| Primary Identifier | IPR045566 | Type | Domain |
| Short Name | SegE_GIY-YIG |
| description | This is a GIY-YIG domain mainly found in phages proteins, such as the Putative endonuclease segE from Bacteriophage T4. This domain is also found in some uncharacterised bacterial sequences. Proteins containing this domain are approximately 145-300 amino acids in length.Nucleases of the GIY-YIG family are involved in many cellular processes, including DNA repair and recombination, transfer of mobile genetic elements, and restriction of incoming foreign DNA. The GIY-YIG superfamily groups together nucleases characterised by the presence of a domain of typically ~100 amino acids, with two short motifs "GIY"and "YIG"in the N-terminal part, followed by an Arg residue in the centre and a Glu residue in the C-terminal part [, , , , ]. The GIY-YIG domain forms a compact structural domain, which serves as a scaffold for the coordination of a divalent metal ion required for catalysis of the phosphodiester bond cleavage. The GIY-YIG domain has an α/β-sandwich architecture with a central three-stranded antiparallel β-sheet flanked by three-helices. The three-stranded antiparallel β-sheet contains the GIY-YIG sequence elements. The most conserved and putative catalytic residues are located on a shallow, concave surface and include a metal coordination site [, , , ].The GIY-YIG domain has been implicated in a variety of cellular processes involving DNA cleavage, from self-propagation with or without introns, to restriction of foreign DNA, to DNA repair and maintenance of genome stability []. Some proteins known to contain a GIY-YIG domain include:Eukaryotic Slx-1 proteins, involved in the maintenance of the rDNA copy number. They have a C-terminal RING finger Zn-binding domain.Mammalian ankyrin repeat and LEM domain- containing protein 1 (ANKLE1).Bacterial and archaeal UvrC subunits of (A)BC excinucleases, which remove damaged nucleotides by incising the damaged strand on both sides of the lesion.Phage T4 endonucleases SegA to E, probably involved in the movement of the endonuclease-encoding DNA.Phage T4 intron-associated endonuclease 1 (I-TevI), specific to the thymidylate synthase (td) gene splice junction and involved in intron homing. |
