Hotspots of homologous recombination |
| |
Authors: | G R Smith |
| |
Institution: | (1) Fred Hutchinson Cancer Research Center, 1124 Columbia St., 98104 Seattle, Washington, USA |
| |
Abstract: | Homologous recombination occurs at higher than average frequency at and near hotspots. Hotspots are special nucleotide sequences recognized by proteins that promote, directly or indirectly, a rate limiting step of recombination. This review focuses on two well-studied examples, the Chi sites of the bacteriumEscherichia coli and the M26 site of the fission yeastSchizosaccharomyces pombe. Chi, 5 G-C-T-G-G-T-G-G 3 , is recognized by the RecBCD enzyme, which nicks the DNA near Chi and produces a 3 -ended single-stranded DNA tail ; this tail is a potent substrate for homologous pairing by RecA and single-stranded DNA binding proteins. M26, 5 A-T-G-A-C-G-T 3 , is recognized by a heterodimeric protein and stimulates, by an as-yet-unknown mechanism, meiotic recombination at and near theade6 gene. Additional hotspots in bacteria, fungi, and mammals enhance recombination directly or indirectly via a variety of mechanisms. Although hotspots are widespread among organisms, the biological role of their localized enhancement of recombination remains a matter of speculation. |
| |
Keywords: | Homologous recombination hotspots nucleases meiosis Escherichia coli Chi Schizosaccharomyces pombe M26 |
本文献已被 SpringerLink 等数据库收录! |
|