Construction of a mini-chromosome by deletion and its mitotic and meiotic behaviour in fission yeast-猫眼课题宝

裂殖酵母中缺失微型染色体的构建及其有丝分裂和减数分裂行为

DOI：

发表时间：

1986

期刊：

Molecular and General Genetics MGG

影响因子：

通讯作者：

中科院分区：

文献类型：

作者：

O. Niwa;Tomohiro Matsumoto;M. Yanagida

本研究利用γ射线诱变裂殖酵母裂殖酵母（Schizosophylomycespombe）的不稳定非整倍体二体，获得了一株高度稳定的部分非整倍体菌株HM 248。它含有一个500 kb的小染色体（命名为Ch 16），通过脉冲场梯度电泳分离为单一条带。遗传分析表明，Ch 16被删除的大部分染色体III除了臂间区，三个着丝粒连锁标记，包括着丝粒区域仍然存在。这进一步证实了整合的克隆片段的Ch 16 DNA提取的琼脂糖凝胶;整合发生在臂间区。构建了一个400 kb的衍生物（Ch 16 D1），它似乎缺乏Ch 16的一部分。S.粟酒裂殖酵母除保持3条常规染色体外，还能稳定保持Ch 16和Ch 16 D1。在限制性条件下，Ch 16在β-微管蛋白突变体的细胞核中被可视化为微小的染色体体。单拷贝Ch 16在有丝分裂和减数分裂过程中表现得像一条天然染色体，具有高度稳定性。染色体丢失的频率为10-4。在减数分裂中，它独立于常规染色体III分离。通过特异性标记含有氟尿嘧啶抗性标记物（Ch 16 FR）的酿酒酵母LEU 2基因（命名为Ch 16 LE）的Ch 16，可以监测每个细胞中两个Ch 16的分离。两个拷贝的Ch 16是有丝分裂不稳定的（染色体丢失，10-3），经常失败的减数分裂分离。两个Ch 16之间的减数分裂重组的频率大大降低。

SummaryA highly stable, partial aneuploid, HM248, of the fission yeast Schizosaccharomyces pombe was obtained from the unstable aneuploid disomic for chromosome III by γ-irradiation. It contained a 500 kb mini-chromosome (designated Ch16) that was separated as a single band by pulsed field gradient electrophoresis. Genetic analysis showed that Ch16 was deleted for most of chromosome III except for the pericentric region; three centromere-linked markers encompassing the centromere region remained. This was further substantiated by integrating the cloned fragments of Ch16 DNA extracted from the agarose gel; integrations took place in the pericentric region. A 400 kb derivative (Ch16D1) was constructed which appeared to lack a part of Ch16. A single haploid cell of S. pombe could stably maintain Ch16 and Ch16D1 in addition to the three regular chromosomes. Ch16 was visualized as a minute chromosomal body in the nucleus of a β-tubulin mutant under restrictive conditions. A single copy of Ch16 was highly stable and behaved like a natural chromosome in mitosis and meiosis. The frequency of chromosomal loss was 10-4. In meiosis, it segregated independently of the regular chromosome III. Segregation of two Ch16s per cell could be monitored by specifically marked Ch16s containing the Saccharomyces cerevisiae LEU2 gene (designated Ch16LE) of the fluorouracil resistance marker (Ch16FR). Two copies of Ch16 were mitotically unstable (chromosomal loss, 10-3) and frequently failed in meiotic segregation. The frequency of meiotic recombination between the two Ch16s was greatly reduced.

Construction of telocentric chromosomes in Saccharomyces cerevisiae.