVKECLVmrdpltkRSRGFGFVTFMDQAG 54

RNA recognition motif (RRM) found in Tudor domain-containing protein 10 (TDRD10) and similar proteins; TDRD10 is widely expressed and localized both to the nucleus and cytoplasm and may play general roles like regulation of RNA metabolism. It contains a Tudor domain and a RNA recognition motif (RRM).

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                  ....*....|....*....|....*....|....*....|....
gi 1972263954 118 LFVGNLPNEVKETELKELFSPHGD-IAECYLSG-KGFAFLRLIS 159
Cdd:cd21617     2 VYVGNLPLDISEEEILQLFKAFNPvLVKKIRSGfKCFAFVDLGS 45