Ribonuclease H2-B is a subunit of the eukaryotic RNase H complex which cleaves RNA-DNA hybrids; Ribonuclease H2B is one of the three proteins of eukaryotic RNase H2 complex that is required for nucleic acid binding and hydrolysis. RNase H is classified into two families, type I (prokaryotic RNase HI, eukaryotic RNase H1 and viral RNase H) and type II (prokaryotic RNase HII and HIII, and eukaryotic RNase H2/HII). RNase H endonucleolytically hydrolyzes an RNA strand when it is annealed to a complementary DNA strand in the presence of divalent cations, in DNA replication and repair. The enzyme can be found in bacteria, archaea, and eukaryotes. Most prokaryotic and eukaryotic genomes contain multiple RNase H genes. Despite a lack of evidence for homology from sequence comparisons, type I and type II RNase H share a common fold and similar steric configurations of the four acidic active-site residues, suggesting identical or very similar catalytic mechanisms. Eukaryotic RNase HII is active during replication and is believed to play a role in removal of Okazaki fragment primers and single ribonucleotides in DNA-DNA duplexes. Eukaryotic RNase HII is functional when it forms a complex with RNase H2B and RNase H2C proteins. It is speculated that the two accessory subunits are required for correct folding of the catalytic subunit of RNase HII. Mutations in the three subunits of human RNase HII cause neurological disorder.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672078342  30 KSKSGLLFVKLVNPHSGEGATYLIDACLQkLFEIKVFKE--KHHSWFI-NQSVQSGGLLHFATPMDPLFLLLHYLIKAGK 106
Cdd:cd09270    9 TDESQLRIVTLPHPRTGKPTRYLFCPDGQ-LYELTAFKEskAPRSWFIgNGTVLQDGSLYVATPFDPLFLLLPILYKADN 87

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 672078342 107 E--GKYQPLDQVVVDDKFPDCTLL--LRFPELEKSLRHVTEEKEVNSKKYYKYSTEKTLKWLEKKVNQT 171
Cdd:cd09270   88 KfaGKFLTLDDILDDLSSPSSHLLedLPLPILESSLAKICDVKEEGDDKFYKYSDEKLLAWLLKKVERL 156

Ribonuclease H2-B is a subunit of the eukaryotic RNase H complex which cleaves RNA-DNA hybrids; Ribonuclease H2B is one of the three proteins of eukaryotic RNase H2 complex that is required for nucleic acid binding and hydrolysis. RNase H is classified into two families, type I (prokaryotic RNase HI, eukaryotic RNase H1 and viral RNase H) and type II (prokaryotic RNase HII and HIII, and eukaryotic RNase H2/HII). RNase H endonucleolytically hydrolyzes an RNA strand when it is annealed to a complementary DNA strand in the presence of divalent cations, in DNA replication and repair. The enzyme can be found in bacteria, archaea, and eukaryotes. Most prokaryotic and eukaryotic genomes contain multiple RNase H genes. Despite a lack of evidence for homology from sequence comparisons, type I and type II RNase H share a common fold and similar steric configurations of the four acidic active-site residues, suggesting identical or very similar catalytic mechanisms. Eukaryotic RNase HII is active during replication and is believed to play a role in removal of Okazaki fragment primers and single ribonucleotides in DNA-DNA duplexes. Eukaryotic RNase HII is functional when it forms a complex with RNase H2B and RNase H2C proteins. It is speculated that the two accessory subunits are required for correct folding of the catalytic subunit of RNase HII. Mutations in the three subunits of human RNase HII cause neurological disorder.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672078342  30 KSKSGLLFVKLVNPHSGEGATYLIDACLQkLFEIKVFKE--KHHSWFI-NQSVQSGGLLHFATPMDPLFLLLHYLIKAGK 106
Cdd:cd09270    9 TDESQLRIVTLPHPRTGKPTRYLFCPDGQ-LYELTAFKEskAPRSWFIgNGTVLQDGSLYVATPFDPLFLLLPILYKADN 87

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 672078342 107 E--GKYQPLDQVVVDDKFPDCTLL--LRFPELEKSLRHVTEEKEVNSKKYYKYSTEKTLKWLEKKVNQT 171
Cdd:cd09270   88 KfaGKFLTLDDILDDLSSPSSHLLedLPLPILESSLAKICDVKEEGDDKFYKYSDEKLLAWLLKKVERL 156

Ribonuclease H2-B is a subunit of the eukaryotic RNase H complex which cleaves RNA-DNA hybrids; Ribonuclease H2B is one of the three proteins of eukaryotic RNase H2 complex that is required for nucleic acid binding and hydrolysis. RNase H is classified into two families, type I (prokaryotic RNase HI, eukaryotic RNase H1 and viral RNase H) and type II (prokaryotic RNase HII and HIII, and eukaryotic RNase H2/HII). RNase H endonucleolytically hydrolyzes an RNA strand when it is annealed to a complementary DNA strand in the presence of divalent cations, in DNA replication and repair. The enzyme can be found in bacteria, archaea, and eukaryotes. Most prokaryotic and eukaryotic genomes contain multiple RNase H genes. Despite a lack of evidence for homology from sequence comparisons, type I and type II RNase H share a common fold and similar steric configurations of the four acidic active-site residues, suggesting identical or very similar catalytic mechanisms. Eukaryotic RNase HII is active during replication and is believed to play a role in removal of Okazaki fragment primers and single ribonucleotides in DNA-DNA duplexes. Eukaryotic RNase HII is functional when it forms a complex with RNase H2B and RNase H2C proteins. It is speculated that the two accessory subunits are required for correct folding of the catalytic subunit of RNase HII. Mutations in the three subunits of human RNase HII cause neurological disorder.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 672078342  30 KSKSGLLFVKLVNPHSGEGATYLIDACLQkLFEIKVFKE--KHHSWFI-NQSVQSGGLLHFATPMDPLFLLLHYLIKAGK 106
Cdd:cd09270    9 TDESQLRIVTLPHPRTGKPTRYLFCPDGQ-LYELTAFKEskAPRSWFIgNGTVLQDGSLYVATPFDPLFLLLPILYKADN 87

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 672078342 107 E--GKYQPLDQVVVDDKFPDCTLL--LRFPELEKSLRHVTEEKEVNSKKYYKYSTEKTLKWLEKKVNQT 171
Cdd:cd09270   88 KfaGKFLTLDDILDDLSSPSSHLLedLPLPILESSLAKICDVKEEGDDKFYKYSDEKLLAWLLKKVERL 156

Ydr279p protein triple barrel domain; RNases H are enzymes that specifically hydrolyse RNA when annealed to a complementary DNA and are present in all living organizms. In yeast RNase H2 is composed of a complex of three proteins (Rnh2Ap, Ydr279p and Ylr154p), this family represents the homologs of Ydr279p. It is not known whether non yeast proteins in this family fulfil the same function. This domain corresponds to the N-terminal triple barrel domain.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 672078342   37 FVKLVNPHSGEGATYLIDACLQKLFEIKVF---KEKHHSWFI-------NQSVQSGGLLHFATPMD 92
Cdd:pfam17745   1 IVTLPHPRTGSPSRYLLCPETGQLYEFTKIaapKETPRSWLIenendrsDGYVLKDGELLVATPID 66