Selenocysteine tRNA 1 associated proteins; This entry represents the C-terminal region of Selenocysteine tRNA 1 associated proteins (Trnau1ap also known as Secp43). Family members found in Eukaryotes have been shown to serve an essential role in the synthesis of selenoproteins, which have critical functions in numerous biological processes. Selenium deficiency results in a variety of diseases, including cardiac disease. Trnau1ap proteins harbor RNA recognition motifs (RRM) pfam00076 and Tyr-rich region found in the C-terminal. The Tyr-rich region (amino acids 185-225) is conserved among several mammals, including human, chimp, dog, cattle, mouse and rat. Furthermore, constitutive deletion of exons corresponding to the Tyr-rich region in mouse resulted in embryonic lethality.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2293430394 166 QWGYDQNTGSYSYSYPQYGYTQS-TMQTYEEVGDDALEDPAPQLDVTEANKEFMEQSEELYDALMDCHWQPLDTVSSEIP 244
Cdd:pfam17654  22 QWGYDQYNGYYSYSYPQYGYTPApTTQEAEQQDEDPLEDPNLELDVEELNKEFMERSEELYDALMNCHWQPLDSVTSEIP 101

Selenocysteine tRNA 1 associated proteins; This entry represents the C-terminal region of Selenocysteine tRNA 1 associated proteins (Trnau1ap also known as Secp43). Family members found in Eukaryotes have been shown to serve an essential role in the synthesis of selenoproteins, which have critical functions in numerous biological processes. Selenium deficiency results in a variety of diseases, including cardiac disease. Trnau1ap proteins harbor RNA recognition motifs (RRM) pfam00076 and Tyr-rich region found in the C-terminal. The Tyr-rich region (amino acids 185-225) is conserved among several mammals, including human, chimp, dog, cattle, mouse and rat. Furthermore, constitutive deletion of exons corresponding to the Tyr-rich region in mouse resulted in embryonic lethality.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2293430394 166 QWGYDQNTGSYSYSYPQYGYTQS-TMQTYEEVGDDALEDPAPQLDVTEANKEFMEQSEELYDALMDCHWQPLDTVSSEIP 244
Cdd:pfam17654  22 QWGYDQYNGYYSYSYPQYGYTPApTTQEAEQQDEDPLEDPNLELDVEELNKEFMERSEELYDALMNCHWQPLDSVTSEIP 101

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 2293430394   3 ASLWMGDLEPYMDENFISRAFATMGeTVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLpGATPAKRFKln 82
Cdd:TIGR01628   1 ASLYVGDLDPDVTEAKLYDLFKPFG-PVLSVRVCRDSVTRRSLGYGYVNFQNPADAERALETMNFKRL-GGKPIRIMW-- 76

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2293430394  83 yatygKQPDNSPEYS----LFVGDLTPDVDDGMLYEFFVKV--YPSCrggKVVLDQTGVSKS 138
Cdd:TIGR01628  77 -----SQRDPSLRRSgvgnIFVKNLDKSVDNKALFDTFSKFgnILSC---KVATDENGKSRG 130

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 2293430394   5 LWMGDLEPYMDENFISRAFATMGEtVMSVKIIRnRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPG 72
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGP-IKSIRLVR-DETGRSKGFAFVEFEDEEDAEKAIEALNGKELGG 66

glycine-rich RNA-binding protein 4; Provisional

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2293430394   1 MAASLWMGDLEPYMDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPGatpaKRFK 80
Cdd:PLN03134   33 MSTKLFIGGLSWGTDDASLRDAFAHFGD-VVDAKVIVDRETGRSRGFGFVNFNDEGAATAAISEMDGKELNG----RHIR 107

                  ....*
gi 2293430394  81 LNYAT 85
Cdd:PLN03134  108 VNPAN 112

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 2293430394   4 SLWMGDLEPYMDENFISRAFATMGETVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPGAtpAKRFKLNY 83
Cdd:cd12344     1 TLWMGDLEPWMDEAYISSCFAKTGEEVVSVKIIRNKQTGKSAGYCFVEFATQEAAEQALEHLNGKPIPNT--QQRFRLNW 78

                  ....
gi 2293430394  84 ATYG 87
Cdd:cd12344    79 ASFS 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 2293430394   5 LWMGDLEPYMDENFISRAFATMGETVMSVKIIRNRLTGI--PAGYCFVEFADLATAEKCLHKiNGKPLPGaTPAKRFKLN 82
Cdd:cd12611     2 LWMGDLEPWMDENFIKQIWASLGLKPVNVKVIRSKSGGLngNAGYCFVEFPSPHAAQNALSL-NGTPIPG-SESRTFKLN 79

                  ....*
gi 2293430394  83 YATYG 87
Cdd:cd12611    80 WASGG 84

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
                  ....*....|....*....|....*....|....*....|....
gi 2293430394  95 EYSLFVGDLTPDVDDGMLYEFFVKVYPSCRGGKVVLDQ-TGVSK 137
Cdd:cd12345     1 EHSLFVGDLAPDVTDYQLYETFSARYPSVRGAKVVMDPvTGRSK 44

RNA recognition motif;

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2293430394    4 SLWMGDLEPYMDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPG 72
Cdd:smart00360   1 TLFVGNLPPDTTEEELRELFSKFGK-VESVRLVRDKETGKSKGFAFVEFESEEDAEKALEALNGKELDG 68

RNA recognition motif 2 (RRM2) found in yeast negative growth regulatory protein NGR1, yeast protein NAM8 and similar proteins; This subgroup corresponds to the RRM2 of NGR1 and NAM8. NGR1, also termed RNA-binding protein RBP1, is a putative glucose-repressible protein that binds both, RNA and single-stranded DNA (ssDNA), in yeast. It may function in regulating cell growth in early log phase, possibly through its participation in RNA metabolism. NGR1 contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a glutamine-rich stretch that may be involved in transcriptional activity. In addition, NGR1 has an asparagine-rich region near the carboxyl terminus which also harbors a methionine-rich region. The family also includes protein NAM8, which is a putative RNA-binding protein that acts as a suppressor of mitochondrial splicing deficiencies when overexpressed in yeast. It may be a non-essential component of the mitochondrial splicing machinery. Like NGR1, NAM8 contains two RRMs.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....
gi 2293430394  95 EYSLFVGDLTPDVDDGMLYEFFVKVYPSCRGGKVVLD-QTGVSK 137
Cdd:cd12613     1 EYSIFVGDLSPTTNESDLVSLFQSRFPSCKSAKIMTDpVTGVSR 44

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 2293430394   4 SLWMGDLEPYMDENFISRAFATMGETVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPGatpaKRFKLNY 83
Cdd:cd12345     3 SLFVGDLAPDVTDYQLYETFSARYPSVRGAKVVMDPVTGRSKGYGFVRFGDESEQDRALTEMQGVYLGS----RPIRVSP 78

                  ..
gi 2293430394  84 AT 85
Cdd:cd12345    79 AT 80

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        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2293430394   5 LWMGDLEPYMDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPGatpaKRFKLNYA 84
Cdd:cd21608     2 LYVGNLSWDTTEDDLRDLFSEFGE-VESAKVITDRETGRSRGFGFVTFSTAEAAEAAIDALNGKELDG----RSIVVNEA 76

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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2293430394  10 LEPYMDENFISRAF-ATMGETVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPGATPAKRFKLNYA 84
Cdd:cd12313    10 LDVLTTEEDILSALqAHADLPIKDVRLIRDKLTGTSRGFAFVEFSSLEDATQVMDALQNLLPPFKIDGRVVSVSYA 85

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 2293430394  14 MDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGkplpGATPAKRFKLNYA 84
Cdd:cd12375    11 MTQEELRSLFGAIGP-IESCKLVRDKITGQSLGYGFVNYRDPNDARKAINTLNG----LDLENKRLKVSYA 76

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.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 2293430394   5 LWMGDLEPYMDENFISRAFATMGeTVMSVKIIRNR---LTGIPAGYCFVEFADLATAEKCLHKINGK 68
Cdd:cd12355     2 LWIGNLDPRLTEYHLLKLLSKYG-KIKKFDFLFHKtgpLKGQPRGYCFVTFETKEEAEKAIECLNGK 67

RNA recognition motif 1 (RRM1) found in the Hu proteins family; This subfamily corresponds to the RRM1 of the Hu proteins family which 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. HuR has an anti-apoptotic function during early cell stress response. It binds to mRNAs and enhances the expression of several anti-apoptotic proteins, such as p21waf1, p53, and prothymosin alpha. HuR also has pro-apoptotic function by promoting apoptosis when cell death is unavoidable. Furthermore, HuR may be important in muscle differentiation, adipogenesis, suppression of inflammatory response and modulation of gene expression in response to chronic ethanol exposure and amino acid starvation. 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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2293430394  10 LEPYMDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLpgatPAKRFKLNYA 84
Cdd:cd12650     8 LPQNMTQDEIRSLFSSIGE-IESCKLIRDKVTGQSLGYGFVNYVDPSDAEKAINTLNGLRL----QNKTIKVSYA 77

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2293430394  12 PY-MDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPG 72
Cdd:COG0724    10 PYsVTEEDLRELFSEYGE-VTSVKLITDRETGRSRGFGFVEMPDDEEAQAAIEALNGAELMG 70

RNA recognition motif (RRM) found in cleavage stimulation factor subunit 2 (CSTF2), yeast ortholog mRNA 3'-end-processing protein RNA15 and similar proteins; This subfamily corresponds to the RRM domain of CSTF2, its tau variant and eukaryotic homologs. CSTF2, also termed cleavage stimulation factor 64 kDa subunit (CstF64), is the vertebrate conterpart of yeast mRNA 3'-end-processing protein RNA15. It is expressed in all somatic tissues and is one of three cleavage stimulatory factor (CstF) subunits required for polyadenylation. CstF64 contains an N-terminal RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain), a CstF77-binding domain, a repeated MEARA helical region and a conserved C-terminal domain reported to bind the transcription factor PC-4. During polyadenylation, CstF interacts with the pre-mRNA through the RRM of CstF64 at U- or GU-rich sequences within 10 to 30 nucleotides downstream of the cleavage site. CSTF2T, also termed tauCstF64, is a paralog of the X-linked cleavage stimulation factor CstF64 protein that supports polyadenylation in most somatic cells. It is expressed during meiosis and subsequent haploid differentiation in a more limited set of tissues and cell types, largely in meiotic and postmeiotic male germ cells, and to a lesser extent in brain. The loss of CSTF2T will cause male infertility, as it is necessary for spermatogenesis and fertilization. Moreover, CSTF2T is required for expression of genes involved in morphological differentiation of spermatids, as well as for genes having products that function during interaction of motile spermatozoa with eggs. It promotes germ cell-specific patterns of polyadenylation by using its RRM to bind to different sequence elements downstream of polyadenylation sites than does CstF64. The family also includes yeast ortholog mRNA 3'-end-processing protein RNA15 and similar proteins. RNA15 is a core subunit of cleavage factor IA (CFIA), an essential transcriptional 3'-end processing factor from Saccharomyces cerevisiae. RNA recognition by CFIA is mediated by an N-terminal RRM, which is contained in the RNA15 subunit of the complex. The RRM of RNA15 has a strong preference for GU-rich RNAs, mediated by a binding pocket that is entirely conserved in both yeast and vertebrate RNA15 orthologs.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2293430394   4 SLWMGDLePY-MDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPG 72
Cdd:cd12398     2 SVFVGNI-PYdATEEQLKEIFSEVGP-VVSFRLVTDRETGKPKGYGFCEFRDAETALSAVRNLNGYELNG 69

RNA recognition motif (RRM) found in serine/arginine-rich splicing factor 3 (SRSF3) and similar proteins; This subfamily corresponds to the RRM of two serine/arginine (SR) proteins, serine/arginine-rich splicing factor 3 (SRSF3) and serine/arginine-rich splicing factor 7 (SRSF7). SRSF3, also termed pre-mRNA-splicing factor SRp20, modulates alternative splicing by interacting with RNA cis-elements in a concentration- and cell differentiation-dependent manner. It is also involved in termination of transcription, alternative RNA polyadenylation, RNA export, and protein translation. SRSF3 is critical for cell proliferation, and tumor induction and maintenance. It can shuttle between the nucleus and cytoplasm. SRSF7, also termed splicing factor 9G8, plays a crucial role in both constitutive splicing and alternative splicing of many pre-mRNAs. Its localization and functions are tightly regulated by phosphorylation. SRSF7 is predominantly present in the nuclear and can shuttle between nucleus and cytoplasm. It cooperates with the export protein, Tap/NXF1, helps mRNA export to the cytoplasm, and enhances the expression of unspliced mRNA. Moreover, SRSF7 inhibits tau E10 inclusion through directly interacting with the proximal downstream intron of E10, a clustering region for frontotemporal dementia with Parkinsonism (FTDP) mutations. Both SRSF3 and SRSF7 contain a single N-terminal RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and a C-terminal RS domain rich in serine-arginine dipeptides. The RRM domain is involved in RNA binding, and the RS domain has been implicated in protein shuttling and protein-protein interactions.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2293430394   5 LWMGDLEPYMDENFISRAFATMGeTVMSVKIIRNrltgiPAGYCFVEFADLATAEKCLHKINGKPLPGA 73
Cdd:cd12373     2 VYVGNLGPRVTKRELEDAFEKYG-PLRNVWVARN-----PPGFAFVEFEDPRDAEDAVRALDGRRICGS 64

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 2293430394   5 LWMGDLEPYMDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPG 72
Cdd:cd12284     1 LYVGSLHFNITEDMLRGIFEPFGK-IEFVQLQKDPETGRSKGYGFIQFRDAEDAKKALEQLNGFELAG 67

RNA recognition motif 2 (RRM2) found in yeast negative growth regulatory protein NGR1, yeast protein NAM8 and similar proteins; This subgroup corresponds to the RRM2 of NGR1 and NAM8. NGR1, also termed RNA-binding protein RBP1, is a putative glucose-repressible protein that binds both, RNA and single-stranded DNA (ssDNA), in yeast. It may function in regulating cell growth in early log phase, possibly through its participation in RNA metabolism. NGR1 contains two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a glutamine-rich stretch that may be involved in transcriptional activity. In addition, NGR1 has an asparagine-rich region near the carboxyl terminus which also harbors a methionine-rich region. The family also includes protein NAM8, which is a putative RNA-binding protein that acts as a suppressor of mitochondrial splicing deficiencies when overexpressed in yeast. It may be a non-essential component of the mitochondrial splicing machinery. Like NGR1, NAM8 contains two RRMs.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2293430394   4 SLWMGDLEPYMDENFISRAFATMGETVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGK 68
Cdd:cd12613     3 SIFVGDLSPTTNESDLVSLFQSRFPSCKSAKIMTDPVTGVSRGYGFVRFSDENDQQRALIEMQGK 67

RNA recognition motif 1 (RRM1) found in vertebrate Hu-antigen B (HuB); This subgroup corresponds to the RRM1 of HuB, also termed ELAV-like protein 2 (ELAV-2), or ELAV-like neuronal protein 1, or nervous system-specific RNA-binding protein Hel-N1 (Hel-N1), one of the neuronal members of the Hu family. The neuronal Hu proteins play important roles in neuronal differentiation, plasticity and memory. HuB is also expressed in gonads and is up-regulated during neuronal differentiation of embryonic carcinoma P19 cells. Like other Hu proteins, HuB 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 AU-rich RNA element (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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2293430394  14 MDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLpgatPAKRFKLNYA 84
Cdd:cd12771    16 MTQEELKSLFGSIGE-IESCKLVRDKITGQSLGYGFVNYIEPKDAEKAINTLNGLRL----QTKTIKVSYA 81

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        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2293430394   5 LWMGDLEPYMDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPGAT 74
Cdd:cd12449     3 LFVGGLSFDTNEQSLEEVFSKYGQ-ISEVVVVKDRETQRSRGFGFVTFENPDDAKDAMMAMNGKSLDGRQ 71

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2293430394  13 YMDENFISRAFATMGETVMSV---KIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPGatpaKRFKLNYA 84
Cdd:cd12649     7 YLPQDLTDREFRALFRAIGPVntcKIVRDKKTGYSYGFGFVDFTSEEDAQRAIKTLNGLQLQN----KRLKVAYA 77

RNA recognition motif 2 (RRM2) found in vertebrate Hu-antigen B (HuB); This subgroup corresponds to the RRM2 of HuB, also termed ELAV-like protein 2 (ELAV-2), or ELAV-like neuronal protein 1, or nervous system-specific RNA-binding protein Hel-N1 (Hel-N1), one of the neuronal members of the Hu family. The neuronal Hu proteins play important roles in neuronal differentiation, plasticity and memory. HuB is also expressed in gonads. It is up-regulated during neuronal differentiation of embryonic carcinoma P19 cells. Like other Hu proteins, HuB 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 AU-rich RNA element (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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2293430394   3 ASLWMGDLEPYMDENFISRAFATMGETVMSvKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPGAT 74
Cdd:cd12775     6 ANLYVSGLPKTMTQKELEQLFSQYGRIITS-RILVDQVTGVSRGVGFIRFDKRIEAEEAIKGLNGQKPPGAT 76

RNA recognition motif (RRM) found in nuclear cap-binding protein subunit 2 (CBP20) and similar proteins; This subfamily corresponds to the RRM of CBP20, also termed nuclear cap-binding protein subunit 2 (NCBP2), or cell proliferation-inducing gene 55 protein, or NCBP-interacting protein 1 (NIP1). CBP20 is the small subunit of the nuclear cap binding complex (CBC), which is a conserved eukaryotic heterodimeric protein complex binding to 5'-capped polymerase II transcripts and plays a central role in the maturation of pre-mRNA and uracil-rich small nuclear RNA (U snRNA). CBP20 is most likely responsible for the binding of capped RNA. It contains an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and interacts with the second and third domains of CBP80, the large subunit of CBC.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2293430394   5 LWMGDLEPYMDENFISRAFATMGEtvmsVK-IIR--NRLTGIPAGYCFVEFADLATAEKCLHKING 67
Cdd:cd12240     1 LYVGNLSFYTTEEQIYELFSKCGD----IKrIIMglDKFKKTPCGFCFVEYYSREDAENAVKYLNG 62

RNA recognition motif 1 (RRM1) found in vertebrate Hu-antigen R (HuR); This subgroup corresponds to the RRM1 of HuR, also termed ELAV-like protein 1 (ELAV-1), a 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. HuR has an anti-apoptotic function during early cell stress response; it binds to mRNAs and enhances the expression of several anti-apoptotic proteins, such as p21waf1, p53, and prothymosin alpha. Meanwhile, HuR also has pro-apoptotic function by promoting apoptosis when cell death is unavoidable. Furthermore, HuR may be important in muscle differentiation, adipogenesis, suppression of inflammatory response and modulation of gene expression in response to chronic ethanol exposure and amino acid starvation. Like other Hu proteins, HuR 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 AU-rich RNA element (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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2293430394  14 MDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLpgatPAKRFKLNYA 84
Cdd:cd12769    14 MTQDELRSLFSSIGE-VESAKLIRDKVAGHSLGYGFVNYVTAKDAERAINTLNGLRL----QSKTIKVSYA 79

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 2293430394   3 ASLWMGDLEPYMDENFISRAFATMGETVMSvKIIRNRLTGIPAGYCFVEFADLATAEKCLHKING-KPLPGATP 75
Cdd:cd12376     1 ANLYVSGLPKTMTQKELEQLFSQYGRIITS-RILRDQLTGVSRGVGFIRFDKRIEAEEAIKGLNGqKPEGASEP 73

RNA recognition motif 1 (RRM1) found in vertebrate Hu-antigen C (HuC); This subgroup corresponds to the RRM1 of HuC, also termed ELAV-like protein 3 (ELAV-3), or paraneoplastic cerebellar degeneration-associated antigen, or paraneoplastic limbic encephalitis antigen 21 (PLE21), one of the neuronal members of the Hu family. The neuronal Hu proteins play important roles in neuronal differentiation, plasticity and memory. Like other Hu proteins, HuC 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 AU-rich RNA element (ARE). The AU-rich element binding of HuC can be inhibited by flavonoids. 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.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2293430394  14 MDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLpgatPAKRFKLNYA 84
Cdd:cd12772    16 MTQEEFKSLFGSIGD-IESCKLVRDKITGQSLGYGFVNYVDPNDADKAINTLNGLKL----QTKTIKVSYA 81

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 2293430394  14 MDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPGATpakrFKLNYA 84
Cdd:TIGR01661  15 MTQEEIRSLFTSIGE-IESCKLVRDKVTGQSLGYGFVNYVRPEDAEKAVNSLNGLRLQNKT----IKVSYA 80

RNA recognition motif 2 (RRM2) found in yeast nuclear and cytoplasmic polyadenylated RNA-binding protein PUB1 and similar proteins; This subgroup corresponds to the RRM2 of yeast protein PUB1, also termed ARS consensus-binding protein ACBP-60, or poly uridylate-binding protein, or poly(U)-binding protein. PUB1 has been identified as both, a heterogeneous nuclear RNA-binding protein (hnRNP) and a cytoplasmic mRNA-binding protein (mRNP), which may be stably bound to a translationally inactive subpopulation of mRNAs within the cytoplasm. It is distributed in both, the nucleus and the cytoplasm, and binds to poly(A)+ RNA (mRNA or pre-mRNA). Although it is one of the major cellular proteins cross-linked by UV light to polyadenylated RNAs in vivo, PUB1 is nonessential for cell growth in yeast. PUB1 also binds to T-rich single stranded DNA (ssDNA). However, there is no strong evidence implicating PUB1 in the mechanism of DNA replication. PUB1 contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a GAR motif (glycine and arginine rich stretch) that is located between RRM2 and RRM3.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2293430394   4 SLWMGDLEPYMDENFISRAFATMGeTVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLpGATPakrFKLNY 83
Cdd:cd12619     3 NIFVGDLSPEVTDAALFNAFSDFP-SCSDARVMWDQKTGRSRGYGFVSFRSQQDAQNAINSMNGKWL-GSRP---IRCNW 77

                  ..
gi 2293430394  84 AT 85
Cdd:cd12619    78 AT 79

RNA recognition motif 1 (RRM1) found in nucleolin-like proteins mainly from plants; This subfamily corresponds to the RRM1 of a group of plant nucleolin-like proteins, including nucleolin 1 (also termed protein nucleolin like 1) and nucleolin 2 (also termed protein nucleolin like 2, or protein parallel like 1). They play roles in the regulation of ribosome synthesis and in the growth and development of plants. Like yeast nucleolin, nucleolin-like proteins possess two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 2293430394  16 ENFISRAfatmgETVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKiNGKPLPG 72
Cdd:cd12450    17 ENFFSDC-----GEVVDVRIAMDRDDGRSKGFGHVEFASAESAQKALEK-SGQDLGG 67

RNA recognition motif 1 (RRM1) found in heterogeneous nuclear ribonucleoprotein hnRNP A and hnRNP D subfamilies and similar proteins; This subfamily corresponds to the RRM1 in the hnRNP A subfamily which includes hnRNP A0, hnRNP A1, hnRNP A2/B1, hnRNP A3 and similar proteins. hnRNP A0 is a low abundance hnRNP protein that has been implicated in mRNA stability in mammalian cells. hnRNP A1 is an abundant eukaryotic nuclear RNA-binding protein that may modulate splice site selection in pre-mRNA splicing. hnRNP A2/B1 is an RNA trafficking response element-binding protein that interacts with the hnRNP A2 response element (A2RE). hnRNP A3 is also a RNA trafficking response element-binding protein that participates in the trafficking of A2RE-containing RNA. The hnRNP A subfamily is characterized by two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), followed by a long glycine-rich region at the C-terminus. The hnRNP D subfamily includes hnRNP D0, hnRNP A/B, hnRNP DL and similar proteins. hnRNP D0 is a UUAG-specific nuclear RNA binding protein that may be involved in pre-mRNA splicing and telomere elongation. hnRNP A/B is an RNA unwinding protein with a high affinity for G- followed by U-rich regions. hnRNP A/B has also been identified as an APOBEC1-binding protein that interacts with apolipoprotein B (apoB) mRNA transcripts around the editing site and thus, plays an important role in apoB mRNA editing. hnRNP DL (or hnRNP D-like) is a dual functional protein that possesses DNA- and RNA-binding properties. It has been implicated in mRNA biogenesis at the transcriptional and post-transcriptional levels. All members in this subfamily contain two putative RRMs and a glycine- and tyrosine-rich C-terminus. The family also contains DAZAP1 (Deleted in azoospermia-associated protein 1), RNA-binding protein Musashi homolog Musashi-1, Musashi-2 and similar proteins. They all harbor two RRMs.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 2293430394  23 FATMGETVMSVkIIRNRLTGIPAGYCFVEFADLATAEKCL----HKINGK 68
Cdd:cd12325    19 FSKYGEVVDCV-VMKDPATGRSRGFGFVTFKDPSSVDAVLaarpHTLDGR 67

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
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 2293430394   4 SLWMGDLEPYMDENFISRAFATMgETVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPLPG 72
Cdd:cd21601     2 ALFIGDLDKDVTEEMLRDIFSKY-KSLVSVKICLDSETKKSLGYGYLNFSDKEDAEKAIEEFNYTPIFG 69

RNA recognition motif in nucleolar protein interacting with the FHA domain of pKI-67 (NIFK) and similar proteins; This subgroup corresponds to the RRM of NIFK and Nop15p. NIFK, also termed MKI67 FHA domain-interacting nucleolar phosphoprotein, or nucleolar phosphoprotein Nopp34, is a putative RNA-binding protein interacting with the forkhead associated (FHA) domain of pKi-67 antigen in a mitosis-specific and phosphorylation-dependent manner. It is nucleolar in interphase but associates with condensed mitotic chromosomes. This family also includes Saccharomyces cerevisiae YNL110C gene encoding ribosome biogenesis protein 15 (Nop15p), also termed nucleolar protein 15. Both, NIFK and Nop15p, contain an RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain).

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 2293430394   5 LWMGDLEPYMDENFISRAFATMGeTVMSVKIIRNRLTGIPAGYCFVEFADLATAE 59
Cdd:cd12307     2 VYIGHLPHGFYEPELRKYFSQFG-TVTRLRLSRSKKTGKSKGYAFVEFEDPEVAK 55

RNA recognition motif 2 (RRM2) found in U2 large nuclear ribonucleoprotein auxiliary factor U2AF 65 kDa subunit (U2AF65) and similar proteins; This subfamily corresponds to the RRM2 of U2AF65 and dU2AF50. U2AF65, also termed U2AF2, is the large subunit of U2 small nuclear ribonucleoprotein (snRNP) auxiliary factor (U2AF), which has been implicated in the recruitment of U2 snRNP to pre-mRNAs and is a highly conserved heterodimer composed of large and small subunits. U2AF65 specifically recognizes the intron polypyrimidine tract upstream of the 3' splice site and promotes binding of U2 snRNP to the pre-mRNA branchpoint. U2AF65 also plays an important role in the nuclear export of mRNA. It facilitates the formation of a messenger ribonucleoprotein export complex, containing both the NXF1 receptor and the RNA substrate. Moreover, U2AF65 interacts directly and specifically with expanded CAG RNA, and serves as an adaptor to link expanded CAG RNA to NXF1 for RNA export. U2AF65 contains an N-terminal RS domain rich in arginine and serine, followed by a proline-rich segment and three C-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The N-terminal RS domain stabilizes the interaction of U2 snRNP with the branch point (BP) by contacting the branch region, and further promotes base pair interactions between U2 snRNA and the BP. The proline-rich segment mediates protein-protein interactions with the RRM domain of the small U2AF subunit (U2AF35 or U2AF1). The RRM1 and RRM2 are sufficient for specific RNA binding, while RRM3 is responsible for protein-protein interactions. The family also includes Splicing factor U2AF 50 kDa subunit (dU2AF50), the Drosophila ortholog of U2AF65. dU2AF50 functions as an essential pre-mRNA splicing factor in flies. It associates with intronless mRNAs and plays a significant and unexpected role in the nuclear export of a large number of intronless mRNAs.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 2293430394   5 LWMGDLEPYMDENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEFADLATAEKCLHKINGKPL 70
Cdd:cd12231     3 LFIGGLPNYLNEDQVKELLQSFGK-LKAFNLVKDSATGLSKGYAFCEYVDDNVTDQAIAGLNGMQL 67

RNA recognition motif (RRM) found in U1 small nuclear ribonucleoprotein 70 kDa (U1-70K) and similar proteins; This subfamily corresponds to the RRM of U1-70K, also termed snRNP70, a key component of the U1 snRNP complex, which is one of the key factors facilitating the splicing of pre-mRNA via interaction at the 5' splice site, and is involved in regulation of polyadenylation of some viral and cellular genes, enhancing or inhibiting efficient poly(A) site usage. U1-70K plays an essential role in targeting the U1 snRNP to the 5' splice site through protein-protein interactions with regulatory RNA-binding splicing factors, such as the RS protein ASF/SF2. Moreover, U1-70K protein can specifically bind to stem-loop I of the U1 small nuclear RNA (U1 snRNA) contained in the U1 snRNP complex. It also mediates the binding of U1C, another U1-specific protein, to the U1 snRNP complex. U1-70K contains a conserved RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), followed by an adjacent glycine-rich region at the N-terminal half, and two serine/arginine-rich (SR) domains at the C-terminal half. The RRM is responsible for the binding of stem-loop I of U1 snRNA molecule. Additionally, the most prominent immunodominant region that can be recognized by auto-antibodies from autoimmune patients may be located within the RRM. The SR domains are involved in protein-protein interaction with SR proteins that mediate 5' splice site recognition. For instance, the first SR domain is necessary and sufficient for ASF/SF2 Binding. The family also includes Drosophila U1-70K that is an essential splicing factor required for viability in flies, but its SR domain is dispensable. The yeast U1-70k doesn't contain easily recognizable SR domains and shows low sequence similarity in the RRM region with other U1-70k proteins and therefore not included in this family. The RRM domain is dispensable for yeast U1-70K function.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 2293430394  15 DENFISRAFATMGEtVMSVKIIRNRLTGIPAGYCFVEF---ADLATAEKCLH--KINGK 68
Cdd:cd12236    14 TESKLRREFEKYGP-IKRVRLVRDKKTGKSRGYAFIEFeheRDMKAAYKHADgkKIDGR 71