The GIY-YIG domain of uncharacterized protein family UPF0213 related to structure-specific endonuclease SLX1; This family contains a group of uncharacterized proteins found mainly in bacteria and several in dsDNA viruses. Although their function roles have not been recognized, these proteins show significant sequence similarities with the N-terminal GIY-YIG endonuclease domain of structure-specific endonuclease subunit SLX1, which binds another structure-specific endonuclease subunit SLX4 to form an active heterodimeric SLX1-SLX4 complex. This complex functions as a 5' flap endonuclease in yeast, and has also been identified as a Holliday junction resolvase in human.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 446336488  6 HCFYVVECSDGSYYAGYTNHIEKRIQTHNSGKGARYTRARLPVVLKYIEFHEDKRTAMQAEYYFKQL 72
Cdd:cd10456   1 WYVYILRCADGSLYTGITTDLERRLAEHNSGKGAKYTRGRRPVKLVYSEEFDDRSEALKREYRIKKL 67

GIY-YIG catalytic domain; This domain called GIY-YIG is found in the amino terminal region of excinuclease abc subunit c (uvrC), bacteriophage T4 endonucleases segA, segB, segC, segD and segE; it is also found in putative endonucleases encoded by group I introns of fungi and phage. The structure of I-TevI a GIY-YIG endonuclease, reveals a novel alpha/beta-fold with a central three-stranded antiparallel beta-sheet flanked by three helices. The most conserved and putative catalytic residues are located on a shallow, concave surface and include a metal coordination site.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 446336488   5 KHCFYVVECSDGS-YYAGYTNHIEKRIQTHNSGKGARYTRARL--PVVLKYIEFHEDKRTAMQAEYYFKQLNRKQKE 78
Cdd:pfam01541  1 KGGIYIIRNKDNKlLYVGSTKNLERRLNQHNAGKGAKYTRGKGvePFKLIYLEEFPTKSEALELEKYLIKLYRPNKY 77

The GIY-YIG domain of uncharacterized protein family UPF0213 related to structure-specific endonuclease SLX1; This family contains a group of uncharacterized proteins found mainly in bacteria and several in dsDNA viruses. Although their function roles have not been recognized, these proteins show significant sequence similarities with the N-terminal GIY-YIG endonuclease domain of structure-specific endonuclease subunit SLX1, which binds another structure-specific endonuclease subunit SLX4 to form an active heterodimeric SLX1-SLX4 complex. This complex functions as a 5' flap endonuclease in yeast, and has also been identified as a Holliday junction resolvase in human.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 446336488  6 HCFYVVECSDGSYYAGYTNHIEKRIQTHNSGKGARYTRARLPVVLKYIEFHEDKRTAMQAEYYFKQL 72
Cdd:cd10456   1 WYVYILRCADGSLYTGITTDLERRLAEHNSGKGAKYTRGRRPVKLVYSEEFDDRSEALKREYRIKKL 67

GIY-YIG catalytic domain; This domain called GIY-YIG is found in the amino terminal region of excinuclease abc subunit c (uvrC), bacteriophage T4 endonucleases segA, segB, segC, segD and segE; it is also found in putative endonucleases encoded by group I introns of fungi and phage. The structure of I-TevI a GIY-YIG endonuclease, reveals a novel alpha/beta-fold with a central three-stranded antiparallel beta-sheet flanked by three helices. The most conserved and putative catalytic residues are located on a shallow, concave surface and include a metal coordination site.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 446336488   5 KHCFYVVECSDGS-YYAGYTNHIEKRIQTHNSGKGARYTRARL--PVVLKYIEFHEDKRTAMQAEYYFKQLNRKQKE 78
Cdd:pfam01541  1 KGGIYIIRNKDNKlLYVGSTKNLERRLNQHNAGKGAKYTRGKGvePFKLIYLEEFPTKSEALELEKYLIKLYRPNKY 77

Catalytic GIY-YIG domain of yeast structure-specific endonuclease subunit SLX1 and its eukaryotic homologs; Structure-specific endonuclease subunit SLX1 is a highly conserved protein from yeast to human, with an N-terminal GIY-YIG endonuclease domain and a C-terminal PHD-type zinc finger postulated to mediate protein-protein or protein-DNA interaction. SLX1 forms active heterodimeric complexes with its SLX4 partner, which has additional roles in the DNA damage response that are distinct from the function of the heterodimeric SLX1-SLX4 nuclease. In yeast, the SLX1-SLX4 complex functions as a 5' flap endonuclease that maintains ribosomal DNA copy number, where SLX1 and SLX4 are shown to be catalytic and regulatory subunits, respectively. This endonuclease introduces single-strand cuts in duplex DNA on the 3' side of junctions with single-strand DNA. In addition to 5' flap endonuclease activity, human SLX1-SLX4 complex has been identified as a Holliday junction resolvase that promotes symmetrical cleavage of static and migrating Holliday junctions. SLX1 also associates with MUS81, EME1, C20orf94, PLK1, and ERCC1. Some eukaryotic SLX1 homologs lack the zinc finger domain, but possess intrinsically unstructured extensions of unknown function. These unstructured segments might be involved in interactions with other proteins.

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gi 446336488  6 HCFYVVECSDGSY----YAGYTNHIEKRIQTHNSG--KGARYTRARLP 47
Cdd:cd10455   2 YGVYLLRSLNPKYkgrtYIGFTVNPPRRLRQHNGElkGGAKKTSRKRP 49

GIY-YIG nuclease domain superfamily; The GIY-YIG nuclease domain superfamily includes a large and diverse group of proteins involved in many cellular processes, such as class I homing GIY-YIG family endonucleases, prokaryotic nucleotide excision repair proteins UvrC and Cho, type II restriction enzymes, the endonuclease/reverse transcriptase of eukaryotic retrotransposable elements, and a family of eukaryotic enzymes that repair stalled replication forks. All of these members contain a conserved GIY-YIG nuclease domain that may serve as a scaffold for the coordination of a divalent metal ion required for catalysis of the phosphodiester bond cleavage. By combining with different specificity, targeting, or other domains, the GIY-YIG nucleases may perform different functions.

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gi 446336488  9 YVVECSD-GSYYAGYTNHIEKRIQTHNSGKGARYTRARLPVVLKYIEFHE-DKRTAMQAEYYFKQL 72
Cdd:cd00719   3 YVLYDEDnGLIYVGQTKNLRNRIKEHLRKQRSDWTKGLKPFEILYLEVAPeAESELLDLEAALIKK 68