Loidl J, Klein F, Scherthan H
Department of Cytology and Genetics, University of Vienna, Austria.
J Cell Biol. 1994 Jun;125(6):1191-200. doi: 10.1083/jcb.125.6.1191.
In situ hybridization was used to examine chromosome behavior at meiotic prophase in the rad50S, hop1, rad50, and spo11 mutants of Saccharomyces cerevisiae, which are defective in chromosome synapsis and meiotic recombination. Painting of chromosomes I and III revealed that chromosome condensation and pairing are reduced in these mutants. However, there is some residual pairing in meiosis, suggesting that homologue recognition is independent of synaptonemal complex formation and recombination. Association of homologues was observed in the rad50, rad50S, and spo11 mutants, which are defective in the formation or processing of meiotic double-strand breaks. This indicates that double-strand breaks are not an essential component of the meiotic homology searching mechanism or that there exist additional or alternative mechanisms for locating homologues.
原位杂交技术用于检测酿酒酵母的rad50S、hop1、rad50和spo11突变体减数分裂前期的染色体行为,这些突变体在染色体联会和减数分裂重组方面存在缺陷。对I号和III号染色体的染色显示,这些突变体中染色体的凝聚和配对减少。然而,减数分裂中仍存在一些残余配对,这表明同源物识别独立于联会复合体的形成和重组。在rad50、rad50S和spo11突变体中观察到同源物的关联,这些突变体在减数分裂双链断裂的形成或加工方面存在缺陷。这表明双链断裂不是减数分裂同源性搜索机制的必要组成部分,或者存在其他定位同源物的机制或替代机制。