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 1102618193   2 YYLYRHIRLDKNEVFYIGIGTvpktnynissiktyYNRAFEKVKSRNKYWKNITNITDYLVEI 64
Cdd:cd10440     1 YYVYALIDPRTGEVFYVGKGK--------------GNRVFSHVKEALGEYENIKEKLSAKLQR 49

GIY-YIG domain of uncharacterized proteins from bacteria and their eukaryotic homologs; This family includes a group of functionally uncharacterized proteins from bacteria and their eukaryotic homologs which are present only in metazoa. These proteins might have nuclease activities and possibly be engaged in DNA repair or recombination, since they share sequence homology with the catalytic GIY-YIG domain of bacterial UvrC DNA repair proteins. Distinct from their prokaryotic relatives, the eukaryotic homologs contain an N-terminal extension that includes the region of approximately 3-4 ankyrin repeats, unique motifs mediating protein-protein interactions. Some of eukaryotic homologs do have an additional LEM domain located between ankyrin repeats region and GIY-YIG domain. The LEM domain, found in inner nuclear membrane proteins, may be involved in protein- or DNA-binding. The different domain composition of the eukaryotic homologs suggests that they might participate in interactions with multiple partners and implies important cellular function.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1102618193   2 YYLYRHIRLDKNEVFYIGIGTvpktnynissiktyYNRAFEKVKSRNKYWKNITNITDYLVEI 64
Cdd:cd10440     1 YYVYALIDPRTGEVFYVGKGK--------------GNRVFSHVKEALGEYENIKEKLSAKLQR 49

GIY-YIG domain of uncharacterized proteins from bacteria and their eukaryotic homologs; This family includes a group of functionally uncharacterized proteins from bacteria and their eukaryotic homologs which are present only in metazoa. These proteins might have nuclease activities and possibly be engaged in DNA repair or recombination, since they share sequence homology with the catalytic GIY-YIG domain of bacterial UvrC DNA repair proteins. Distinct from their prokaryotic relatives, the eukaryotic homologs contain an N-terminal extension that includes the region of approximately 3-4 ankyrin repeats, unique motifs mediating protein-protein interactions. Some of eukaryotic homologs do have an additional LEM domain located between ankyrin repeats region and GIY-YIG domain. The LEM domain, found in inner nuclear membrane proteins, may be involved in protein- or DNA-binding. The different domain composition of the eukaryotic homologs suggests that they might participate in interactions with multiple partners and implies important cellular function.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1102618193   2 YYLYRHIRLDKNEVFYIGIGTvpktnynissiktyYNRAFEKVKSRNKYWKNITNITDYLVEI 64
Cdd:cd10440     1 YYVYALIDPRTGEVFYVGKGK--------------GNRVFSHVKEALGEYENIKEKLSAKLQR 49