"Break copy" duplication: a model for chromosome fragment formation in Saccharomyces cerevisiae.
"Break copy" duplication: a model for chromosome fragment formation in Saccharomyces cerevisiae.
复制标题
“断裂复制”复制：酿酒酵母染色体片段形成的模型。
DOI：
10.1093/genetics/147.2.371
复制
发表时间：
1997
期刊：
影响因子：
3.3
通讯作者：
Hieter,P
中科院分区：
文献类型：
--
作者：
Morrow,DM;Connelly,C;Hieter,P
将染色体碎裂载体(CFV)导入芽殖酵母酿酒酵母产生定向同源重组事件，产生独立分离的染色体片段(CF)并改变菌株的核型。用着丝粒-近端定向的无着丝粒CFV进行碎片化会产生一个包含靶向片段附近所有序列的CF，并导致内源靶向染色体的丢失，从而产生2N-1+CF核型。相反，用着丝粒-远端定向的中心性CFV进行碎片化会产生一种CF，它包含靶向片段远端的所有序列，并保留内源靶向染色体，从而产生2N+CF核型。我们把这种现象称为“断拷贝”复制。用着丝粒转座到新位置的酵母菌株，证明着丝粒抑制了断裂复制。这些数据表明，CFV的形成是由CFV的自由端启动的非计划DNA复制事件的产物，类似于“半”双链断裂缺口修复反应。我们认为，在DNA断裂后，断裂复制可能已经进化为一种维持倍性的机制。
Introduction of a chromosome fragmentation vector (CFV) into the budding yeastSaccharomyces cerevisiaeresults in a targeted homologous recombination event that yields an independently segregating chromosome fragment (CF) and an alteration in the strain's karyotype. Fragmentation with an acentric CFV directed in a centromere-proximal orientation generates a CF that contains all sequences proximal to the targeting segment and results in loss of the endogenous targeted chromosome to yield a 2N-1+CF karyotype. In contrast, fragmentation with a centric CFV directed in a centromere-distal orientation generates a CF that contains all sequences distal to the targeting segment and retention of the endogenous targeted chromosome to yield a 2N+CF karyotype. We have termed this phenomenon “break copy” duplication. Using yeast strains in which the centromere had been transposed to a new location, it was demonstrated that the centromere inhibited break copy duplication. These data suggest that CF formation is the product of an unscheduled DNA replication event initiated by the free end of the CFV and is analogous to a “half” double-strand break gap-repair reaction. We suggest that break copy duplication may have evolved as a mechanism for maintenance of ploidy following DNA breakage.