RNA recognition motif 3 (RRM3) found in Schizosaccharomyces pombe mRNA export factor Crp79, meiotically up-regulated gene 28 protein (Mug28) and similar proteins; Crp79, also called meiotic expression up-regulated protein 5 (Mug5), or polyadenylate-binding protein crp79, or PABP, or poly(A)-binding protein, is an auxiliary mRNA export factor that binds the poly(A) tail of mRNA and is involved in the export of mRNA from the nucleus to the cytoplasm. Mug28 is a meiosis-specific protein that regulates spore wall formation. Members in this family contain three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the three RRM motif.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 470318545 605 IDPKNLYIKNLDDDIISHPSDIETLFKPFGTIVSSHLAVVPGTGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRVFVS 684
Cdd:cd21622    1 IDPCNLFVKNLDDTVITNKEDLEQLFSPFGQIVSSYLATYPGTGISKGFGFVAFSKPEDAAKAKETLNGVMVGRKRIFVS 80

                         90
                 ....*....|..
gi 470318545 685 WAERRADREKRL 696
Cdd:cd21622   81 YAERKEDREKRL 92

RNA recognition motif 2 (RRM2) found in Schizosaccharomyces pombe mRNA export factor Crp79, meiotically up-regulated gene 28 protein (Mug28) and similar proteins; Crp79, also called meiotic expression up-regulated protein 5 (Mug5), or polyadenylate-binding protein crp79, or PABP, or poly(A)-binding protein, is an auxiliary mRNA export factor that binds the poly(A) tail of mRNA and is involved in the export of mRNA from the nucleus to the cytoplasm. Mug28 is a meiosis-specific protein that regulates spore wall formation. Members in this family contain three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the second RRM motif.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 470318545 196 LSVFNLPYEMTPKDLFCLFSELGRVEGAFIYNVVDSRGRRVGEVAMGSFYHAKKALESLNNTTLNGYILELAFK 269
Cdd:cd21621    1 LTVLNLPTDMTPKDLYNLFSEHGKVEGTAINQVPDNRGRRYGEVAMNSYEDCQKALEYFNGYVYKGYILEVFYK 74

RNA recognition motif 3 (RRM3) found in Schizosaccharomyces pombe mRNA export factor Crp79, meiotically up-regulated gene 28 protein (Mug28) and similar proteins; Crp79, also called meiotic expression up-regulated protein 5 (Mug5), or polyadenylate-binding protein crp79, or PABP, or poly(A)-binding protein, is an auxiliary mRNA export factor that binds the poly(A) tail of mRNA and is involved in the export of mRNA from the nucleus to the cytoplasm. Mug28 is a meiosis-specific protein that regulates spore wall formation. Members in this family contain three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the three RRM motif.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 470318545 605 IDPKNLYIKNLDDDIISHPSDIETLFKPFGTIVSSHLAVVPGTGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRVFVS 684
Cdd:cd21622    1 IDPCNLFVKNLDDTVITNKEDLEQLFSPFGQIVSSYLATYPGTGISKGFGFVAFSKPEDAAKAKETLNGVMVGRKRIFVS 80

                         90
                 ....*....|..
gi 470318545 685 WAERRADREKRL 696
Cdd:cd21622   81 YAERKEDREKRL 92

RNA recognition motif 2 (RRM2) found in Schizosaccharomyces pombe mRNA export factor Crp79, meiotically up-regulated gene 28 protein (Mug28) and similar proteins; Crp79, also called meiotic expression up-regulated protein 5 (Mug5), or polyadenylate-binding protein crp79, or PABP, or poly(A)-binding protein, is an auxiliary mRNA export factor that binds the poly(A) tail of mRNA and is involved in the export of mRNA from the nucleus to the cytoplasm. Mug28 is a meiosis-specific protein that regulates spore wall formation. Members in this family contain three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the second RRM motif.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 470318545 196 LSVFNLPYEMTPKDLFCLFSELGRVEGAFIYNVVDSRGRRVGEVAMGSFYHAKKALESLNNTTLNGYILELAFK 269
Cdd:cd21621    1 LTVLNLPTDMTPKDLYNLFSEHGKVEGTAINQVPDNRGRRYGEVAMNSYEDCQKALEYFNGYVYKGYILEVFYK 74

RNA recognition motif;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 470318545   609 NLYIKNLDDDIisHPSDIETLFKPFGTIVSSHLAVVPGTGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRVFV 683
Cdd:smart00360   1 TLFVGNLPPDT--TEEELRELFSKFGKVESVRLVRDKETGKSKGFAFVEFESEEDAEKALEALNGKELDGRPLKV 73

RNA recognition motif;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 470318545    68 IYVGNLEMTINNDALMKIFGRFGTIESVYrppIHTDKA-DRTTHFAFIKYTDAESAQRAMQQADNILLGRRRLVV 141
Cdd:smart00360   2 LFVGNLPPDTTEEELRELFSKFGKVESVR---LVRDKEtGKSKGFAFVEFESEEDAEKALEALNGKELDGRPLKV 73

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 470318545   68 IYVGNLEMTINNDALMKIFGRFGTIESVYrppIHTDKADRTTHFAFIKYTDAESAQRAMQQADNILLGRRRL 139
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGPIKSIR---LVRDETGRSKGFAFVEFEDEEDAEKAIEALNGKELGGREL 69

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 470318545  196 LSVFNLPYEMTPKDLFCLFSELGRVEGAFIYNVVDSRGRRVGEVAMGSFYHAKKALESLNNTTLNGYILE 265
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGPIKSIRLVRDETGRSKGFAFVEFEDEEDAEKAIEALNGKELGGRELK 70

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

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 470318545 193 SKILSVFNLPYEMTPKDLFCLFSELGRVEGAFIynVVD---SRGRRVGEVAMGSFYHAKKALESLNNTTLNG 261
Cdd:COG0724    1 SMKIYVGNLPYSVTEEDLRELFSEYGEVTSVKL--ITDretGRSRGFGFVEMPDDEEAQAAIEALNGAELMG 70

Family of unknown function (DUF5585); This is a family of unknown function found in chordata.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 470318545  412 TVTAYQPVSSGLKKTEAT--TKLTTPVTPVAPTVSMVSAAPVSVTSSASTVSAP-----TVSVVSGTSSASTVSA--PTV 482
Cdd:pfam17823 155 SAAPRAAIAAASAPHAASpaPRTAASSTTAASSTTAASSAPTTAASSAPATLTPargisTAATATGHPAAGTALAavGNS 234

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 470318545  483 SVVSGTSSASTVSVPTASVVSGTSAVSTVTEASATSSASTAFSASPVPSTSVASAAFSTSIASVA---STASVVSVNTSQ 559
Cdd:pfam17823 235 SPAAGTVTAAVGTVTPAALATLAAAAGTVASAAGTINMGDPHARRLSPAKHMPSDTMARNPAAPMgaqAQGPIIQVSTDQ 314

                  ....*....
gi 470318545  560 ---NTKTEP 565
Cdd:pfam17823 315 pvhNTAGEP 323

RNA recognition motif 3 (RRM3) found in Schizosaccharomyces pombe mRNA export factor Crp79, meiotically up-regulated gene 28 protein (Mug28) and similar proteins; Crp79, also called meiotic expression up-regulated protein 5 (Mug5), or polyadenylate-binding protein crp79, or PABP, or poly(A)-binding protein, is an auxiliary mRNA export factor that binds the poly(A) tail of mRNA and is involved in the export of mRNA from the nucleus to the cytoplasm. Mug28 is a meiosis-specific protein that regulates spore wall formation. Members in this family contain three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the three RRM motif.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 470318545 605 IDPKNLYIKNLDDDIISHPSDIETLFKPFGTIVSSHLAVVPGTGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRVFVS 684
Cdd:cd21622    1 IDPCNLFVKNLDDTVITNKEDLEQLFSPFGQIVSSYLATYPGTGISKGFGFVAFSKPEDAAKAKETLNGVMVGRKRIFVS 80

                         90
                 ....*....|..
gi 470318545 685 WAERRADREKRL 696
Cdd:cd21622   81 YAERKEDREKRL 92

RNA recognition motif 2 (RRM2) found in Schizosaccharomyces pombe mRNA export factor Crp79, meiotically up-regulated gene 28 protein (Mug28) and similar proteins; Crp79, also called meiotic expression up-regulated protein 5 (Mug5), or polyadenylate-binding protein crp79, or PABP, or poly(A)-binding protein, is an auxiliary mRNA export factor that binds the poly(A) tail of mRNA and is involved in the export of mRNA from the nucleus to the cytoplasm. Mug28 is a meiosis-specific protein that regulates spore wall formation. Members in this family contain three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the second RRM motif.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 470318545 196 LSVFNLPYEMTPKDLFCLFSELGRVEGAFIYNVVDSRGRRVGEVAMGSFYHAKKALESLNNTTLNGYILELAFK 269
Cdd:cd21621    1 LTVLNLPTDMTPKDLYNLFSEHGKVEGTAINQVPDNRGRRYGEVAMNSYEDCQKALEYFNGYVYKGYILEVFYK 74

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        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 470318545 609 NLYIKNLDDDIishpsDIETL---FKPFGTIVSSHLAVVPGtGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRVFVSW 685
Cdd:cd12381    3 NLYVKNLDDTI-----DDEKLreeFSPFGTITSAKVMTDEG-GRSKGFGFVCFSSPEEATKAVTEMNGRIIGGKPLYVAL 76

                 ...
gi 470318545 686 AER 688
Cdd:cd12381   77 AQR 79

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

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 470318545  68 IYVGNLEMTINNDALMKIFGRFGTIESVYrppIHTDKADRTTHFAFIKYTDAESAQRAMQQADNILLGRRRLVVR 142
Cdd:cd00590    1 LFVGNLPPDTTEEDLRELFSKFGEVVSVR---IVRDRDGKSKGFAFVEFESPEDAEKALEALNGTELGGRPLKVS 72

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

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 470318545 624 SDIETLFKPFGTIVSSHLAVVPGTGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRVFVS 684
Cdd:cd12362   13 QDLYQLFAPFGNVVSAKVFVDKNTGRSKGFGFVSYDNPLSAQAAIKAMNGFQVGGKRLKVQ 73

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.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 470318545 609 NLYIKNLDDDIIShpSDIETLFKPFGTIVSSHLAVvPGTGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRVFV 683
Cdd:cd12379    4 NIFIKNLDKSIDN--KALYDTFSAFGNILSCKVAT-DENGGSKGYGFVHFETEEAAERAIEKVNGMLLNGKKVFV 75

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 470318545  610 LYIKNLDDDIisHPSDIETLFKPFGTIVSSHLaVVPGTGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRV 681
Cdd:pfam00076   1 LFVGNLPPDT--TEEDLKDLFSKFGPIKSIRL-VRDETGRSKGFAFVEFEDEEDAEKAIEALNGKELGGREL 69

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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 470318545 609 NLYIKNLDDDIisHPSDIETLFKPFGTIVSshlAVV--PGTGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRVFVSWA 686
Cdd:cd12380    3 NVYVKNFGEDV--DDDELKELFEKYGKITS---AKVmkDDSGKSKGFGFVNFENHEAAQKAVEELNGKELNGKKLYVGRA 77

                 ...
gi 470318545 687 ERR 689
Cdd:cd12380   78 QKK 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 470318545   68 IYVGNLEMTINNDALMKIFGRFGTIESVYrppIHTDKADRTTHFAFIKYTDAESAQRAMQQADNILLGRRRL 139
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGPIKSIR---LVRDETGRSKGFAFVEFEDEEDAEKAIEALNGKELGGREL 69

RNA recognition motif 3 (RRM3) found in RNA-binding protein 19 (RBM19) and RNA recognition motif 2 found in multiple RNA-binding domain-containing protein 1 (MRD1); This subfamily corresponds to the RRM3 of RBM19 and RRM2 of MRD1. RBM19, also termed RNA-binding domain-1 (RBD-1), is a nucleolar protein conserved in eukaryotes involved in ribosome biogenesis by processing rRNA and is essential for preimplantation development. It has a unique domain organization containing 6 conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). MRD1 is encoded by a novel yeast gene MRD1 (multiple RNA-binding domain). It is well conserved in yeast and its homologs exist in all eukaryotes. MRD1 is present in the nucleolus and the nucleoplasm. It interacts with the 35 S precursor rRNA (pre-rRNA) and U3 small nucleolar RNAs (snoRNAs). It is essential for the initial processing at the A0-A2 cleavage sites in the 35 S pre-rRNA. MRD1 contains 5 conserved RRMs, which may play an important structural role in organizing specific rRNA processing events.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 470318545 610 LYIKNLDddIISHPSDIETLFKPFGTIVSSHLAVVPGTGISKGYGFVAFSKAEEAIKAKKSLDGSMV-GR 678
Cdd:cd12316    2 LFVRNLP--FTATEDELRELFEAFGKISEVHIPLDKQTKRSKGFAFVLFVIPEDAVKAYQELDGSIFqGR 69

RNA recognition motif 3 in fungal pre-messenger RNA splicing protein 24 (Prp24) and similar proteins; This subfamily corresponds to the RRM3 of Prp24, also termed U4/U6 snRNA-associated-splicing factor PRP24 (U4/U6 snRNP), an RNA-binding protein with four well conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). It facilitates U6 RNA base-pairing with U4 RNA during spliceosome assembly. Prp24 specifically binds free U6 RNA primarily with RRMs 1 and 2 and facilitates pairing of U6 RNA bases with U4 RNA bases. Additionally, it may also be involved in dissociation of the U4/U6 complex during spliceosome activation.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 470318545  68 IYVGNLEMTINNDALMKIFGRFGTIESVYRPPIHTDKADRTTH-FAFIKYTDAESAQRAMqQADNILLGRRRLVV 141
Cdd:cd12298    3 IRVRNLDFELDEEALRGIFEKFGEIESINIPKKQKNRKGRHNNgFAFVTFEDADSAESAL-QLNGTLLDNRKISV 76

RNA recognition motif 2 (RRM2) found in the Hu proteins family; This subfamily corresponds to the RRM2 of 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. Moreover, 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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 470318545 609 NLYIKNLDDDIISHpsDIETLFKPFGTIVSSHLAVVPGTGISKGYGFVAFSKAEEAIKAKKSLDGS 674
Cdd:cd12652    2 NLYVSGLPKTMTQK--ELEQLFSQFGRIITSRILCDNVTGLSRGVGFIRFDKRVEAERAIKALNGT 65

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 470318545  600 PESQPIDPKNLYIKNLDDDIISHpsDIETLFKPFGTIVSSHLAVVPGTGISKGYGFVAFSKAEEAIKAKKSLDGS 674
Cdd:TIGR01661  82 PSSDSIKGANLYVSGLPKTMTQH--ELESIFSPFGQIITSRILSDNVTGLSKGVGFIRFDKRDEADRAIKTLNGT 154

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 470318545   62 EDFSNaIYVGNLEMTINNDALMKIFGRFGTIESVyrpPIHTDKADRTTHFAFIKYTDAESAQRAMQQADNILLGrrrlVV 141
Cdd:TIGR01628 176 KKFTN-LYVKNLDPSVNEDKLRELFAKFGEITSA---AVMKDGSGRSRGFAFVNFEKHEDAAKAVEEMNGKKIG----LA 247

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 470318545  142 RPRIRSYVSRSINRV--PSLSPQKSNQYpplsysymppqyylpyntHVNQNFMSKI--LSVFNLPYEMTPKDLFCLFSEL 217
Cdd:TIGR01628 248 KEGKKLYVGRAQKRAerEAELRRKFEEL------------------QQERKMKAQGvnLYVKNLDDTVTDEKLRELFSEC 309

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 470318545  218 GRVEGAFIynVVDSRG--RRVGEVAMGSFYHAKKALESLNNTTLNG---YI------------LELAF--------KPPT 272
Cdd:TIGR01628 310 GEITSAKV--MLDEKGvsRGFGFVCFSNPEEANRAVTEMHGRMLGGkplYValaqrkeqrrahLQDQFmqlqprmrQLPM 387

                         250       260       270       280       290
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 470318545  273 LS----TQFIPPVNSGHSMMYVPPN------------SVYPSWQYSPSLYPVPNQVPMP 315
Cdd:TIGR01628 388 GSpmggAMGQPPYYGQGPQQQFNGQplgwprmsmmptPMGPGGPLRPNGLAPMNAVRAP 446

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 470318545 196 LSVFNLPYEMTPKDLFCLFSELGRVEGAFIYNVVDSRGRRVGEVAMGSFYHAKKALESLNNTTLNGYILEL 266
Cdd:cd00590    1 LFVGNLPPDTTEEDLRELFSKFGEVVSVRIVRDRDGKSKGFAFVEFESPEDAEKALEALNGTELGGRPLKV 71

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

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 470318545  68 IYVGNLEMTINNDALMKIFGRFGTIESVYrppIHTD-KADRTTHFAFIKYTDAESAQRAMQQADNILLGRRRLVV 141
Cdd:cd12284    1 LYVGSLHFNITEDMLRGIFEPFGKIEFVQ---LQKDpETGRSKGYGFIQFRDAEDAKKALEQLNGFELAGRPMKV 72

RNA recognition motif (RRM) found in RNA-binding protein with serine-rich domain 1 (RNPS1) and similar proteins; This subfamily corresponds to the RRM of RNPS1 and its eukaryotic homologs. RNPS1, also termed RNA-binding protein prevalent during the S phase, or SR-related protein LDC2, was originally characterized as a general pre-mRNA splicing activator, which activates both constitutive and alternative splicing of pre-mRNA in vitro.It has been identified as a protein component of the splicing-dependent mRNP complex, or exon-exon junction complex (EJC), and is directly involved in mRNA surveillance. Furthermore, RNPS1 is a splicing regulator whose activator function is controlled in part by CK2 (casein kinase II) protein kinase phosphorylation. It can also function as a squamous-cell carcinoma antigen recognized by T cells-3 (SART3)-binding protein, and is involved in the regulation of mRNA splicing. RNPS1 contains an N-terminal serine-rich (S) domain, a central RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNP (ribonucleoprotein domain), and the C-terminal arginine/serine/proline-rich (RS/P) domain.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 470318545  68 IYVGNLEMTINNDALMKIFGRFGTIESVYRPPihtdkaDRTTH----FAFIKYTDAESAQRAMQQADN 131
Cdd:cd12365    1 LHVGKLTRNVTKDHLKEIFSVYGTVKNVDLPI------DREPNlprgYAYVEFESPEDAEKAIKHMDG 62

RNA recognition motif 1 (RRM1) found in yeast nucleolar protein 4 (Nop4p) and similar proteins; This subgroup corresponds to the RRM1 of Nop4p (also known as Nop77p), encoded by YPL043W from Saccharomyces cerevisiae. It is an essential nucleolar protein involved in processing and maturation of 27S pre-rRNA and biogenesis of 60S ribosomal subunits. Nop4p has four RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 470318545 608 KNLYIKNLDDDIIShpSDIETLFKPFGTIvsSHLAVV--PGTGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRVFVSW 685
Cdd:cd12674    1 TTLFVRNLPFDVTL--ESLTDFFSDIGPV--KHAVVVtdPETKKSRGYGFVSFSTHDDAEEALAKLKNRKLSGHILKLDF 76

                 ....
gi 470318545 686 AERR 689
Cdd:cd12674   77 AKPR 80

RNA recognition motif 2 (RRM2) found found in vertebrate ribonucleoprotein PTB-binding 1 (raver-1); This subgroup corresponds to the RRM2 of raver-1, a ubiquitously expressed heterogeneous nuclear ribonucleoprotein (hnRNP) that serves as a co-repressor of the nucleoplasmic splicing repressor polypyrimidine tract-binding protein (PTB)-directed splicing of select mRNAs. It shuttles between the cytoplasm and the nucleus and can accumulate in the perinucleolar compartment, a dynamic nuclear substructure that harbors PTB. Raver-1 also modulates focal adhesion assembly by binding to the cytoskeletal proteins, including alpha-actinin, vinculin, and metavinculin (an alternatively spliced isoform of vinculin) at adhesion complexes, particularly in differentiated muscle tissue. Raver-1 contains three N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), two putative nuclear localization signals (NLS) at the N- and C-termini, a central leucine-rich region, and a C-terminal region harboring two PTB-binding [SG][IL]LGxxP motifs. Raver1 binds to PTB through the PTB-binding motifs at its C-terminal half, and binds to other partners, such as RNA having the sequence UCAUGCAGUCUG, through its N-terminal RRMs. Interestingly, the 12-nucleotide RNA having the sequence UCAUGCAGUCUG with micromolar affinity is found in vinculin mRNA. Additional research indicates that the RRM1 of raver-1 directs its interaction with the tail domain of activated vinculin. Then the raver1/vinculin tail (Vt) complex binds to vinculin mRNA, which is permissive for vinculin binding to F-actin.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 470318545 627 ETLFKPFGTIVSSHLAVVPGTGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRVFVSWAE 687
Cdd:cd12665   17 EELVRPFGNLERCFLVYSETTGHSKGYGFVEYMKKDSAARAKSDLLGKQLGTRTLYVHWTD 77

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

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 470318545  66 NAIYVGNLEMTINNDALMKIFGRFGTIESVYRPPIHTDKAdrttHFAFIKYTDAESAQRAMQQADNILLGRRRLVV 141
Cdd:cd21603    1 NAIFVKNLPLDTNNDEILDFFSKVGPIKSVFTSPKYKYNS----LWAFVTYKKGSDTEKAIKLLNGTLFKGRTIEV 72

RNA recognition motif 3 (RRM3) found in the Hu proteins family; This subfamily corresponds to the RRM3 of the Hu proteins family which represent 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.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 470318545 609 NLYIKNLDDDiiSHPSDIETLFKPFGTIVSSHLAVVPGTGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRVFVS 684
Cdd:cd12377    1 CIFVYNLAPD--ADESLLWQLFGPFGAVQNVKIIRDFTTNKCKGYGFVTMTNYDEAAVAIASLNGYRLGGRVLQVS 74

RNA recognition motif 2 (RRM2) found in granule-associated RNA binding proteins p40-TIA-1 and TIAR; This subfamily corresponds to the RRM2 of nucleolysin TIA-1 isoform p40 (p40-TIA-1 or TIA-1) and nucleolysin TIA-1-related protein (TIAR), both of which are granule-associated RNA binding proteins involved in inducing apoptosis in cytotoxic lymphocyte (CTL) target cells. TIA-1 and TIAR share high sequence similarity. They are expressed in a wide variety of cell types. TIA-1 can be phosphorylated by a serine/threonine kinase that is activated during Fas-mediated apoptosis. TIAR is mainly localized in the nucleus of hematopoietic and nonhematopoietic cells. It is translocated from the nucleus to the cytoplasm in response to exogenous triggers of apoptosis. Both, TIA-1 and TIAR, bind specifically to poly(A) but not to poly(C) homopolymers. They are composed of three N-terminal highly homologous RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and a glutamine-rich C-terminal auxiliary domain containing a lysosome-targeting motif. TIA-1 and TIAR interact with RNAs containing short stretches of uridylates and their RRM2 can mediate the specific binding to uridylate-rich RNAs. The C-terminal auxiliary domain may be responsible for interacting with other proteins. In addition, TIA-1 and TIAR share a potential serine protease-cleavage site (Phe-Val-Arg) localized at the junction between their RNA binding domains and their C-terminal auxiliary domains.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 470318545 624 SDIETL-----FKPFGTIVSSHLAVVPGTGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRVFVSW 685
Cdd:cd12353    9 PEIETEdlkeaFAPFGEISDARVVKDTQTGKSKGYGFVSFVKKEDAENAIQGMNGQWLGGRNIRTNW 75

RNA recognition motif 2 (RRM2) found in splicing factor 3B subunit 4 (SF3B4) and similar proteins; This subfamily corresponds to the RRM2 of SF3B4, also termed pre-mRNA-splicing factor SF3b 49 kDa (SF3b50), or spliceosome-associated protein 49 (SAP 49). SF3B4 is a component of the multiprotein complex splicing factor 3b (SF3B), an integral part of the U2 small nuclear ribonucleoprotein (snRNP) and the U11/U12 di-snRNP. SF3B is essential for the accurate excision of introns from pre-messenger RNA, and is involved in the recognition of the pre-mRNA's branch site within the major and minor spliceosomes. SF3B4 functions to tether U2 snRNP with pre-mRNA at the branch site during spliceosome assembly. It is an evolutionarily highly conserved protein with orthologs across diverse species. SF3B4 contains two closely adjacent N-terminal RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). It binds directly to pre-mRNA and also interacts directly and highly specifically with another SF3B subunit called SAP 145.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 470318545 609 NLYIKNLDDDIishpsDIETL---FKPFGTIVSS-HLAVVPGTGISKGYGFVAFSKAEEAIKAKKSLDGSMVGRKRVFVS 684
Cdd:cd12335    3 NLFIGNLDPEV-----DEKLLydtFSAFGVILQTpKIMRDPDTGNSKGFGFVSFDSFEASDAAIEAMNGQYLCNRPITVS 77

                 ....*
gi 470318545 685 WAERR 689
Cdd:cd12335   78 YAFKK 82

RNA recognition motif 1 (RRM1) found in chloroplastic plastid-specific 30S ribosomal protein 2 (PSRP-2) and similar proteins; PSRP-2, also called chloroplastic 30S ribosomal protein 2, or chloroplastic small ribosomal subunit protein cS22, is a component of the chloroplast ribosome (chloro-ribosome), a dedicated translation machinery responsible for the synthesis of chloroplast genome-encoded proteins, including proteins of the transcription and translation machinery and components of the photosynthetic apparatus. It binds single strand DNA (ssDNA) and RNA in vitro. It exhibits RNA chaperone activity and regulates negatively resistance responses to abiotic stresses during seed germination (e.g. salt, dehydration, and low temperature) and seedling growth (e.g. salt). The family also includes Nicotiana sylvestris chloroplastic 33 kDa ribonucleoprotein (NsCP33) and Arabidopsis thaliana chloroplastic 31 kDa ribonucleoprotein (AtCP31A). NsCP33 may be involved in splicing and/or processing of chloroplast RNA's. AtCP31A, also called RNA-binding protein 1/2/3 (AtRBP33), or RNA-binding protein CP31A, or RNA-binding protein RNP-T, or RNA-binding protein cp31, is required for specific RNA editing events in chloroplasts and stabilizes specific chloroplast mRNAs, as well as for normal chloroplast development under cold stress conditions by stabilizing transcripts of numerous mRNAs under these conditions. CP31A may modulate telomere replication through RNA binding domains. Members in this family contain two RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the first RRM motif.

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gi 470318545  68 IYVGNLEMTINNDALMKIFGRFGTIESVyrpPIHTDK-ADRTTHFAFIKYTDAESAQRAMQQADNILLGRRRLVVR 142
Cdd:cd21609    2 LYVGNIPRNVTSEELAKIFEEAGTVEIA---EVMYDRyTGRSRGFGFVTMGSVEDAKAAIEKLNGTEVGGREIKVN 74