Tetratricopeptide (TPR) repeat [General function prediction only];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 239050155 304 IGNEYAGSGNMEMAVKYFTDAIKHNPKEYKLFGNRSYCYEKMLQYEKSLTDAEIALSMNPKWIKGLYRKGRALVGLKRYN 383
Cdd:COG0457   14 LGLAYRRLGRYEEAIEDYEKALELDPDDAEALYNLGLAYLRLGRYEEALADYEQALELDPDDAEALNNLGLALQALGRYE 93

                         90
                 ....*....|....*....
gi 239050155 384 EARLTFGEVLKLDSSCKDA 402
Cdd:COG0457   94 EALEDYDKALELDPDDAEA 112

Amelogenins, cell adhesion proteins, play a role in the biomineralisation of teeth; They seem to regulate formation of crystallites during the secretory stage of tooth enamel development and are thought to play a major role in the structural organisation and mineralisation of developing enamel. The extracellular matrix of the developing enamel comprises two major classes of protein: the hydrophobic amelogenins and the acidic enamelins. Circular dichroism studies of porcine amelogenin have shown that the protein consists of 3 discrete folding units: the N-terminal region appears to contain beta-strand structures, while the C-terminal region displays characteristics of a random coil conformation. Subsequent studies on the bovine protein have indicated the amelogenin structure to contain a repetitive beta-turn segment and a "beta-spiral" between Gln112 and Leu138, which sequester a (Pro, Leu, Gln) rich region. The beta-spiral offers a probable site for interactions with Ca2+ ions. Muatations in the human amelogenin gene (AMGX) cause X-linked hypoplastic amelogenesis imperfecta, a disease characterised by defective enamel. A 9bp deletion in exon 2 of AMGX results in the loss of codons for Ile5, Leu6, Phe7 and Ala8, and replacement by a new threonine codon, disrupting the 16-residue (Met1-Ala16) amelogenin signal peptide.

                           10        20        30
                   ....*....|....*....|....*....|....*...
gi 239050155   462 QYKHPQPPAKFPLMPLPQNQPRPSMPTAAPLPPHSPEL 499
Cdd:smart00818 111 QQPMQPQPPVHPIPPLPPQPPLPPMFPMQPLPPLLPDL 148

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 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDRY-----CAFVNYTSKDSCEKAIQMFNGHAIDGTTLVVR 568
Cdd:cd00590    1 LFVGNLPPDTTEEDLRELFSKFGEVVSVRIVRDRDgkskgFAFVEFESPEDAEKALEALNGTELGGRPLKVS 72

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 239050155  502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPD-----RYCAFVNYTSKDSCEKAIQMFNGHAIDGTTL 565
Cdd:pfam00076   1 LFVGNLPPDTTEEDLKDLFSKFGPIKSIRLVRDetgrsKGFAFVEFEDEEDAEKAIEALNGKELGGREL 69

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

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDRY------CAFVNYTSKDSCEKAIQMFNGHAIDGTTLVVR 568
Cdd:COG0724    4 IYVGNLPYSVTEEDLRELFSEYGEVTSVKLITDREtgrsrgFGFVEMPDDEEAQAAIEALNGAELMGRTLKVN 76

UBA domain found in proteins involved in ubiquitin-mediated proteolysis; The ubiquitin-associated (UBA) domains are commonly occurring sequence motifs found in proteins involved in ubiquitin-mediated proteolysis. They contribute to ubiquitin (Ub) binding or ubiquitin-like (UbL) domain binding. However, some kinds of UBA domains can only the bind UbL domain, but not the Ub domain. UBA domains are normally comprised of compact three-helix bundles which contain a conserved GF/Y-loop. They can bind polyubiquitin with high affinity. They also bind monoubiquitin and other proteins. Most UBA domain-containing proteins have one UBA domain, but some harbor two or three UBA domains.

                         10        20
                 ....*....|....*....|....*...
gi 239050155 413 QLMEMGFTKEQSSNALIIH-GTVERALE 439
Cdd:cd14270    3 QLVEMGFSREQARRALRATnGDVEAAVE 30

Amelogenins, cell adhesion proteins, play a role in the biomineralisation of teeth; They seem to regulate formation of crystallites during the secretory stage of tooth enamel development and are thought to play a major role in the structural organisation and mineralisation of developing enamel. The extracellular matrix of the developing enamel comprises two major classes of protein: the hydrophobic amelogenins and the acidic enamelins. Circular dichroism studies of porcine amelogenin have shown that the protein consists of 3 discrete folding units: the N-terminal region appears to contain beta-strand structures, while the C-terminal region displays characteristics of a random coil conformation. Subsequent studies on the bovine protein have indicated the amelogenin structure to contain a repetitive beta-turn segment and a "beta-spiral" between Gln112 and Leu138, which sequester a (Pro, Leu, Gln) rich region. The beta-spiral offers a probable site for interactions with Ca2+ ions. Muatations in the human amelogenin gene (AMGX) cause X-linked hypoplastic amelogenesis imperfecta, a disease characterised by defective enamel. A 9bp deletion in exon 2 of AMGX results in the loss of codons for Ile5, Leu6, Phe7 and Ala8, and replacement by a new threonine codon, disrupting the 16-residue (Met1-Ala16) amelogenin signal peptide.

                           10        20        30
                   ....*....|....*....|....*....|....*...
gi 239050155   462 QYKHPQPPAKFPLMPLPQNQPRPSMPTAAPLPPHSPEL 499
Cdd:smart00818 111 QQPMQPQPPVHPIPPLPPQPPLPPMFPMQPLPPLLPDL 148

Ubiquitin associated domain; Present in Rad23, SNF1-like kinases. The newly-found UBA in p62 is known to bind ubiquitin.

                           10        20        30
                   ....*....|....*....|....*....|...
gi 239050155   410 QLMQLMEMGFTKEQSSNALII-HGTVERALESL 441
Cdd:smart00165   4 KIDQLLEMGFSREEALKALRAaNGNVERAAEYL 36

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 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDRY-----CAFVNYTSKDSCEKAIQMFNGHAIDGTTLVVR 568
Cdd:cd00590    1 LFVGNLPPDTTEEDLRELFSKFGEVVSVRIVRDRDgkskgFAFVEFESPEDAEKALEALNGTELGGRPLKVS 72

Tetratricopeptide (TPR) repeat [General function prediction only];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 239050155 304 IGNEYAGSGNMEMAVKYFTDAIKHNPKEYKLFGNRSYCYEKMLQYEKSLTDAEIALSMNPKWIKGLYRKGRALVGLKRYN 383
Cdd:COG0457   48 LGLAYLRLGRYEEALADYEQALELDPDDAEALNNLGLALQALGRYEEALEDYDKALELDPDDAEALYNLGLALLELGRYD 127

                         90
                 ....*....|....*....
gi 239050155 384 EARLTFGEVLKLDSSCKDA 402
Cdd:COG0457  128 EAIEAYERALELDPDDADA 146

Flp pilus assembly protein TadD, contains TPR repeats [Intracellular trafficking, secretion, and vesicular transport, Extracellular structures];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 239050155 308 YAGSGNMEMAVKYFTDAIKHNPKEYKLFGNRSYCYEKMLQYEKSLTDAEIALSMNPKWIKGLYRKGRALVGLKRYNEARL 387
Cdd:COG5010   64 YNKLGDFEESLALLEQALQLDPNNPELYYNLALLYSRSGDKDEAKEYYEKALALSPDNPNAYSNLAALLLSLGQDDEAKA 143

                 ....*....
gi 239050155 388 TFGEVLKLD 396
Cdd:COG5010  144 ALQRALGTS 152

Type IV pilus assembly protein PilF/PilW [Cell motility, Extracellular structures];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 239050155 308 YAGSGNMEMAVKYFTDAIKHNPKEYKLFGNRSYCYEKMLQYEKSLtDAEIALSMNPKWIKGLYRKGRALVGLKRYNEARL 387
Cdd:COG3063    2 YLKLGDLEEAEEYYEKALELDPDNADALNNLGLLLLEQGRYDEAI-ALEKALKLDPNNAEALLNLAELLLELGDYDEALA 80

                         90
                 ....*....|.
gi 239050155 388 TFGEVLKLDSS 398
Cdd:COG3063   81 YLERALELDPS 91

Lipoprotein NlpI, contains TPR repeats [Cell wall/membrane/envelope biogenesis];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 239050155 235 SNAAAIAKRKLEQKPKPDKKPAQANPKKQHESQQKATVMPQKQVAKEEVNGEESVNANDfiTRSVELAVIGNEYAGSGNM 314
Cdd:COG4785   12 LALAAAAASKAAILLAALLFAAVLALAIALADLALALAAAALAAAALAAERIDRALALP--DLAQLYYERGVAYDSLGDY 89

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 239050155 315 EMAVKYFTDAIKHNPKEYKLFGNRSYCYEKMLQYEKSLTDAEIALSMNPKWIKGLYRKGRALVGLKRYNEARLTFGEVLK 394
Cdd:COG4785   90 DLAIADFDQALELDPDLAEAYNNRGLAYLLLGDYDAALEDFDRALELDPDYAYAYLNRGIALYYLGRYELAIADLEKALE 169

                 ....
gi 239050155 395 LDSS 398
Cdd:COG4785  170 LDPN 173

RNA recognition motif 3 (RRM3) found in yeast nuclear and cytoplasmic polyadenylated RNA-binding protein PUB1 and similar proteins; This subfamily corresponds to the RRM3 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. PUB1 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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDRYCAFVNYTSKDSCEKAIQMFNGHAIDGTTL 565
Cdd:cd12622    3 VYVGNLPPEVTQADLIPLFQNFGVIEEVRVQRDKGFGFVKYDTHEEAALAIQQLNGQPFLGRPI 66

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

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDRYCAFVNYTSKDSCEKAIQMFNGHAIDGTTL 565
Cdd:cd12346    4 VFVGGLDPNVTEEDLRVLFGPFGEIVYVKIPPGKGCGFVQFVNRASAEAAIQKLQGTPIGGSRI 67

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 239050155  502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDR-------YcAFVNYTSKDSCEKAIQMFNGHAIDGTtlvvrypdriH 574
Cdd:TIGR01628   3 LYVGDLDPDVTEAKLYDLFKPFGPVLSVRVCRDSvtrrslgY-GYVNFQNPADAERALETMNFKRLGGK----------P 71

                          90
                  ....*....|....*..
gi 239050155  575 TRLGMS-RDASTESSGK 590
Cdd:TIGR01628  72 IRIMWSqRDPSLRRSGV 88

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

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDRYC------AFVNYTSKDSCEKAIQMFNGHAIDGTTLVVRY 569
Cdd:cd21608    2 LYVGNLSWDTTEDDLRDLFSEFGEVESAKVITDRETgrsrgfGFVTFSTAEAAEAAIDALNGKELDGRSIVVNE 75

Lipopolysaccharide biosynthesis regulator YciM/LapB, contains six TPR domains and a C-terminal metal-binding domain [Cell wall/membrane/envelope biogenesis];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 239050155 304 IGNEYAGSGNMEMAVKYFTDAIKHNPKEYKLFGNRSYCYEKMLQYEKSLTDAEIALSMNPKWIKGLYRKGRALVGLKRYN 383
Cdd:COG2956   82 LAQDYLKAGLLDRAEELLEKLLELDPDDAEALRLLAEIYEQEGDWEKAIEVLERLLKLGPENAHAYCELAELYLEQGDYD 161

                         90       100       110
                 ....*....|....*....|....*....|
gi 239050155 384 EARLTFGEVLKLDSSCKDAAEEIMRVQLMQ 413
Cdd:COG2956  162 EAIEALEKALKLDPDCARALLLLAELYLEQ 191

RNA recognition motif 2 in fungal pre-messenger RNA splicing protein 24 (Prp24) and similar proteins; This subfamily corresponds to the RRM2 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 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRvLPD-------RYCaFVNYTSKDSCEKAIQMFNGHAIDGTTLVVRYPD 571
Cdd:cd12297    3 LWVTNFPPSYDERSIRDLFGDYGVILSVR-LPSlryntsrRFC-YIDFTSPESARAAVELLNGLLEEGYTLVVKISD 77

Cytochrome c-type biogenesis protein CcmH/NrfG [Energy production and conversion, Posttranslational modification, protein turnover, chaperones];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 239050155 301 LAVIGNEYAGSGNMEMAVKYFTDAIKHNPKEYKLFGNRSYCYEKMLQYEKSLTDAEIALSMNPKWIKGLYRKGRALVGLK 380
Cdd:COG4235   20 WLLLGRAYLRLGRYDEALAAYEKALRLDPDNADALLDLAEALLAAGDTEEAEELLERALALDPDNPEALYLLGLAAFQQG 99

                         90       100       110
                 ....*....|....*....|....*....|....
gi 239050155 381 RYNEARLTFGEVLKLDSscKDAAEEIMRVQLMQL 414
Cdd:COG4235  100 DYAEAIAAWQKLLALLP--ADAPARLLEASIAEA 131

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        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDRY-----C-AFVNYTSKDSCEKAIQMFNGHAIDGTTLVV 567
Cdd:cd12362    1 LFVYHLPNEFTDQDLYQLFAPFGNVVSAKVFVDKNtgrskGfGFVSYDNPLSAQAAIKAMNGFQVGGKRLKV 72

Outer membrane protein chaperone/metalloprotease BepA/YfgC, contains M48 and TPR domains [Cell wall/membrane/envelope biogenesis, Posttranslational modification, protein turnover, chaperones];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 239050155 300 ELAVIGNEYAGSGNMEMAVKYFTDAIKHNPKEYKLFGNRSYCYEKMLQYEKSLTDAEIALSMNPKWIKGLYRKGRALVGL 379
Cdd:COG4783    6 ALYALAQALLLAGDYDEAEALLEKALELDPDNPEAFALLGEILLQLGDLDEAIVLLHEALELDPDEPEARLNLGLALLKA 85

                         90       100       110
                 ....*....|....*....|....*....|....
gi 239050155 380 KRYNEARLTFGEVLKLDSSCKDAAEEIMRVQLMQ 413
Cdd:COG4783   86 GDYDEALALLEKALKLDPEHPEAYLRLARAYRAL 119

RNA recognition motif (RRM) found in SR-related and CTD-associated factor 4 (SCAF4), SR-related and CTD-associated factor 8 (SCAF8) and similar proteins; This subfamily corresponds to the RRM in a new class of SCAFs (SR-like CTD-associated factors), including SCAF4, SCAF8 and similar proteins. The biological role of SCAF4 remains unclear, but it shows high sequence similarity to SCAF8 (also termed CDC5L complex-associated protein 7, or RNA-binding motif protein 16, or CTD-binding SR-like protein RA8). SCAF8 is a nuclear matrix protein that interacts specifically with a highly serine-phosphorylated form of the carboxy-terminal domain (CTD) of the largest subunit of RNA polymerase II (pol II). The pol II CTD plays a role in coupling transcription and pre-mRNA processing. In addition, SCAF8 co-localizes primarily with transcription sites that are enriched in nuclear matrix fraction, which is known to contain proteins involved in pre-mRNA processing. Thus, SCAF8 may play a direct role in coupling with both, transcription and pre-mRNA processing, processes. SCAF8 and SCAF4 both contain a conserved N-terminal CTD-interacting domain (CID), an atypical RNA recognition motif (RRM), also termed RBD (RNA binding domain) or RNPs (ribonucleoprotein domain), and serine/arginine-rich motifs.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDRYCAFVNYTSKDSCEKAIQMFNGHAIDGTTL 565
Cdd:cd12227    5 LWVGHLSKKVTQEELKNLFEEYGEIQSIDMIPPRGCAYVCMKTRQDAHRALQKLKNHKLRGKSI 68

RNA recognition motif 1 (RRM1) found in type I polyadenylate-binding proteins; This subfamily corresponds to the RRM1 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 mammals, 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 yeast PABP, a conserved poly(A) binding protein containing poly(A) tails that can be attached to the 3'-ends of mRNAs. The yeast PABP and its homologs may play important roles in the initiation of translation and in mRNA decay. Like vertebrate PABP-1, the yeast PABP contains four RRMs, a linker region, and a proline-rich CTD as well. The first two RRMs are mainly responsible for specific binding to poly(A). The proline-rich region may be involved in protein-protein interactions.

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gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDR-------YcAFVNYTSKDSCEKAIQMFNGHAIDG 562
Cdd:cd12378    2 LYVGDLHPDVTEAMLYEKFSPAGPVLSIRVCRDAvtrrslgY-AYVNFQQPADAERALDTLNFDVIKG 68

RNA recognition motif 1 (RRM1) found in the Hu proteins family, Drosophila sex-lethal (SXL), and similar proteins; This subfamily corresponds to the RRM1 of Hu proteins and SXL. The Hu proteins family represents a group of RNA-binding proteins involved in diverse biological processes. Since the Hu proteins share high homology with the Drosophila embryonic lethal abnormal vision (ELAV) protein, the Hu family is sometimes referred to as the ELAV family. Drosophila ELAV is exclusively expressed in neurons and is required for the correct differentiation and survival of neurons in flies. The neuronal members of the Hu family include Hu-antigen B (HuB or ELAV-2 or Hel-N1), Hu-antigen C (HuC or ELAV-3 or PLE21), and Hu-antigen D (HuD or ELAV-4), which play important roles in neuronal differentiation, plasticity and memory. HuB is also expressed in gonads. Hu-antigen R (HuR or ELAV-1 or HuA) is ubiquitously expressed Hu family member. It has a variety of biological functions mostly related to the regulation of cellular response to DNA damage and other types of stress. Hu proteins perform their cytoplasmic and nuclear molecular functions by coordinately regulating functionally related mRNAs. In the cytoplasm, Hu proteins recognize and bind to AU-rich RNA elements (AREs) in the 3' untranslated regions (UTRs) of certain target mRNAs, such as GAP-43, vascular epithelial growth factor (VEGF), the glucose transporter GLUT1, eotaxin and c-fos, and stabilize those ARE-containing mRNAs. They also bind and regulate the translation of some target mRNAs, such as neurofilament M, GLUT1, and p27. In the nucleus, Hu proteins function as regulators of polyadenylation and alternative splicing. Each Hu protein contains three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). RRM1 and RRM2 may cooperate in binding to an ARE. RRM3 may help to maintain the stability of the RNA-protein complex, and might also bind to poly(A) tails or be involved in protein-protein interactions. This family also includes the sex-lethal protein (SXL) from Drosophila melanogaster. SXL governs sexual differentiation and X chromosome dosage compensation in flies. It induces female-specific alternative splicing of the transformer (tra) pre-mRNA by binding to the tra uridine-rich polypyrimidine tract at the non-sex-specific 3' splice site during the sex-determination process. SXL binds to its own pre-mRNA and promotes female-specific alternative splicing. It contains an N-terminal Gly/Asn-rich domain that may be responsible for the protein-protein interaction, and tandem RRMs that show high preference to bind single-stranded, uridine-rich target RNA transcripts.

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gi 239050155 507 LVSSITGSKLYDLFKSVGNIHNVRVLPDR-----YC-AFVNYTSKDSCEKAIQMFNGHAIDGTTLVVRY 569
Cdd:cd12375    7 LPQSMTQEELRSLFGAIGPIESCKLVRDKitgqsLGyGFVNYRDPNDARKAINTLNGLDLENKRLKVSY 75

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.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 239050155 507 LVSSITGSKLYDLFKSVGNIHNVRVLPDRYC------AFVNYTSKDSCEKAIQMFNGHAIDGTTLVVRY 569
Cdd:cd12649    8 LPQDLTDREFRALFRAIGPVNTCKIVRDKKTgysygfGFVDFTSEEDAQRAIKTLNGLQLQNKRLKVAY 76

RNA recognition motif 3 (RRM3) found in heterogeneous nuclear ribonucleoprotein R (hnRNP R) and similar proteins; This subfamily corresponds to the RRM3 in hnRNP R, hnRNP Q, and APOBEC-1 complementation factor (ACF). hnRNP R is a ubiquitously expressed nuclear RNA-binding protein that specifically bind mRNAs with a preference for poly(U) stretches and has been implicated in mRNA processing and mRNA transport, and also acts as a regulator to modify binding to ribosomes and RNA translation. hnRNP Q is also a ubiquitously expressed nuclear RNA-binding protein. It has been identified as a component of the spliceosome complex, as well as a component of the apobec-1 editosome, and has been implicated in the regulation of specific mRNA transport. ACF is an RNA-binding subunit of a core complex that interacts with apoB mRNA to facilitate C to U RNA editing. It may also act as an apoB mRNA recognition factor and chaperone and play a key role in cell growth and differentiation. This family also includes two functionally unknown RNA-binding proteins, RBM46 and RBM47. All members contain three conserved RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains).

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDrYcAFVNYTSKDSCEKAIQMFNGHAIDGTTLVV 567
Cdd:cd12251    4 LYVRNLMLSTTEEKLRELFSEYGKVERVKKIKD-Y-AFVHFEERDDAVKAMEEMNGKELEGSEIEV 67

UBA domain found in proteins involved in ubiquitin-mediated proteolysis; The ubiquitin-associated (UBA) domains are commonly occurring sequence motifs found in proteins involved in ubiquitin-mediated proteolysis. They contribute to ubiquitin (Ub) binding or ubiquitin-like (UbL) domain binding. However, some kinds of UBA domains can only the bind UbL domain, but not the Ub domain. UBA domains are normally comprised of compact three-helix bundles which contain a conserved GF/Y-loop. They can bind polyubiquitin with high affinity. They also bind monoubiquitin and other proteins. Most UBA domain-containing proteins have one UBA domain, but some harbor two or three UBA domains.

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gi 239050155 413 QLMEMGFTKEQSSNALIIH-GTVERALE 439
Cdd:cd14270    3 QLVEMGFSREQARRALRATnGDVEAAVE 30

SGT1, suppressor of G2 allele of SKP1; Provisional

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 239050155 315 EMAVKYFTDAIKHNPKEYKLFGNRSYCYEKMLQYEKSLTDAEIALSMNPKWIKGLYRKGRALVGLKRYNEARLTF 389
Cdd:PLN03088  19 ALAVDLYTQAIDLDPNNAELYADRAQANIKLGNFTEAVADANKAIELDPSLAKAYLRKGTACMKLEEYQTAKAAL 93

RNA recognition motif 1 (RRM1) and 2 (RRM2) found in CELF/Bruno-like family of RNA binding proteins and plant flowering time control protein FCA; This subfamily corresponds to the RRM1 and RRM2 domains of the CUGBP1 and ETR-3-like factors (CELF) as well as plant flowering time control protein FCA. CELF, also termed BRUNOL (Bruno-like) proteins, is a family of structurally related RNA-binding proteins involved in regulation of pre-mRNA splicing in the nucleus, and control of mRNA translation and deadenylation in the cytoplasm. The family contains six members: CELF-1 (also known as BRUNOL-2, CUG-BP1, NAPOR, EDEN-BP), CELF-2 (also known as BRUNOL-3, ETR-3, CUG-BP2, NAPOR-2), CELF-3 (also known as BRUNOL-1, TNRC4, ETR-1, CAGH4, ER DA4), CELF-4 (BRUNOL-4), CELF-5 (BRUNOL-5) and CELF-6 (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. This subfamily also includes plant flowering time control protein FCA that functions in the posttranscriptional regulation of transcripts involved in the flowering process. FCA contains two RRMs, and a WW protein interaction domain.

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gi 239050155 499 LFpiwVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDRY------CAFVNYTSKDSCEKAIQMFNG-HAIDGTT--LVVR 568
Cdd:cd12361    2 LF---VGMIPKTASEEDVRPLFEQFGNIEEVQILRDKQtgqskgCAFVTFSTREEALRAIEALHNkKTMPGCSspLQVK 77

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

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gi 239050155 516 LYDLFKSVGNIHNVRVLPDRYC------AFVNYTSKDSCEKAIQMFNGHAIDGTTLVV 567
Cdd:cd12408   16 LRELFRPFGPISRVYLAKDKETgqskgfAFVTFETREDAERAIEKLNGFGYDNLILSV 73

RNA recognition motif 2 (RRM2) and 4 (RRM4) found in RNA-binding protein MRN1 and similar proteins; This subgroup corresponds to the RRM2 and RRM4 of MRN1, also termed multicopy suppressor of RSC-NHP6 synthetic lethality protein 1, or post-transcriptional regulator of 69 kDa, and is an RNA-binding protein found in yeast. Although its specific biological role remains unclear, MRN1 might be involved in translational regulation. Members in this family contain four copies of conserved RNA recognition motif (RRM), also known as RBD (RNA binding domain) or RNP (ribonucleoprotein domain).

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gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDRYCAFVNYTSKDSCEKAIQMFNGHAIDGTTLVVRY-PDR 572
Cdd:cd12262    6 VYVGNLDDSLTEEEIRGILEKYGEIESIKILKEKNCAFVNYLNIANAIKAVQELPIKNPKFKKVRINYgKDR 77

RNA recognition motif 3 (RRM3) found in Saccharomyces cerevisiae protein HRB1, G-strand-binding protein 2 (GBP2) and similar proteins; The family includes Saccharomyces cerevisiae protein HRB1 (also called protein TOM34) and GBP2, both of which are SR-like mRNA-binding proteins which shuttle from the nucleus to the cytoplasm when bound to the mature mRNA molecules. They act as quality control factors for spliced mRNAs. GBP2, also called RAP1 localization factor 6, is a single-strand telomeric DNA-binding protein that binds single-stranded telomeric sequences of the type (TG[1-3])n in vitro. It also binds to RNA. GBP2 influences the localization of RAP1 in the nuclei and plays a role in modulating telomere length. Members in this family contain three RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains). The model corresponds to the third RRM motif.

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gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDRY-----CAFVNYTSKDSCEKAIQMFNGHAIDGTTLVVRY 569
Cdd:cd21607    5 IYCSNLPLSTAESDLYDLFETIGKVNNAELKYDETgdptgSAVVEYENLDDADVCISKLNNYNYGGCDLKISY 77

RNA recognition motif 2 (RRM2) found in nucleolin-like proteins mainly from plants; This subfamily corresponds to the RRM2 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).

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gi 239050155 514 SKLYDLFKSVGNIHNVRVLPDRYC------AFVNYTSKDSCEKAIQMfNGHAIDGTTLVV 567
Cdd:cd12451   18 DELREHFGECGEVTNVRIPTDRETgelkgfAYIEFSTKEAKEKALEL-NGSDIAGGNLVV 76

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.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDRYC------AFVNYTSKDSCEKAIQMFNGHAIDGTTLVVRY 569
Cdd:cd12449    3 LFVGGLSFDTNEQSLEEVFSKYGQISEVVVVKDRETqrsrgfGFVTFENPDDAKDAMMAMNGKSLDGRQIRVDQ 76

RNA recognition motif 2 (RRM2) found in splicing regulatory glutamine/lysine-rich protein 1 (SREK1) and similar proteins; This subfamily corresponds to the RRM2 of SREK1, also termed serine/arginine-rich-splicing regulatory protein 86-kDa (SRrp86), or splicing factor arginine/serine-rich 12 (SFRS12), or splicing regulatory protein 508 amino acid (SRrp508). SREK1 belongs to a family of proteins containing regions rich in serine-arginine dipeptides (SR proteins family), which is involved in bridge-complex formation and splicing by mediating protein-protein interactions across either introns or exons. It is a unique SR family member and it may play a crucial role in determining tissue specific patterns of alternative splicing. SREK1 can alter splice site selection by both positively and negatively modulating the activity of other SR proteins. For instance, SREK1 can activate SRp20 and repress SC35 in a dose-dependent manner both in vitro and in vivo. In addition, SREK1 contains two (some contain only one) RNA recognition motifs (RRMs), also termed RBDs (RNA binding domains) or RNPs (ribonucleoprotein domains), and two serine-arginine (SR)-rich domains (SR domains) separated by an unusual glutamic acid-lysine (EK) rich region. The RRM and SR domains are highly conserved among other members of the SR superfamily. However, the EK domain is unique to SREK1. It plays a modulatory role controlling SR domain function by involvement in the inhibition of both constitutive and alternative splicing and in the selection of splice-site.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRV-----LPDRYcAFVNYTSKDSCEKAIQMfNGHAIDGTTLVV 567
Cdd:cd12260    7 VYVGNLDPSTTADQLLEFFSQAGEVKYVRMagdetQPTRY-AFVEFAEQTSVINALKL-NGKMFGGRPLKV 75

RNA recognition motif 1 (RRM1) found in yeast nuclear and cytoplasmic polyadenylated RNA-binding protein PUB1 and similar proteins; This subgroup corresponds to the RRM1 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.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPDR------YcAFVNYTSKDSCEKAIQMFNGHAIDGTTLVVRY 569
Cdd:cd12614    1 LYVGNLDPRVTEDLLQEIFAVTGPVENCKIIPDKnskgvnY-GFVEYYDRRSAEIAIQTLNGRQIFGQEIKVNW 73

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.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 239050155 502 IWVGDLVSSITGSKLYDLFKSVGNIHNVRVLPD-----RYCAFVNYTSKDSCEKAIQMFNGHAIDGTTLVV 567
Cdd:cd12381    4 LYVKNLDDTIDDEKLREEFSPFGTITSAKVMTDeggrsKGFGFVCFSSPEEATKAVTEMNGRIIGGKPLYV 74