Allshire R C, Cranston G, Gosden J R, Maule J C, Hastie N D, Fantes P A
Cell. 1987 Jul 31;50(3):391-403. doi: 10.1016/0092-8674(87)90493-4.
To test the functional capacity of a fission yeast chromosome in mouse cells, a strain of the fission yeast Schizosaccharomyces pombe, ED628 Int5, was constructed. A plasmid bearing the SV2NEO gene, which can confer G418 resistance to mouse cells, was integrated at the ura4 locus on S. pombe chromosome III. S. pombe Int5 chromosomes were introduced into mouse C127 cells by PEG-facilitated protoplast fusion. Here we describe two independent G418-resistant cell lines with distinct growth characteristics, F1.1 and F7.1, and examine the structure of material derived from S. pombe Int5 chromosome III in these lines. F1.1 is shown to contain a single rearranged block of chromatin from S. pombe chromosome III integrated into a mouse chromosome, maintained in the absence of selection. In contrast, the data for F7.1 are consistent with the presence of linear, unintegrated copies of S. pombe chromosome III, which are apparently intact and maintained in an unstable but autonomous state. The unstable maintenance of this chromosome may be due to defective centromere function leading to missegregation at mitosis or to over- or underreplication.
为了测试裂殖酵母染色体在小鼠细胞中的功能能力，构建了一株裂殖酵母粟酒裂殖酵母（Schizosaccharomyces pombe），即ED628 Int5。携带SV2NEO基因（可赋予小鼠细胞对G418的抗性）的质粒整合到粟酒裂殖酵母III号染色体的ura4位点。通过聚乙二醇介导的原生质体融合将粟酒裂殖酵母Int5染色体导入小鼠C127细胞。在此，我们描述了两个具有不同生长特性的独立G418抗性细胞系F1.1和F7.1，并研究了这些细胞系中源自粟酒裂殖酵母Int5 III号染色体的物质结构。结果显示F1.1含有一个来自粟酒裂殖酵母III号染色体的单一重排染色质块，整合到小鼠染色体中，在无选择条件下得以维持。相比之下，F7.1的数据表明存在粟酒裂殖酵母III号染色体的线性、未整合拷贝，这些拷贝显然完整，并以不稳定但自主的状态维持。该染色体的不稳定维持可能是由于着丝粒功能缺陷导致有丝分裂时的错误分离，或者是由于复制过度或不足。
