RNA recognition motif (RRM) found in yeast RNA-binding protein PIN4, fission yeast RNA-binding post-transcriptional regulators cip1, cip2 and similar proteins; This subfamily corresponds to the RRM in PIN4, also termed psi inducibility protein 4 or modifier of damage tolerance Mdt1, a novel phosphothreonine (pThr)-containing protein that specifically interacts with the pThr-binding site of the Rad53 FHA1 domain. It is encoded by gene MDT1 (YBL051C) from yeast Saccharomyces cerevisiae. PIN4 is involved in normal G2/M cell cycle progression in the absence of DNA damage and functions as a novel target of checkpoint-dependent cell cycle arrest pathways. It contains an N-terminal RRM, a nuclear localization signal, a coiled coil, and a total of 15 SQ/TQ motifs. cip1 (Csx1-interacting protein 1) and cip2 (Csx1-interacting protein 2) are novel cytoplasmic RRM-containing proteins that counteract Csx1 function during oxidative stress. They are not essential for viability in fission yeast Schizosaccharomyces pombe. Both cip1 and cip2 contain one RRM. Like PIN4, Cip2 also possesses an R3H motif that may function in sequence-specific binding to single-stranded nucleic acids.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 19113563 201 PTAIVVKNIPFSLEKDTLLDHFKQLGIPRPYAFNYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRVEWKR 279
Cdd:cd12253   1 PTAIVIKNIPFSLRKEQLLDIIEDLGIPLPYAFNYHFDNGVFRGLAFANFRSPEEAQTVVEALNGYEISGRRLRVEYKR 79

RNA recognition motif (RRM) found in yeast RNA-binding protein PIN4, fission yeast RNA-binding post-transcriptional regulators cip1, cip2 and similar proteins; This subfamily corresponds to the RRM in PIN4, also termed psi inducibility protein 4 or modifier of damage tolerance Mdt1, a novel phosphothreonine (pThr)-containing protein that specifically interacts with the pThr-binding site of the Rad53 FHA1 domain. It is encoded by gene MDT1 (YBL051C) from yeast Saccharomyces cerevisiae. PIN4 is involved in normal G2/M cell cycle progression in the absence of DNA damage and functions as a novel target of checkpoint-dependent cell cycle arrest pathways. It contains an N-terminal RRM, a nuclear localization signal, a coiled coil, and a total of 15 SQ/TQ motifs. cip1 (Csx1-interacting protein 1) and cip2 (Csx1-interacting protein 2) are novel cytoplasmic RRM-containing proteins that counteract Csx1 function during oxidative stress. They are not essential for viability in fission yeast Schizosaccharomyces pombe. Both cip1 and cip2 contain one RRM. Like PIN4, Cip2 also possesses an R3H motif that may function in sequence-specific binding to single-stranded nucleic acids.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 19113563 201 PTAIVVKNIPFSLEKDTLLDHFKQLGIPRPYAFNYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRVEWKR 279
Cdd:cd12253   1 PTAIVIKNIPFSLRKEQLLDIIEDLGIPLPYAFNYHFDNGVFRGLAFANFRSPEEAQTVVEALNGYEISGRRLRVEYKR 79

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

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 19113563   204 IVVKNIPFSLEKDTLLDHFKQLG------IPRPyafnyhyDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLR 274
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGpiksirLVRD-------ETGRSKGFAFVEFEDEEDAEKAIEALNGKELGGRELK 70

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

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19113563   202 TAIVVKNIPFSLEKDTLLDHFKQLGIPRPYAFNYHyDNGIFRGLAFANFYRPEEAQVVVQTLNGYEI----NGRRLRVew 277
Cdd:TIGR01628 179 TNLYVKNLDPSVNEDKLRELFAKFGEITSAAVMKD-GSGRSRGFAFVNFEKHEDAAKAVEEMNGKKIglakEGKKLYV-- 255

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|....*..
gi 19113563   278 KRQLPAAEREKVEKAKKRQ-AEERRRKQQY-----KMFEVSFTDQGL 318
Cdd:TIGR01628 256 GRAQKRAEREAELRRKFEElQQERKMKAQGvnlyvKNLDDTVTDEKL 302

RNA recognition motif (RRM) found in yeast RNA-binding protein PIN4, fission yeast RNA-binding post-transcriptional regulators cip1, cip2 and similar proteins; This subfamily corresponds to the RRM in PIN4, also termed psi inducibility protein 4 or modifier of damage tolerance Mdt1, a novel phosphothreonine (pThr)-containing protein that specifically interacts with the pThr-binding site of the Rad53 FHA1 domain. It is encoded by gene MDT1 (YBL051C) from yeast Saccharomyces cerevisiae. PIN4 is involved in normal G2/M cell cycle progression in the absence of DNA damage and functions as a novel target of checkpoint-dependent cell cycle arrest pathways. It contains an N-terminal RRM, a nuclear localization signal, a coiled coil, and a total of 15 SQ/TQ motifs. cip1 (Csx1-interacting protein 1) and cip2 (Csx1-interacting protein 2) are novel cytoplasmic RRM-containing proteins that counteract Csx1 function during oxidative stress. They are not essential for viability in fission yeast Schizosaccharomyces pombe. Both cip1 and cip2 contain one RRM. Like PIN4, Cip2 also possesses an R3H motif that may function in sequence-specific binding to single-stranded nucleic acids.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 19113563 201 PTAIVVKNIPFSLEKDTLLDHFKQLGIPRPYAFNYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRVEWKR 279
Cdd:cd12253   1 PTAIVIKNIPFSLRKEQLLDIIEDLGIPLPYAFNYHFDNGVFRGLAFANFRSPEEAQTVVEALNGYEISGRRLRVEYKR 79

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLGIPRpYAFNYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRVE 276
Cdd:cd00590   1 LFVGNLPPDTTEEDLRELFSKFGEVV-SVRIVRDRDGKSKGFAFVEFESPEDAEKALEALNGTELGGRPLKVS 72

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

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 19113563   204 IVVKNIPFSLEKDTLLDHFKQLG------IPRPyafnyhyDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLR 274
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGpiksirLVRD-------ETGRSKGFAFVEFEDEEDAEKAIEALNGKELGGRELK 70

RNA recognition motif 1 (RRM1) found in chloroplastic plastid-specific 30S ribosomal protein 2 (PSRP-2) and similar proteins; PSRP-2, also called chloroplastic 30S ribosomal protein 2, or chloroplastic small ribosomal subunit protein cS22, is a component of the chloroplast ribosome (chloro-ribosome), a dedicated translation machinery responsible for the synthesis of chloroplast genome-encoded proteins, including proteins of the transcription and translation machinery and components of the photosynthetic apparatus. It binds single strand DNA (ssDNA) and RNA in vitro. It exhibits RNA chaperone activity and regulates negatively resistance responses to abiotic stresses during seed germination (e.g. salt, dehydration, and low temperature) and seedling growth (e.g. salt). The family also includes Nicotiana sylvestris chloroplastic 33 kDa ribonucleoprotein (NsCP33) and Arabidopsis thaliana chloroplastic 31 kDa ribonucleoprotein (AtCP31A). 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. 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 first RRM motif.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLGIPRPYAFNYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd21609   2 LYVGNIPRNVTSEELAKIFEEAGTVEIAEVMYDRYTGRSRGFGFVTMGSVEDAKAAIEKLNGTEVGGREIKV 73

RNA recognition motif 1 (RRM1) found in Schizosaccharomyces pombe mRNA export factor Crp79 and similar proteins; Crp79, also called meiotic expression up-regulated protein 5 (Mug5), or polyadenylate-binding protein crp79, or PABP, or poly(A)-binding protein, is an auxiliary mRNA export factor that binds the poly(A) tail of mRNA and is involved in the export of mRNA from the nucleus to the cytoplasm. 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 first RRM motif.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 19113563 203 AIVVKNIPFSLEKDTLLDHFKQLG----IPRPYAFNYHYDNGifRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd21619   3 TIYVGNIDMTINEDALEKIFSRYGqvesVRRPPIHTDKADRT--TGFGFIKYTDAESAERAMQQADGILLGRRRLVV 77

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLG-------IprpyafnYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd21608   2 LYVGNLSWDTTEDDLRDLFSEFGevesakvI-------TDRETGRSRGFGFVTFSTAEAAEAAIDALNGKELDGRSIVV 73

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

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLG------IPRpyafnyHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRVEw 277
Cdd:COG0724   4 IYVGNLPYSVTEEDLRELFSEYGevtsvkLIT------DRETGRSRGFGFVEMPDDEEAQAAIEALNGAELMGRTLKVN- 76

                        90
                ....*....|.
gi 19113563 278 krqlPAAEREK 288
Cdd:COG0724  77 ----EARPREE 83

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLGipRPYAFNYHYD-NGIFRGLAFANFYRPEEAQVVVQTLNGYEI-NGRRLRVE 276
Cdd:cd12249   4 VFVGKIPRDVFEDELVPLFEKCG--KIYELRLMMDfSGLNRGYAFVTYTNKEAAQRAVKTLNNYEIrPGKLLGVC 76

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

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19113563 202 TAIVVKNIPFSLEKDTLLDHFKQLG------IPRPYafnyhydNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd12320   1 TKLIVKNVPFEATRKEIRELFSPFGqlksvrLPKKF-------DGSHRGFAFVEFVTKQEAQNAMEALKSTHLYGRHLVL 73

                ..
gi 19113563 276 EW 277
Cdd:cd12320  74 EY 75

RNA recognition motif (RRM) found in serine/arginine-rich splicing factor SRSF2, SRSF8 and similar proteins; This subfamily corresponds to the RRM of SRSF2 and SRSF8. SRSF2, also termed protein PR264, or splicing component, 35 kDa (splicing factor SC35 or SC-35), is a prototypical SR protein that plays important roles in the alternative splicing of pre-mRNA. It is also involved in transcription elongation by directly or indirectly mediating the recruitment of elongation factors to the C-terminal domain of polymerase II. SRSF2 is exclusively localized in the nucleus and is restricted to nuclear processes. It contains a single N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), followed by a C-terminal RS domain rich in serine-arginine dipeptides. The RRM is responsible for the specific recognition of 5'-SSNG-3' (S=C/G) RNA. In the regulation of alternative splicing events, it specifically binds to cis-regulatory elements on the pre-mRNA. The RS domain modulates SRSF2 activity through phosphorylation, directly contacts RNA, and promotes protein-protein interactions with the spliceosome. SRSF8, also termed SRP46 or SFRS2B, is a novel mammalian SR splicing factor encoded by a PR264/SC35 functional retropseudogene. SRSF8 is localized in the nucleus and does not display the same activity as PR264/SC35. It functions as an essential splicing factor in complementing a HeLa cell S100 extract deficient in SR proteins. Like SRSF2, SRSF8 contains a single N-terminal RRM and a C-terminal RS domain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 19113563 206 VKNIPFSLEKDTLLDHFKQLG------IPR-PYAFNYhydngifRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd12311   3 VDNLTYRTTPDDLRRVFEKYGevgdvyIPRdRYTRES-------RGFAFVRFYDKRDAEDAIDAMDGAELDGRELRV 72

RNA recognition motif 1 (RRM1) found in heterogeneous nuclear ribonucleoprotein M (hnRNP M) and similar proteins; This subfamily corresponds to the RRM1 of heterogeneous nuclear ribonucleoprotein M (hnRNP M), myelin expression factor 2 (MEF-2 or MyEF-2 or MST156) and similar proteins. hnRNP M is pre-mRNA binding protein that may play an important role in the pre-mRNA processing. It also preferentially binds to poly(G) and poly(U) RNA homopolymers. Moreover, hnRNP M is able to interact with early spliceosomes, further influencing splicing patterns of specific pre-mRNAs. hnRNP M functions as the receptor of carcinoembryonic antigen (CEA) that contains the penta-peptide sequence PELPK signaling motif. In addition, hnRNP M and another splicing factor Nova-1 work together as dopamine D2 receptor (D2R) pre-mRNA-binding proteins. They regulate alternative splicing of D2R pre-mRNA in an antagonistic manner. hnRNP M contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and an unusual hexapeptide-repeat region rich in methionine and arginine residues (MR repeat motif). MEF-2 is a sequence-specific single-stranded DNA (ssDNA) binding protein that binds specifically to ssDNA derived from the proximal (MB1) element of the myelin basic protein (MBP) promoter and represses transcription of the MBP gene. MEF-2 shows high sequence homology with hnRNP M. It also contains three RRMs, which may be responsible for its ssDNA binding activity.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLGIPRPYAFNYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd12385   2 VFISNIPYDYKWQDLKDLFREKVGEVTYVELFKDENGKSRGCGIVEFKDLESVQKALETMNRYELKGRKLVV 73

RNA recognition motif 5 (RRM5) found in yeast multiple RNA-binding domain-containing protein 1 (MRD1) and similar proteins; This subgroup corresponds to the RRM5 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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 19113563 202 TAIVVKNIPFSLEKDTLLDHFKQLGIPRPYAFNYHYDNGIfRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRVEW 277
Cdd:cd12570   1 TKILVKNLPFEATKKDVRTLFSSYGQLKSVRVPKKFDQSA-RGFAFVEFSTAKEALNAMNALKDTHLLGRRLVLQY 75

RNA recognition motif 3 (RRM3) found in Saccharomyces cerevisiae protein PES4, protein MIP6 and similar proteins; The family includes PES4 (also called DNA polymerase epsilon suppressor 4) and MIP6 (also called MEX67-interacting protein 6), both of which are predicted RNA binding proteins that may act as regulators of late translation, protection, and mRNA localization. MIP6 acts as a novel factor for nuclear mRNA export, binds to both poly(A)+ RNA and nuclear pores. It interacts with MEX67. Members in this family contain four RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the third RRM motif.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 19113563 203 AIVVKNIPFSLEKDTLLDHFKQLG------IPRPYAFNYHYdngifrglAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd21603   2 AIFVKNLPLDTNNDEILDFFSKVGpiksvfTSPKYKYNSLW--------AFVTYKKGSDTEKAIKLLNGTLFKGRTIEV 72

RNA recognition motif 1 (RRM1) found in Drosophila sex-lethal (SXL) and similar proteins; This subfamily corresponds to the RRM1 of 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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19113563 202 TAIVVKNIPFSLEKDTLLDHFKQLG------IPRPYAFNYHYdngifrGLAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd12649   1 TNLIVNYLPQDLTDREFRALFRAIGpvntckIVRDKKTGYSY------GFGFVDFTSEEDAQRAIKTLNGLQLQNKRLKV 74

                ....
gi 19113563 276 EWKR 279
Cdd:cd12649  75 AYAR 78

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19113563 206 VKNIPFSLEKDTLLDHFKQLGIPRPYAFnYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd12392   7 VKGLPFSCTKEELEELFKQHGTVKDVRL-VTYRNGKPKGLAYVEYENEADASQAVLKTDGTEIKDHTISV 75

RNA recognition motif 3 (RRM3) found in vertebrate myelin expression factor 2 (MEF-2); This subgroup corresponds to the RRM3 of MEF-2, also termed MyEF-2 or MST156, a sequence-specific single-stranded DNA (ssDNA) binding protein that binds specifically to ssDNA derived from the proximal (MB1) element of the myelin basic protein (MBP) promoter and represses transcription of the MBP gene. MEF-2 contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), which may be responsible for its ssDNA binding activity.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLGipRPYAFNYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRVEWKR 279
Cdd:cd12662   2 IFVRNLPFDLTWQKLKEKFSQCG--HVMFAEIKMENGKSKGCGTVRFDSPESAEKACRLMNGIKISGREIDVRLDR 75

RNA recognition motif 3 (RRM3) found in vertebrate heterogeneous nuclear ribonucleoprotein M (hnRNP M); This subgroup corresponds to the RRM3 of hnRNP M, a pre-mRNA binding protein that may play an important role in the pre-mRNA processing. It also preferentially binds to poly(G) and poly(U) RNA homopolymers. Moreover, hnRNP M is able to interact with early spliceosomes, further influencing splicing patterns of specific pre-mRNAs. hnRNP M functions as the receptor of carcinoembryonic antigen (CEA) that contains the penta-peptide sequence PELPK signaling motif. In addition, hnRNP M and another splicing factor Nova-1 work together as dopamine D2 receptor (D2R) pre-mRNA-binding proteins. They regulate alternative splicing of D2R pre-mRNA in an antagonistic manner. hnRNP M contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and an unusual hexapeptide-repeat region rich in methionine and arginine residues (MR repeat motif).

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLGIPRpYAfNYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRVEWKR 279
Cdd:cd12661   2 IFVRNLPFDFTWKMLKDKFNECGHVL-YA-DIKMENGKSKGCGVVRFESPEVAERACRMMNGIKLNGREIDVRIDR 75

RNA recognition motif (RRM) found in eukaryotic translation initiation factor 4B (eIF-4B) and similar proteins; This subfamily corresponds to the RRM of eIF-4B, a multi-domain RNA-binding protein that has been primarily implicated in promoting the binding of 40S ribosomal subunits to mRNA during translation initiation. It contains two RNA-binding domains; the N-terminal well-conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), binds the 18S rRNA of the 40S ribosomal subunit and the C-terminal basic domain (BD), including two arginine-rich motifs (ARMs), binds mRNA during initiation, and is primarily responsible for the stimulation of the helicase activity of eIF-4A. eIF-4B also contains a DRYG domain (a region rich in Asp, Arg, Tyr, and Gly amino acids) in the middle, which is responsible for both, self-association of eIF-4B and binding to the p170 subunit of eIF3. Additional research indicates that eIF-4B can interact with the poly(A) binding protein (PABP) in mammalian cells, which can stimulate both, the eIF-4B-mediated activation of the helicase activity of eIF-4A and binding of poly(A) by PABP. eIF-4B has also been shown to interact specifically with the internal ribosome entry sites (IRES) of several picornaviruses which facilitate cap-independent translation initiation.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 19113563 206 VKNIPFSLEKDTLLDHFKQLGI-----PRPyafnyhYDNGIFRGLAFANFyrpEEAQVVVQ--TLNGYEINGRRLRVE 276
Cdd:cd12402   7 LGNLPYDVTEDDIEDFFRGLNIssvrlPRE------NGPGRLRGFGYVEF---EDRESLIQalSLNEESLKNRRIRVD 75

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLG-IPRPY-AFNYhyDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRVEW 277
Cdd:cd12408   2 IRVTNLSEDATEEDLRELFRPFGpISRVYlAKDK--ETGQSKGFAFVTFETREDAERAIEKLNGFGYDNLILSVEW 75

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 19113563 202 TAIVVKNIPFSLEKDTLLDHFKQLGIPRPYAFNYHYDnGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRVE 276
Cdd:cd12565   1 SRIIVKNLPKYVTEKRLKEHFSKKGEITDVKVMRTKD-GKSRRFGFIGFKSEEEAQKAVKYFNKTFIDTSKISVE 74

RNA recognition motif 1 (RRM1) found in the Hu proteins family, Drosophila sex-lethal (SXL), and similar proteins; This subfamily corresponds to the RRM1 of Hu proteins and SXL. The Hu proteins family represents 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 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. This family also includes the sex-lethal protein (SXL) from Drosophila melanogaster. SXL governs sexual differentiation and X chromosome dosage compensation in flies. 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 to its own pre-mRNA and promotes female-specific alternative splicing. It contains an N-terminal Gly/Asn-rich domain that may be responsible for the protein-protein interaction, and tandem RRMs that show high preference to bind single-stranded, uridine-rich target RNA transcripts.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLGIPRPYAFNYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd12375   2 LIVNYLPQSMTQEELRSLFGAIGPIESCKLVRDKITGQSLGYGFVNYRDPNDARKAINTLNGLDLENKRLKV 73

RNA recognition motif (RRM) found in the FET family of RNA-binding proteins; This subfamily corresponds to the RRM of FET (previously TET) (FUS/TLS, EWS, TAF15) family of RNA-binding proteins. This ubiquitously expressed family of similarly structured proteins predominantly localizing to the nuclear, includes FUS (also known as TLS or Pigpen or hnRNP P2), EWS (also known as EWSR1), TAF15 (also known as hTAFII68 or TAF2N or RPB56), and Drosophila Cabeza (also known as SARFH). The corresponding coding genes of these proteins are involved in deleterious genomic rearrangements with transcription factor genes in a variety of human sarcomas and acute leukemias. All FET proteins interact with each other and are therefore likely to be part of the very same protein complexes, which suggests a general bridging role for FET proteins coupling RNA transcription, processing, transport, and DNA repair. The FET proteins contain multiple copies of a degenerate hexapeptide repeat motif at the N-terminus. The C-terminal region consists of a conserved nuclear import and retention signal (C-NLS), a putative zinc-finger domain, and a conserved RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), which is flanked by 3 arginine-glycine-glycine (RGG) boxes. FUS and EWS might have similar sequence specificity; both bind preferentially to GGUG-containing RNAs. FUS has also been shown to bind strongly to human telomeric RNA and to small low-copy-number RNAs tethered to the promoter of cyclin D1. To date, nothing is known about the RNA binding specificity of TAF15.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLGI------PRPYAFNYHYDN--GIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd12280   1 IFVSGLPPDVTIDELADLFGQIGIikrykdTWPPKIKIYTDKetGKPKGEATLTYEDPSAAKAAIEWFNGKEFRGNKIKV 80

                .
gi 19113563 276 E 276
Cdd:cd12280  81 S 81

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).

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19113563 202 TAIVVKNIPFSLEKDTLLDHFKQLG------IPRPYAfnyhyDNGIFRGLAFANFYRPEEAQVVVQTL-NGYEINGRRLR 274
Cdd:cd12571   1 SKILVRNIPFQATVKEVRELFSTFGelktvrLPKKMG-----GTGQHRGFGFVDFITKQDAKRAFDALcHSTHLYGRRLV 75

                ...
gi 19113563 275 VEW 277
Cdd:cd12571  76 LEW 78

RNA recognition motif (RRM) found in pre-mRNA cleavage factor Im 68 kDa subunit (CFIm68 or CPSF6), pre-mRNA cleavage factor Im 59 kDa subunit (CFIm59 or CPSF7), and similar proteins; This subfamily corresponds to the RRM of cleavage factor Im (CFIm) subunits. Cleavage factor Im (CFIm) is a highly conserved component of the eukaryotic mRNA 3' processing machinery that functions in UGUA-mediated poly(A) site recognition, the regulation of alternative poly(A) site selection, mRNA export, and mRNA splicing. It is a complex composed of a small 25 kDa (CFIm25) subunit and a larger 59/68/72 kDa subunit. Two separate genes, CPSF6 and CPSF7, code for two isoforms of the large subunit, CFIm68 and CFIm59. Structurally related CFIm68 and CFIm59, also termed cleavage and polyadenylation specificity factor subunit 6 (CPSF7), or cleavage and polyadenylation specificity factor 59 kDa subunit (CPSF59), are functionally redundant. Both contains an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a central proline-rich region, and a C-terminal RS-like domain. Their N-terminal RRM mediates the interaction with CFIm25, and also serves to enhance RNA binding and facilitate RNA looping.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 19113563 233 FNYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRVE 276
Cdd:cd12372  32 FFEHKANGKSKGYAYVEFASPAAAAAVKEKLEKREFNGRPCVVT 75

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLGIPRPYAFNYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRVE 276
Cdd:cd12397   1 LFVGNLSFETTEEDLRKHFAPAGKIRKVRMATFEDSGKCKGFAFVDFKEIESATNAVKGPINHSLNGRDLRVE 73

heterogeneous nuclear ribonucleoprotein R, Q family; Sequences in this subfamily include the human heterogeneous nuclear ribonucleoproteins (hnRNP) R, Q, and APOBEC-1 complementation factor (aka APOBEC-1 stimulating protein). These proteins contain three RNA recognition domains (rrm: pfam00076) and a somewhat variable C-terminal domain.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19113563   195 PGEDTIP----TAIVVKNIPFSLEKDTLLDHFKQLGipRPYAFNYHYD-NGIFRGLAFANFYRPEEAQVVVQTLNGYEI- 268
Cdd:TIGR01648  48 PGWSGVQpgrgCEVFVGKIPRDLYEDELVPLFEKAG--PIYELRLMMDfSGQNRGYAFVTFCGKEEAKEAVKLLNNYEIr 125

                  ....*..
gi 19113563   269 NGRRLRV 275
Cdd:TIGR01648 126 PGRLLGV 132

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19113563 206 VKNIPFSLEKDTLLDHFKQLGIPRPYAFNYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd12284   3 VGSLHFNITEDMLRGIFEPFGKIEFVQLQKDPETGRSKGYGFIQFRDAEDAKKALEQLNGFELAGRPMKV 72

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

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLGI---------PRPYAFnyhydngifrglAFANFYRPEEAQVVVQTLNGYEINGRRLR 274
Cdd:cd12599   2 VYVGNLPMDIREREVEDLFSKYGPvvsidlkipPRPPAY------------AFVEFEDARDAEDAIRGRDGYDFDGHRLR 69

                ..
gi 19113563 275 VE 276
Cdd:cd12599  70 VE 71

RNA recognition motif 1 (RRM1) found in vertebrate RNA-binding protein 46 (RBM46); This subgroup corresponds to the RRM1 of RBM46, also termed cancer/testis antigen 68 (CT68), a putative RNA-binding protein that shows high sequence homology with heterogeneous nuclear ribonucleoprotein R (hnRNP R) and heterogeneous nuclear ribonucleoprotein Q (hnRNP Q). Its biological function remains unclear. Like hnRNP R and hnRNP Q, RBM46 contains two well-defined and one degenerated RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLGipRPYAFNYHYD-NGIFRGLAFANFYRPEEAQVVVQTLNGYEI 268
Cdd:cd12484   4 VFVGKIPRDMYEDELVPVFERAG--KIYEFRLMMEfSGENRGYAFVMYTTKEEAQLAIKMLNNYEI 67

RNA recognition motif 4 (RRM4) found in type I polyadenylate-binding proteins; This subfamily corresponds to the RRM4 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 theThe CD corresponds to the RRM. 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. Moreover, 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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 19113563 206 VKNIPFSLEKDTLLDHFKQLG-IPRpyAFNYHYDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd12381   6 VKNLDDTIDDEKLREEFSPFGtITS--AKVMTDEGGRSKGFGFVCFSSPEEATKAVTEMNGRIIGGKPLYV 74

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

                        10        20        30
                ....*....|....*....|....*....|....*...
gi 19113563 238 DNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRV 275
Cdd:cd12390  38 GNGVPRGFAFVEFASAEDAEEAQQLLNGHDLQGSPIRV 75

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 19113563 202 TAIVVKNIPFSLEKDTLLDHFKQLGIPRPYAFNYHYDNGIFR---GLAFANFYRPEEAQVVVQTLNGYEINGRRL 273
Cdd:cd12318   1 TTLFVKNLNFKTTEEALKKHFEKCGPIRSVTIAKKKDPKGPLlsmGYGFVEFKSPEAAQKALKQLQGTVLDGHAL 75

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLGIPRPYAFNYHyDNGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRLRVEWKR 279
Cdd:cd21607   5 IYCSNLPLSTAESDLYDLFETIGKVNNAELKYD-ETGDPTGSAVVEYENLDDADVCISKLNNYNYGGCDLKISYAK 79

RNA recognition motif 1 (RRM1) found in vertebrate RNA-binding protein 47 (RBM47); This subgroup corresponds to the RRM1 of RBM47, a putative RNA-binding protein that shows high sequence homology with heterogeneous nuclear ribonucleoprotein R (hnRNP R) and heterogeneous nuclear ribonucleoprotein Q (hnRNP Q). Its biological function remains unclear. Like hnRNP R and hnRNP Q, RBM47 contains two well-defined and one degenerated RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 19113563 204 IVVKNIPFSLEKDTLLDHFKQLGipRPYAFNYHYD-NGIFRGLAFANFYRPEEAQVVVQTLNGYEINGRRL 273
Cdd:cd12485   4 VFVGKIPRDVYEDELVPVFESVG--RIYEMRLMMDfDGKNRGYAFVMYTQKHEAKRAVRELNNYEIRPGRL 72

RNA recognition motif (RRM) found in fission yeast pre-mRNA-splicing factor Srp1p, Arabidopsis thaliana arginine/serine-rich-splicing factor RSp31 and similar proteins; This subfamily corresponds to the RRM of Srp1p and RRM2 of plant SR splicing factors. Srp1p is encoded by gene srp1 from fission yeast Schizosaccharomyces pombe. It plays a role in the pre-mRNA splicing process, but is not essential for growth. Srp1p is closely related to the SR protein family found in Metazoa. It contains an N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a glycine hinge and a RS domain in the middle, and a C-terminal domain. The family also includes a novel group of arginine/serine (RS) or serine/arginine (SR) splicing factors existing in plants, such as A. thaliana RSp31, RSp35, RSp41 and similar proteins. Like vertebrate RS splicing factors, these proteins function as plant splicing factors and play crucial roles in constitutive and alternative splicing in plants. They all contain two RRMs at their N-terminus and an RS domain at their C-terminus.

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gi 19113563 221 HFKQLG------IPRPYAFnyhydngifrglafANFYRPEEAQVVVQTLNGYEINGRRLRVEWKR 279
Cdd:cd12233  20 LFEPFGplvrcdIRKTFAF--------------VEFEDSEDATKALEALHGSRIDGSVLTVEFVK 70