Coordination of the initiation of recombination and the reductional division in meiosis in Saccharomyces cerevisiae.
Coordination of the initiation of recombination and the reductional division in meiosis in Saccharomyces cerevisiae.
复制标题
酿酒酵母减数分裂重组启动和减数分裂的协调。
DOI：
10.1093/genetics/152.1.117
复制
发表时间：
1999
期刊：
影响因子：
3.3
通讯作者：
Malone,RE
中科院分区：
文献类型：
--
作者：
Jiao,K;Bullard,SA;Salem,L;Malone,RE
早期交换(EE)基因是启动酿酒酵母减数分裂重组所必需的。具有几个EE基因突变的细胞经历较早的还原分裂(MI)，这表明减数分裂重组的启动参与了确定适当的分裂时机。零突变对减数分裂时机的不同影响使EE基因可分为三类：RAD50或REC102突变导致非常早的减数分裂；REC104或REC114突变导致比野生型(WT)细胞早分裂，但晚于第一类突变体；以及MEI4突变不显著改变MI的分裂时间。非常早期的突变是其他两类突变的上位性突变。我们提出了一个模型，解释了重组启动和第一次分裂之间的上位关系和沟通。本文中的数据表明，双链断裂(DSB)不是还原分裂正常延迟的信号；这些实验也证实了MEI4是减数分裂DSB形成所必需的。最后，如果DSB是由HO内切酶提供的，则在没有MEI4和REC104的情况下可以发生重组。
Early exchange (EE) genes are required for the initiation of meiotic recombination in Saccharomyces cerevisiae. Cells with mutations in several EE genes undergo an earlier reductional division (MI), which suggests that the initiation of meiotic recombination is involved in determining proper timing of the division. The different effects of null mutations on the timing of reductional division allow EE genes to be assorted into three classes: mutations in RAD50 or REC102 that confer a very early reductional division; mutations in REC104 or REC114 that confer a division earlier than that of wild-type (WT) cells, but later than that of mutants of the first class; and mutations in MEI4 that do not significantly alter the timing of MI. The very early mutations are epistatic to mutations in the other two classes. We propose a model that accounts for the epistatic relationships and the communication between recombination initiation and the first division. Data in this article indicate that double-strand breaks (DSBs) are not the signal for the normal delay of reductional division; these experiments also confirm that MEI4 is required for the formation of meiotic DSBs. Finally, if a DSB is provided by the HO endonuclease, recombination can occur in the absence of MEI4 and REC104.