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 334183229 176 DFGSRMSNISFTDQHVSTYFGNFGPVLSVRIPNQKEQVYGFVSFANAETVTTILDQENPHLIGESPVNVT 245
Cdd:cd12458    1 IYLTFPAESSFTEEDVSTYFSSFGPVQDVRIPYQQKRMFGFVTFANAETVKTILAEGNPHFICDSRVLVK 70

RNA recognition motif (RRM) found in Arabidopsis thaliana zinc finger CCCH domain-containing protein 46 (AtC3H46) and similar proteins; This subfamily corresponds to the RRM domain in AtC3H46, a putative RNA-binding protein that contains an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a CCCH class of zinc finger, typically C-X8-C-X5-C-X3-H. It may possess ribonuclease activity.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 334183229 176 DFGSRMSNISFTDQHVSTYFGNFGPVLSVRIPNQKEQVYGFVSFANAETVTTILDQENPHLIGESPVNVT 245
Cdd:cd12458    1 IYLTFPAESSFTEEDVSTYFSSFGPVQDVRIPYQQKRMFGFVTFANAETVKTILAEGNPHFICDSRVLVK 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.

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                  ....*....|....*....|....*....|....*....|....*....|
gi 334183229  187 TDQHVSTYFGNFGPVLSVRIPNQ---KEQVYGFVSFANAETVTTILDQEN 233
Cdd:pfam00076  11 TEEDLKDLFSKFGPIKSIRLVRDetgRSKGFAFVEFEDEEDAEKAIEALN 60

RNA recognition motif (RRM) found in Arabidopsis thaliana zinc finger CCCH domain-containing protein 46 (AtC3H46) and similar proteins; This subfamily corresponds to the RRM domain in AtC3H46, a putative RNA-binding protein that contains an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a CCCH class of zinc finger, typically C-X8-C-X5-C-X3-H. It may possess ribonuclease activity.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 334183229 176 DFGSRMSNISFTDQHVSTYFGNFGPVLSVRIPNQKEQVYGFVSFANAETVTTILDQENPHLIGESPVNVT 245
Cdd:cd12458    1 IYLTFPAESSFTEEDVSTYFSSFGPVQDVRIPYQQKRMFGFVTFANAETVKTILAEGNPHFICDSRVLVK 70

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 334183229 183 NISF--TDQHVSTYFGNFGPVLSVRIPNQKEQV---YGFVSFANAETVTTILDQENPHLIGESPVNVTAA 247
Cdd:cd12412    9 GIDWdtTEEELREFFSKFGKVKDVKIIKDRAGVskgYGFVTFETQEDAEKIQKWGANLVFKGKKLNVGPA 78

RNA recognition motif 2 (RRM2) found in heterogeneous nuclear ribonucleoprotein hnRNP D0, hnRNP A/B, hnRNP DL and similar proteins; This subfamily corresponds to the RRM2 of hnRNP D0, hnRNP A/B, hnRNP DL and similar proteins. hnRNP D0, a UUAG-specific nuclear RNA binding protein that may be involved in pre-mRNA splicing and telomere elongation. hnRNP A/B is an RNA unwinding protein with a high affinity for G- followed by U-rich regions. It has also been identified as an APOBEC1-binding protein that interacts with apolipoprotein B (apoB) mRNA transcripts around the editing site and thus plays an important role in apoB mRNA editing. hnRNP DL (or hnRNP D-like) is a dual functional protein that possesses DNA- and RNA-binding properties. It has been implicated in mRNA biogenesis at the transcriptional and post-transcriptional levels. All memembers in this family contain two putative RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a glycine- and tyrosine-rich C-terminus.

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gi 334183229 187 TDQHVSTYFGNFGPVLSVRIP--NQKEQVYG--FVSFANAETVTTILDQENpHLIGESPVNVTAA 247
Cdd:cd12329   12 TEEKIREYFGKFGNIVEIELPmdKKTNKRRGfcFITFDSEEPVKKILETQF-HVIGGKKVEVKKA 75

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

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gi 334183229 187 TDQHVSTYFGNFGPVLSVRIPNQKEqvYGFVSFANAETVTTILDQENPHLIGESPV 242
Cdd:cd12346   14 TEEDLRVLFGPFGEIVYVKIPPGKG--CGFVQFVNRASAEAAIQKLQGTPIGGSRI 67

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 334183229  187 TDQHVSTYFGNFGPVLSVRIPNQ---KEQVYGFVSFANAETVTTILDQEN 233
Cdd:pfam00076  11 TEEDLKDLFSKFGPIKSIRLVRDetgRSKGFAFVEFEDEEDAEKAIEALN 60

RNA recognition motif 1 (RRM1) found in TAR DNA-binding protein 43 (TDP-43) and similar proteins; This subfamily corresponds to the RRM1 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 334183229 187 TDQHVSTYFGNFGPVLSVRI----PNQKEQVYGFVSFANAETVTTILDQEnpHLIGE 239
Cdd:cd12321   12 TEQDLKEYFSTFGEVLMVQVkkdpKTGRSKGFGFVRFASYETQVKVLSQR--HMIDG 66

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 334183229 185 SFTDQHVSTYFGNFGPVLSVRI---PNQKEQVYGFVSFANAE 223
Cdd:cd12380   12 DVDDDELKELFEKYGKITSAKVmkdDSGKSKGFGFVNFENHE 53

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 334183229 194 YFGNFGPVLSVRIPNQKeQVYGFVSFANAETVTTILDQEnpHLIGESPVNVTAA 247
Cdd:cd12322   20 YFSQFGEVTDVFIPKPF-RAFAFVTFADDEVAQSLCGED--HIIKGVSVHISNA 70

RNA recognition motif in yeast ribosome biogenesis protein 15 (Nop15p) and similar proteins; This subgroup corresponds to the RRM of Nop15p, also termed nucleolar protein 15, which is encoded by YNL110C from Saccharomyces cerevisiae, and localizes to the nucleoplasm and nucleolus. Nop15p has been identified as a component of a pre-60S particle. It interacts with RNA components of the early pre-60S particles. Furthermore, Nop15p binds directly to a pre-rRNA transcript in vitro and is required for pre-rRNA processing. It functions as a ribosome synthesis factor required for the 5' to 3' exonuclease digestion that generates the 5' end of the major, short form of the 5.8S rRNA as well as for processing of 27SB to 7S pre-rRNA. Nop15p also play a specific role in cell cycle progression. Nop15p contains an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain).

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gi 334183229 186 FTDQHVSTYFGNFGPVLSVRIPNQKE----QVYGFVSFANAETVTTILDQENPHLI 237
Cdd:cd12552   11 FHEKELKKYFAQFGDLKNVRLARSKKtgnsKHYGFLEFVNPEDAMIAQKSMNNYLL 66

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 334183229 183 NISF--TDQHVSTYFGNFGPVLSVRIP---NQKEQVYGFVSFAN 221
Cdd:cd12414    6 NLPFkcTEDDLKKLFSKFGKVLEVTIPkkpDGKLRGFAFVQFTN 49