Replication protein A, class 2b aminoacyl-tRNA synthetases, and related proteins with oligonucleotide/oligosaccharide (OB) fold.; This superfamily includes two oligonucleotide/oligosaccharide binding fold (OBF) domain families. One of these contains the OBF domains of the large (RPA1, 70kDa), middle (RPA2, RPA4, 32kDa) and small (RPA3, 14 kDa) subunits of human heterotrimeric Replication protein A (RPA), and similar domains. RPA is a nuclear single-strand (ss) DNA-binding protein involved in most aspects of DNA metabolism. This family includes the four OBF domains of RPA1 [DNA-binding domain (DBD)-A, DBD-B, DBD-C, and RPA1N], the OBF domain of RPA2 (RPA2 DBD-D), RPA3, and the OBF domain of RPA4. The major DNA binding activity of human RPA and Saccharomyces cerevisiae RPA appears to be associated with DBD-A and -B, of RPA1. RPA1 DBD-C shows only weak ssDNA-binding activity and is involved in trimerization. The other OBF domain family in this superfamily is the N-terminal, anticodon recognition domain of class 2b aminoacyl-tRNA synthetases (aaRSs). aaRSs catalyze the specific attachment of amino acids to their cognate tRNAs during protein biosynthesis. Class 2b aaRSs include the homodimeric aspartyl-, asparaginyl-, and lysyl-tRNA synthetases.

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gi 1831505893   1 MGKLKNVAGNKMILIYYLQKLADNKEYEIFKLETQASYL 39
Cdd:cd04478    57 FGNLKSFQGKKSIMAFSIRPVTDFNEVTYHLLEVIYVHL 95

RPA2_DBD_D: A subfamily of OB folds corresponding to the OB fold of the central ssDNA-binding domain (DBD)-D of human RPA2 (also called RPA32). RPA2 is a subunit of Replication protein A (RPA). RPA is a nuclear ssDNA-binding protein (SSB) which appears to be involved in all aspects of DNA metabolism including replication, recombination, and repair. RPA also mediates specific interactions of various nuclear proteins. In animals, plants, and fungi, RPA is a heterotrimer with subunits of 70KDa (RPA1), 32kDa (RPA2), and 14 KDa (RPA3). The major DNA binding activity of RPA is associated with RPA1 DBD-A and DBD-B; RPA2 DBD-D is a weak ssDNA-binding domain. RPA2 DBD-D is also involved in trimerization. The ssDNA binding mechanism is believed to be multistep and to involve conformational change. N-terminal to human RPA2 DBD-D is a domain containing all the known phosphorylation sites of RPA. Human RPA2 is phosphorylated in a cell cycle dependent manner in response to DNA damage. RPA2 interacts physically with menin; the gene encoding menin is a tumor suppressor gene disrupted in multiple endocrine neoplasia type I. This subfamily also includes RPA2 from Cryptosporidium parvum (CpRPA2). CpRPA2 is an SSB, which can be phosphorylated by DNA-PK in vitro.

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gi 1831505893   1 MGKLKNVAGNKMILIYYLQKLADNKEYEIFKLETQASYL 39
Cdd:cd04478    57 FGNLKSFQGKKSIMAFSIRPVTDFNEVTYHLLEVIYVHL 95

RPA2_DBD_D: A subfamily of OB folds corresponding to the OB fold of the central ssDNA-binding domain (DBD)-D of human RPA2 (also called RPA32). RPA2 is a subunit of Replication protein A (RPA). RPA is a nuclear ssDNA-binding protein (SSB) which appears to be involved in all aspects of DNA metabolism including replication, recombination, and repair. RPA also mediates specific interactions of various nuclear proteins. In animals, plants, and fungi, RPA is a heterotrimer with subunits of 70KDa (RPA1), 32kDa (RPA2), and 14 KDa (RPA3). The major DNA binding activity of RPA is associated with RPA1 DBD-A and DBD-B; RPA2 DBD-D is a weak ssDNA-binding domain. RPA2 DBD-D is also involved in trimerization. The ssDNA binding mechanism is believed to be multistep and to involve conformational change. N-terminal to human RPA2 DBD-D is a domain containing all the known phosphorylation sites of RPA. Human RPA2 is phosphorylated in a cell cycle dependent manner in response to DNA damage. RPA2 interacts physically with menin; the gene encoding menin is a tumor suppressor gene disrupted in multiple endocrine neoplasia type I. This subfamily also includes RPA2 from Cryptosporidium parvum (CpRPA2). CpRPA2 is an SSB, which can be phosphorylated by DNA-PK in vitro.

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gi 1831505893   1 MGKLKNVAGNKMILIYYLQKLADNKEYEIFKLETQASYL 39
Cdd:cd04478    57 FGNLKSFQGKKSIMAFSIRPVTDFNEVTYHLLEVIYVHL 95