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).

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gi 2020930328 181 KRLHVSNIPFRFRDPDLRQMFGQFGKILDVEIIFNERGSK 220
Cdd:cd12407     1 KRLHVSNIPFRFRDPDLRQMFGQFGTILDVEIIFNERGSK 40

RNA recognition motif (RRM) found in vertebrate RNA binding protein fox-1 homologs and similar proteins; This subfamily corresponds to the RRM of several tissue-specific alternative splicing isoforms of vertebrate RNA binding protein Fox-1 homologs, which show high sequence similarity to the Caenorhabditis elegans feminizing locus on X (Fox-1) gene encoding Fox-1 protein. RNA binding protein Fox-1 homolog 1 (RBFOX1), also termed ataxin-2-binding protein 1 (A2BP1), or Fox-1 homolog A, or hexaribonucleotide-binding protein 1 (HRNBP1), is predominantly expressed in neurons, skeletal muscle and heart. It regulates alternative splicing of tissue-specific exons by binding to UGCAUG elements. Moreover, RBFOX1 binds to the C-terminus of ataxin-2 and forms an ataxin-2/A2BP1 complex involved in RNA processing. RNA binding protein fox-1 homolog 2 (RBFOX2), also termed Fox-1 homolog B, or hexaribonucleotide-binding protein 2 (HRNBP2), or RNA-binding motif protein 9 (RBM9), or repressor of tamoxifen transcriptional activity, is expressed in ovary, whole embryo, and human embryonic cell lines in addition to neurons and muscle. RBFOX2 activates splicing of neuron-specific exons through binding to downstream UGCAUG elements. RBFOX2 also functions as a repressor of tamoxifen activation of the estrogen receptor. RNA binding protein Fox-1 homolog 3 (RBFOX3 or NeuN or HRNBP3), also termed Fox-1 homolog C, is a nuclear RNA-binding protein that regulates alternative splicing of the RBFOX2 pre-mRNA, producing a message encoding a dominant negative form of the RBFOX2 protein. Its message is detected exclusively in post-mitotic regions of embryonic brain. Like RBFOX1, both RBFOX2 and RBFOX3 bind to the hexanucleotide UGCAUG elements and modulate brain and muscle-specific splicing of exon EIIIB of fibronectin, exon N1 of c-src, and calcitonin/CGRP. Members in this family also harbor one RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

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gi 2020930328 181 KRLHVSNIPFRFRDPDLRQMFGQFGKILDVEIIFNERGSK 220
Cdd:cd12407     1 KRLHVSNIPFRFRDPDLRQMFGQFGTILDVEIIFNERGSK 40

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

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gi 2020930328 181 KRLHVSNIPFRFRDPDLRQMFGQFGKILDVEII 213
Cdd:COG0724     2 MKIYVGNLPYSVTEEDLRELFSEYGEVTSVKLI 34

RNA recognition motif (RRM) found in vertebrate RNA binding protein fox-1 homologs and similar proteins; This subfamily corresponds to the RRM of several tissue-specific alternative splicing isoforms of vertebrate RNA binding protein Fox-1 homologs, which show high sequence similarity to the Caenorhabditis elegans feminizing locus on X (Fox-1) gene encoding Fox-1 protein. RNA binding protein Fox-1 homolog 1 (RBFOX1), also termed ataxin-2-binding protein 1 (A2BP1), or Fox-1 homolog A, or hexaribonucleotide-binding protein 1 (HRNBP1), is predominantly expressed in neurons, skeletal muscle and heart. It regulates alternative splicing of tissue-specific exons by binding to UGCAUG elements. Moreover, RBFOX1 binds to the C-terminus of ataxin-2 and forms an ataxin-2/A2BP1 complex involved in RNA processing. RNA binding protein fox-1 homolog 2 (RBFOX2), also termed Fox-1 homolog B, or hexaribonucleotide-binding protein 2 (HRNBP2), or RNA-binding motif protein 9 (RBM9), or repressor of tamoxifen transcriptional activity, is expressed in ovary, whole embryo, and human embryonic cell lines in addition to neurons and muscle. RBFOX2 activates splicing of neuron-specific exons through binding to downstream UGCAUG elements. RBFOX2 also functions as a repressor of tamoxifen activation of the estrogen receptor. RNA binding protein Fox-1 homolog 3 (RBFOX3 or NeuN or HRNBP3), also termed Fox-1 homolog C, is a nuclear RNA-binding protein that regulates alternative splicing of the RBFOX2 pre-mRNA, producing a message encoding a dominant negative form of the RBFOX2 protein. Its message is detected exclusively in post-mitotic regions of embryonic brain. Like RBFOX1, both RBFOX2 and RBFOX3 bind to the hexanucleotide UGCAUG elements and modulate brain and muscle-specific splicing of exon EIIIB of fibronectin, exon N1 of c-src, and calcitonin/CGRP. Members in this family also harbor one RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

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gi 2020930328 181 KRLHVSNIPFRFRDPDLRQMFGQFGKILDVEIIFNERGSK 220
Cdd:cd12407     1 KRLHVSNIPFRFRDPDLRQMFGQFGTILDVEIIFNERGSK 40

RNA recognition motif;

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gi 2020930328  182 RLHVSNIPFRFRDPDLRQMFGQFGKILDVEIIFNE 216
Cdd:smart00360   1 TLFVGNLPPDTTEEELRELFSKFGKVESVRLVRDK 35

RNA recognition motif (RRM) found in Zinc finger CCHC-type and RNA-binding motif-containing protein 1 (ZCRB1) and similar proteins; This subfamily corresponds to the RRM of ZCRB1, also termed MADP-1, or U11/U12 small nuclear ribonucleoprotein 31 kDa protein (U11/U12 snRNP 31 or U11/U12-31K), a novel multi-functional nuclear factor, which may be involved in morphine dependence, cold/heat stress, and hepatocarcinoma. It is located in the nucleoplasm, but outside the nucleolus. ZCRB1 is one of the components of U11/U12 snRNPs that bind to U12-type pre-mRNAs and form a di-snRNP complex, simultaneously recognizing the 5' splice site and branchpoint sequence. ZCRB1 is characterized by an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a CCHC-type Zinc finger motif. In addition, it contains core nucleocapsid motifs, and Lys- and Glu-rich domains.

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gi 2020930328 177 KSTpkrLHVSNIPFRFRDPDLRQMFGQFGKILDVEII---------------FNERGSKVNnaTARVMTNKKM 234
Cdd:cd12393     1 KST---VYVSNLPFSLTNNDLHQIFSKYGKVVKVTILkdketrkskgvafvlFLDRESAHN--AVRAMNNKEL 68

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 2020930328 180 PKRLHVSNIPFRFRDPDLRQMFGQFGKILDVEII 213
Cdd:cd12412     2 PNRIFVGGIDWDTTEEELREFFSKFGKVKDVKII 35

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 2020930328 182 RLHVSNIPFRFRDPDLRQMFGQFGKILDVEIIFN 215
Cdd:cd21608     1 KLYVGNLSWDTTEDDLRDLFSEFGEVESAKVITD 34

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.

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gi 2020930328 185 VSNIPFRFRDPDLRQMFGQFGKILDVEIIFNERGS 219
Cdd:pfam00076   3 VGNLPPDTTEEDLKDLFSKFGPIKSIRLVRDETGR 37

RNA recognition motif 3 (RRM3) found in Saccharomyces cerevisiae protein HRB1, G-strand-binding protein 2 (GBP2) and similar proteins; The family includes Saccharomyces cerevisiae protein HRB1 (also called protein TOM34) and GBP2, both of which are SR-like mRNA-binding proteins which shuttle from the nucleus to the cytoplasm when bound to the mature mRNA molecules. They act as quality control factors for spliced mRNAs. GBP2, also called RAP1 localization factor 6, is a single-strand telomeric DNA-binding protein that binds single-stranded telomeric sequences of the type (TG[1-3])n in vitro. It also binds to RNA. GBP2 influences the localization of RAP1 in the nuclei and plays a role in modulating telomere length. Members in this family contain three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the third RRM motif.

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gi 2020930328 183 LHVSNIPFRFRDPDLRQMFGQFGKILDVEIIFNERGSKVNNA 224
Cdd:cd21607     5 IYCSNLPLSTAESDLYDLFETIGKVNNAELKYDETGDPTGSA 46

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

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gi 2020930328 183 LHVSNIPFRFRDPDLRQMFGQFGKILdveiifnergskvnnaTARVMTNKK 233
Cdd:cd12362     1 LFVYHLPNEFTDQDLYQLFAPFGNVV----------------SAKVFVDKN 35

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.

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gi 2020930328 181 KRLHVSNIPFRFRDPDLRQMFGQFGKILDVEIIFNERGSK 220
Cdd:cd12566     3 GRLFLRNLPYSTKEDDLQKLFSKFGEVSEVHVPIDKKTKK 42

RNA recognition motif 1 (RRM1) found in yeast multiple RNA-binding domain-containing protein 1 (MRD1) and similar proteins; This subgroup corresponds to the RRM1 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). MRD1 is essential for the initial processing at the A0-A2 cleavage sites in the 35 S pre-rRNA. It 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.

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gi 2020930328 182 RLHVSNIPFRFRDPDLRQMFGQFGKILDVEIIFNERG 218
Cdd:cd12565     2 RIIVKNLPKYVTEKRLKEHFSKKGEITDVKVMRTKDG 38

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.

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gi 2020930328 182 RLHVSNIPFRFRDPDLRQMFGQFGKILDVEIIfNERGS 219
Cdd:cd12598     1 RIYVGNLPSDVREKDLEDLFYKYGRIRDIELK-NRRGL 37