RNA recognition motif 2 (RRM2) found in tRNA selenocysteine-associated protein 1 (SECp43) and similar proteins; This subfamily corresponds to the RRM2 in tRNA selenocysteine-associated protein 1 (SECp43), yeast negative growth regulatory protein NGR1 (RBP1), yeast protein NAM8, and similar proteins. SECp43 is an RNA-binding protein associated specifically with eukaryotic selenocysteine tRNA [tRNA(Sec)]. It may play an adaptor role in the mechanism of selenocysteine insertion. SECp43 is located primarily in the nucleus and contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal polar/acidic region. Yeast proteins, NGR1 and NAM8, show high sequence similarity with SECp43. NGR1 is a putative glucose-repressible protein that binds both RNA and single-stranded DNA (ssDNA). It may function in regulating cell growth in early log phase, possibly through its participation in RNA metabolism. NGR1 contains three RRMs, two of which are followed by a glutamine-rich stretch that may be involved in transcriptional activity. In addition, NGR1 has an asparagine-rich region near the C-terminus which also harbors a methionine-rich region. NAM8 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. NAM8 also contains three RRMs.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 28380262  99 EFSVWVGDLSSDVDDYQLYKVFSSKFTSIKTAKVILDSL-GFSKGYGFVRFGIEDEQKSALYDMNGYiGLGTKPIKICNA 177
Cdd:cd12345   1 EHSLFVGDLAPDVTDYQLYETFSARYPSVRGAKVVMDPVtGRSKGYGFVRFGDESEQDRALTEMQGV-YLGSRPIRVSPA 79

                .
gi 28380262 178 V 178
Cdd:cd12345  80 T 80

RNA recognition motif 2 (RRM2) found in tRNA selenocysteine-associated protein 1 (SECp43) and similar proteins; This subfamily corresponds to the RRM2 in tRNA selenocysteine-associated protein 1 (SECp43), yeast negative growth regulatory protein NGR1 (RBP1), yeast protein NAM8, and similar proteins. SECp43 is an RNA-binding protein associated specifically with eukaryotic selenocysteine tRNA [tRNA(Sec)]. It may play an adaptor role in the mechanism of selenocysteine insertion. SECp43 is located primarily in the nucleus and contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal polar/acidic region. Yeast proteins, NGR1 and NAM8, show high sequence similarity with SECp43. NGR1 is a putative glucose-repressible protein that binds both RNA and single-stranded DNA (ssDNA). It may function in regulating cell growth in early log phase, possibly through its participation in RNA metabolism. NGR1 contains three RRMs, two of which are followed by a glutamine-rich stretch that may be involved in transcriptional activity. In addition, NGR1 has an asparagine-rich region near the C-terminus which also harbors a methionine-rich region. NAM8 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. NAM8 also contains three RRMs.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 28380262  99 EFSVWVGDLSSDVDDYQLYKVFSSKFTSIKTAKVILDSL-GFSKGYGFVRFGIEDEQKSALYDMNGYiGLGTKPIKICNA 177
Cdd:cd12345   1 EHSLFVGDLAPDVTDYQLYETFSARYPSVRGAKVVMDPVtGRSKGYGFVRFGDESEQDRALTEMQGV-YLGSRPIRVSPA 79

                .
gi 28380262 178 V 178
Cdd:cd12345  80 T 80

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 28380262   102 VWVGDLSSDVDDYQLYKVFSsKFTSIKTAKVILDSLGFSKGYGFVRFGIEDEQKSALYDMNGYIgLGTKPIK 173
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFS-KFGPIKSIRLVRDETGRSKGFAFVEFEDEEDAEKAIEALNGKE-LGGRELK 70

RNA recognition motif;

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 28380262      8 LWMGSLESYMTENFIIAAFRKMGEdPTTVRLMRNKYTGEPAGYCFVNFISDDHALDAMHKLNGKPIPG 75
Cdd:smart00360   2 LFVGNLPPDTTEEELRELFSKFGK-VESVRLVRDKETGKSKGFAFVEFESEEDAEKALEALNGKELDG 68

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

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 28380262 104 VGDLSSDVDDYQLYKVFSsKFTSIKTAKVILDSL-GFSKGYGFVRFGIEDEQKSALYDMNGYIgLGTKPIKICNAVPKPK 182
Cdd:COG0724   6 VGNLPYSVTEEDLRELFS-EYGEVTSVKLITDREtGRSRGFGFVEMPDDEEAQAAIEALNGAE-LMGRTLKVNEARPREE 83

                .
gi 28380262 183 S 183
Cdd:COG0724  84 R 84

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 28380262     8 LWMGSLESYMTENFIIAAFRKMGeDPTTVRLMRnKYTGEPAGYCFVNFISDDHALDAMHKLNGKPIPGT 76
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFG-PIKSIRLVR-DETGRSKGFAFVEFEDEEDAEKAIEALNGKELGGR 67

RNA recognition motif 2 (RRM2) found in tRNA selenocysteine-associated protein 1 (SECp43) and similar proteins; This subfamily corresponds to the RRM2 in tRNA selenocysteine-associated protein 1 (SECp43), yeast negative growth regulatory protein NGR1 (RBP1), yeast protein NAM8, and similar proteins. SECp43 is an RNA-binding protein associated specifically with eukaryotic selenocysteine tRNA [tRNA(Sec)]. It may play an adaptor role in the mechanism of selenocysteine insertion. SECp43 is located primarily in the nucleus and contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal polar/acidic region. Yeast proteins, NGR1 and NAM8, show high sequence similarity with SECp43. NGR1 is a putative glucose-repressible protein that binds both RNA and single-stranded DNA (ssDNA). It may function in regulating cell growth in early log phase, possibly through its participation in RNA metabolism. NGR1 contains three RRMs, two of which are followed by a glutamine-rich stretch that may be involved in transcriptional activity. In addition, NGR1 has an asparagine-rich region near the C-terminus which also harbors a methionine-rich region. NAM8 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. NAM8 also contains three RRMs.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 28380262  99 EFSVWVGDLSSDVDDYQLYKVFSSKFTSIKTAKVILDSL-GFSKGYGFVRFGIEDEQKSALYDMNGYiGLGTKPIKICNA 177
Cdd:cd12345   1 EHSLFVGDLAPDVTDYQLYETFSARYPSVRGAKVVMDPVtGRSKGYGFVRFGDESEQDRALTEMQGV-YLGSRPIRVSPA 79

                .
gi 28380262 178 V 178
Cdd:cd12345  80 T 80

RNA recognition motif 1 (RRM1) found in tRNA selenocysteine-associated protein 1 (SECp43) and similar proteins; This subfamily corresponds to the RRM1 in tRNA selenocysteine-associated protein 1 (SECp43), yeast negative growth regulatory protein NGR1 (RBP1), yeast protein NAM8, and similar proteins. SECp43 is an RNA-binding protein associated specifically with eukaryotic selenocysteine tRNA [tRNA(Sec)]. It may play an adaptor role in the mechanism of selenocysteine insertion. SECp43 is located primarily in the nucleus and contains two N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a C-terminal polar/acidic region. Yeast proteins, NGR1 and NAM8, show high sequence similarity with SECp43. NGR1 is a putative glucose-repressible protein that binds both RNA and single-stranded DNA (ssDNA). It may function in regulating cell growth in early log phase, possibly through its participation in RNA metabolism. NGR1 contains three RRMs, two of which are followed by a glutamine-rich stretch that may be involved in transcriptional activity. In addition, NGR1 has an asparagine-rich region near the C-terminus which also harbors a methionine-rich region. NAM8 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. NAM8 also contains three RRMs.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 28380262   8 LWMGSLESYMTENFIIAAFRKMGEDPTTVRLMRNKYTGEPAGYCFVNFISDDHALDAMHKLNGKPIPGTNpiVRFRLNSA 87
Cdd:cd12344   2 LWMGDLEPWMDEAYISSCFAKTGEEVVSVKIIRNKQTGKSAGYCFVEFATQEAAEQALEHLNGKPIPNTQ--QRFRLNWA 79

                ...
gi 28380262  88 SNS 90
Cdd:cd12344  80 SFS 82

RNA recognition motif 1 (RRM1) found in yeast negative growth regulatory protein NGR1, yeast protein NAM8 and similar proteins; This subgroup corresponds to the RRM1 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), two of which are 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 subgroup also includes NAM8, 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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 28380262   7 QLWMGSLESYMTENFIIAAFRKMGEDPTTVRLMRNKYTG--EPAGYCFVNFISDDHALDAMHKlNGKPIPGTNPiVRFRL 84
Cdd:cd12611   1 TLWMGDLEPWMDENFIKQIWASLGLKPVNVKVIRSKSGGlnGNAGYCFVEFPSPHAAQNALSL-NGTPIPGSES-RTFKL 78

                ....*.
gi 28380262  85 NSASNS 90
Cdd:cd12611  79 NWASGG 84

ELAV/HuD family splicing factor; This model describes the ELAV/HuD subfamily of splicing factors found in metazoa. HuD stands for the human paraneoplastic encephalomyelitis antigen D of which there are 4 variants in human. ELAV stnds for the Drosophila Embryonic lethal abnormal visual protein. ELAV-like splicing factors are also known in human as HuB (ELAV-like protein 2), HuC (ELAV-like protein 3, Paraneoplastic cerebellar degeneration-associated antigen) and HuR (ELAV-like protein 1). These genes are most closely related to the sex-lethal subfamily of splicing factors found in Dipteran insects (TIGR01659). These proteins contain 3 RNA-recognition motifs (rrm: pfam00076).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 28380262    17 MTENFIIAAFRKMGEdPTTVRLMRNKYTGEPAGYCFVNFISDDHALDAMHKLNGkpipgtnpiVRFRLNSASNSYKLPGN 96
Cdd:TIGR01661  15 MTQEEIRSLFTSIGE-IESCKLVRDKVTGQSLGYGFVNYVRPEDAEKAVNSLNG---------LRLQNKTIKVSYARPSS 84

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 28380262    97 E--REFSVWVGDLSSDVDDYQLYKVFsSKFTSIKTAKVILDSL-GFSKGYGFVRFGIEDEQKSALYDMNGYIGLG-TKPI 172
Cdd:TIGR01661  85 DsiKGANLYVSGLPKTMTQHELESIF-SPFGQIITSRILSDNVtGLSKGVGFIRFDKRDEADRAIKTLNGTTPSGcTEPI 163

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 28380262   173 --KICN--AVPKPK---SELGGAVGEGNTNYGYGSGMTAAGGTdysqyydPTSTYWQGYQAWQGYYEQAGASITDAAAYY 245
Cdd:TIGR01661 164 tvKFANnpSSSNSKgllSQLEAVQNPQTTRVPLSTILTAAGIG-------PMHHAAARFRPSAGDFTAVLAHQQQQHAVA 236

                         250       260
                  ....*....|....*....|....
gi 28380262   246 QQAMSQSHSNP------QTLAQHA 263
Cdd:TIGR01661 237 QQHAAQRASPPatdgqtAGLAAGA 260

sex-lethal family splicing factor; This model describes the sex-lethal family of splicing factors found in Dipteran insects. The sex-lethal phenotype, however, may be limited to the Melanogasters and closely related species. In Drosophila the protein acts as an inhibitor of splicing. This subfamily is most closely related to the ELAV/HUD subfamily of splicing factors (TIGR01661).

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 28380262    17 MTENFIIAAFRKMGedP-TTVRLMRNKYTGEPAGYCFVNFISDDHALDAMHKLNGkpipgtnpiVRFRLNSASNSYKLPG 95
Cdd:TIGR01659 119 MTDRELYALFRTIG--PiNTCRIMRDYKTGYSFGYAFVDFGSEADSQRAIKNLNG---------ITVRNKRLKVSYARPG 187

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 28380262    96 NE--REFSVWVGDLSSDVDDYQLYKVFsSKFTSIKTAKVILDSL-GFSKGYGFVRFGIEDEQKSALYDMNGYIGLG-TKP 171
Cdd:TIGR01659 188 GEsiKDTNLYVTNLPRTITDDQLDTIF-GKYGQIVQKNILRDKLtGTPRGVAFVRFNKREEAQEAISALNNVIPEGgSQP 266

                         170       180       190
                  ....*....|....*....|....*....|....*....
gi 28380262   172 IKICNAVPKPKSELG---GAVGEGNTNYGYGSGMTAAGG 207
Cdd:TIGR01659 267 LTVRLAEEHGKAKAHhymSQMGHGNMGNMGHGNMGMAGG 305

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 28380262 102 VWVGDLSSDVDDYQLYKVFSsKFTSIKTAKVILDSLGFSKGYGFVRFGIEDEQKSALYDMNGYIgLGTKPIKI 174
Cdd:cd00590   1 LFVGNLPPDTTEEDLRELFS-KFGEVVSVRIVRDRDGKSKGFAFVEFESPEDAEKALEALNGTE-LGGRPLKV 71

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 28380262 103 WVGDLSSDVDDYQLYKVFSsKFTSIKTAKVILDSLGFSKGYGFVRFGIEDEQKSALYDMNGYIgLGTKPI 172
Cdd:cd12381   5 YVKNLDDTIDDEKLREEFS-PFGTITSAKVMTDEGGRSKGFGFVCFSSPEEATKAVTEMNGRI-IGGKPL 72

RNA recognition motif;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 28380262    101 SVWVGDLSSDVDDYQLYKVFSsKFTSIKTAKVILDSL-GFSKGYGFVRFGIEDEQKSALYDMNGYIgLGTKPIKI 174
Cdd:smart00360   1 TLFVGNLPPDTTEEELRELFS-KFGKVESVRLVRDKEtGKSKGFAFVEFESEEDAEKALEALNGKE-LDGRPLKV 73

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 28380262    44 TGEPAGYCFVNFISDDHALDAMHKLNGKPIPGTNPIV-RFRlnsaSNSYKLPGNEREFS-VWVGDLSSDVDDYQLYKVFS 121
Cdd:TIGR01628 125 NGKSRGYGFVHFEKEESAKAAIQKVNGMLLNDKEVYVgRFI----KKHEREAAPLKKFTnLYVKNLDPSVNEDKLRELFA 200

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 28380262   122 sKFTSIKTAKVILDSLGFSKGYGFVRFGIEDEQKSALYDMNGY-IGLGTKPIKICNAVPKPKSE 184
Cdd:TIGR01628 201 -KFGEITSAAVMKDGSGRSRGFAFVNFEKHEDAAKAVEEMNGKkIGLAKEGKKLYVGRAQKRAE 263

RNA recognition motif 1 (RRM1) 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 first RRM motif.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 28380262 101 SVWVGDLSSDVDDYQLYKVFsSKFTSIKTAKVILDSL-GFSKGYGFVRFGIEDEQKSALYDMNgYIGLGTKPIKI 174
Cdd:cd21601   2 ALFIGDLDKDVTEEMLRDIF-SKYKSLVSVKICLDSEtKKSLGYGYLNFSDKEDAEKAIEEFN-YTPIFGKEVRI 74

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 28380262   8 LWMGSLESYMTENFIIAAFRKMGEdPTTVRLMRNKyTGEPAGYCFVNFISDDHALDAMHKLNGKPIPG 75
Cdd:cd00590   1 LFVGNLPPDTTEEDLRELFSKFGE-VVSVRIVRDR-DGKSKGFAFVEFESPEDAEKALEALNGTELGG 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 28380262 102 VWVGDLSSDVDDYQLYKVFSsKFTSIKTAKVILDSLGFSKGYGFVRFGIEDEQKSALYDMNG 163
Cdd:cd12380   4 VYVKNFGEDVDDDELKELFE-KYGKITSAKVMKDDSGKSKGFGFVNFENHEAAQKAVEELNG 64

RNA recognition motif 2 (RRM2) found found in type I polyadenylate-binding proteins; This subfamily corresponds to the RRM2 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 a 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. 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 28380262 102 VWVGDLSSDVDDYQLYKVFSsKFTSIKTAKVILDSLGFSKGYGFVRFGIEDEQKSALYDMNG 163
Cdd:cd12379   5 IFIKNLDKSIDNKALYDTFS-AFGNILSCKVATDENGGSKGYGFVHFETEEAAERAIEKVNG 65

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 28380262 102 VWVGDLSSDVDDYQLYKVFSsKFTSIKTAKVILDSLGFSKGYGFVRFGIEDE 153
Cdd:cd12412   5 IFVGGIDWDTTEEELREFFS-KFGKVKDVKIIKDRAGVSKGYGFVTFETQED 55

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 28380262 102 VWVGDLSSDVDDYQLYKVFSsKFTSIKTAKVILD-SLGFSKGYGFVRFGIEDEQKSALYDMNGY 164
Cdd:cd21608   2 LYVGNLSWDTTEDDLRDLFS-EFGEVESAKVITDrETGRSRGFGFVTFSTAEAAEAAIDALNGK 64

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

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 28380262   8 LWMGSLESYMTENFIIAAFRKMGEdPTTVRLMRNK---YTGEPAGYCFVNFISDDHALDAMHKLNGKPIPGTNPIVR 81
Cdd:cd12355   2 LWIGNLDPRLTEYHLLKLLSKYGK-IKKFDFLFHKtgpLKGQPRGYCFVTFETKEEAEKAIECLNGKLALGKKLVVR 77

RNA recognition motif 1 (RRM1) and 2 (RRM2) found in RNA-binding protein 5 (RBM5) and similar proteins; This subfamily includes the RRM1 and RRM2 of RNA-binding protein 5 (RBM5 or LUCA15 or H37) and RNA-binding protein 10 (RBM10 or S1-1), and the RRM2 of RNA-binding protein 6 (RBM6 or NY-LU-12 or g16 or DEF-3). These RBMs share high sequence homology and may play an important role in regulating apoptosis. RBM5 is a known modulator of apoptosis. It may also act as a tumor suppressor or an RNA splicing factor. RBM6 has been predicted to be a nuclear factor based on its nuclear localization signal. Both, RBM6 and RBM5, specifically bind poly(G) RNA. RBM10 is a paralog of RBM5. It may play an important role in mRNA generation, processing and degradation in several cell types. The rat homolog of human RBM10 is protein S1-1, a hypothetical RNA binding protein with poly(G) and poly(U) binding capabilities. All family members contain two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), two C2H2-type zinc fingers, and a G-patch/D111 domain.

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                ....*....|....*....|....*....|....*....|....*....|....*...
gi 28380262  18 TENFIIAAFRKMGEDPT-TVRLMRNKYTGEPAGYCFVNFISDDHALDAMHKLNGKPIP 74
Cdd:cd12313  15 TEEDILSALQAHADLPIkDVRLIRDKLTGTSRGFAFVEFSSLEDATQVMDALQNLLPP 72

RNA recognition motif 2 (RRM2) found in yeast nuclear polyadenylated RNA-binding protein 4 (Hrp1p or Nab4p) and similar proteins; This subfamily corresponds to the RRM1 of Hrp1p and similar proteins. Hrp1p or Nab4p, also termed cleavage factor IB (CFIB), is a sequence-specific trans-acting factor that is essential for mRNA 3'-end formation in yeast Saccharomyces cerevisiae. It can be UV cross-linked to RNA and specifically recognizes the (UA)6 RNA element required for both, the cleavage and poly(A) addition steps. Moreover, Hrp1p can shuttle between the nucleus and the cytoplasm, and play an additional role in the export of mRNAs to the cytoplasm. Hrp1p also interacts with Rna15p and Rna14p, two components of CF1A. In addition, Hrp1p functions as a factor directly involved in modulating the activity of the nonsense-mediated mRNA decay (NMD) pathway; it binds specifically to a downstream sequence element (DSE)-containing RNA and interacts with Upf1p, a component of the surveillance complex, further triggering the NMD pathway. Hrp1p contains two central RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and an arginine-glycine-rich region harboring repeats of the sequence RGGF/Y.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 28380262 102 VWVGDLSSDVDDYQLYKVFSsKFTSIKTAKVILD-SLGFSKGYGFVRFGIEDEQKSALYdmNGYIGLGTKPIKICNAVPK 180
Cdd:cd12330   2 IFVGGLAPDVTEEEFKEYFE-QFGTVVDAVVMLDhDTGRSRGFGFVTFDSESAVEKVLS--KGFHELGGKKVEVKRATPK 78

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 28380262   101 SVWVGDLSSDVDDYQLYKVFsSKFTSIKTAKVILDSL-GFSKGYGFVRFGIEDEQKSALYDMNgYIGLGTKPIKI 174
Cdd:TIGR01628   2 SLYVGDLDPDVTEAKLYDLF-KPFGPVLSVRVCRDSVtRRSLGYGYVNFQNPADAERALETMN-FKRLGGKPIRI 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.

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                ....*....|....*....|....*....|....*....|....*....|....
gi 28380262  17 MTENFIIAAFRKMGeDPTTVRLMRNKYTGEPAGYCFVNFISDDHALDAMHKLNG 70
Cdd:cd12375  11 MTQEELRSLFGAIG-PIESCKLVRDKITGQSLGYGFVNYRDPNDARKAINTLNG 63

RNA recognition motif 2 (RRM2) found in the Hu proteins family, Drosophila sex-lethal (SXL), and similar proteins; This subfamily corresponds to the RRM2 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 the ubiquitously expressed Hu family member. It has a variety of biological functions mostly related to the regulation of cellular response to DNA damage and other types of stress. Hu proteins perform their cytoplasmic and nuclear molecular functions by coordinately regulating functionally related mRNAs. In the cytoplasm, Hu proteins recognize and bind to AU-rich RNA elements (AREs) in the 3' untranslated regions (UTRs) of certain target mRNAs, such as GAP-43, vascular epithelial growth factor (VEGF), the glucose transporter GLUT1, eotaxin and c-fos, and stabilize those ARE-containing mRNAs. They also bind and regulate the translation of some target mRNAs, such as neurofilament M, GLUT1, and p27. In the nucleus, Hu proteins function as regulators of polyadenylation and alternative splicing. Each Hu protein contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). RRM1 and RRM2 may cooperate in binding to an ARE. RRM3 may help to maintain the stability of the RNA-protein complex, and might also bind to poly(A) tails or be involved in protein-protein interactions. Also included in this subfamily is 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 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 RRMs that show high preference to bind single-stranded, uridine-rich target RNA transcripts.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 28380262 101 SVWVGDLSSDVDDYQLYKVFSsKFTSIKTAKVILDSL-GFSKGYGFVRFGIEDEQKSALYDMNGYIGLG-TKPIKI 174
Cdd:cd12376   2 NLYVSGLPKTMTQKELEQLFS-QYGRIITSRILRDQLtGVSRGVGFIRFDKRIEAEEAIKGLNGQKPEGaSEPITV 76

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
                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 28380262   8 LWMGSLESYMTENFIIAAFRKMGEdPTTVRLMRNKYTGEPAGYCFVNFISDDHALDAMHKLNG 70
Cdd:cd12284   1 LYVGSLHFNITEDMLRGIFEPFGK-IEFVQLQKDPETGRSKGYGFIQFRDAEDAKKALEQLNG 62

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

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 28380262   7 QLWMGSLESYMTENFIIAAFRKMGEdPTTVRLMRNKYTGEPAGYCFVNFISDDHALDAMHKLNGKPIPG 75
Cdd:cd12449   2 KLFVGGLSFDTNEQSLEEVFSKYGQ-ISEVVVVKDRETQRSRGFGFVTFENPDDAKDAMMAMNGKSLDG 69