Wahls W P, Smith G R
Fred Hutchinson Cancer Research Center, Seattle, Washington 98104.
Genes Dev. 1994 Jul 15;8(14):1693-702. doi: 10.1101/gad.8.14.1693.
Homologous recombination hot spots are DNA sites that increase the frequency of recombination in their vicinity. The M26 allele of the ade6 gene in Schizosaccharomyces pombe is the first meiotic hot spot with an identified unique nucleotide sequence. We have purified 40,000-fold a heteromeric protein, containing polypeptides Mts1 (70 kD) and Mts2 (28 kD), that binds to the M26 site. Binding in vitro strictly correlates with hot spot activity in vivo for numerous single base pair substitutions in the vicinity of the M26 site, indicating that Mts1/Mts2 activates the M26 site and promotes a rate-limiting step of meiotic recombination. These and other data suggest that homologous recombination may be regulated primarily by discrete DNA sites and proteins that interact with those sites.
同源重组热点是指能增加其附近区域重组频率的DNA位点。粟酒裂殖酵母中ade6基因的M26等位基因是首个具有已确定独特核苷酸序列的减数分裂热点。我们已将一种异源蛋白纯化了40000倍，该蛋白包含与M26位点结合的多肽Mts1（70kD）和Mts2（28kD）。对于M26位点附近的众多单碱基对替换，体外结合与体内热点活性严格相关，这表明Mts1/Mts2激活M26位点并促进减数分裂重组的限速步骤。这些以及其他数据表明，同源重组可能主要由离散的DNA位点和与这些位点相互作用的蛋白质调控。
