Urushiyama S, Tani T, Ohshima Y
Department of Biology, Faculty of Science, Kyushu University, Fukuoka, Japan.
Mol Gen Genet. 1996 Nov 27;253(1-2):118-27. doi: 10.1007/s004380050304.
New prp (pre-mRNA processing) mutants of the fission yeast Schizosaccharomyces pombe were isolated from a bank of 700 mutants that were either temperature sensitive (ts-) or cold sensitive (cs-) for growth. The bank was screened by Northern blot analysis with probes complementary to S. pombe U6 small nuclear RNA (sn RNA), the gene for which has a splicesomal (mRNA-type) intron. We identified 12 prp mutants that accumulated the U6 snRNA precursor at the nonpermissive temperature. All such mutants were also found to have defects in an early step of TFIID pre-mRNA splicing at the nonpermissive temperature. Complementation analyses showed that seven of the mutants belong to six new complementation groups designated as prp8 and prp10-prp14, whereas the five other mutants were classified into the known complementation groups prp1, prp2 and prp3. Interestingly, some of the isolated prp mutants produced elongated cells at the nonpermissive temperature, which is a phenotype typical of cell division cycle (cdc) mutants. Based on these findings, we propose that some of the wild-type products from these prp+ genes play important roles in the cellular processes of pre-mRNA splicing and cell cycle progression.
从一组700个对生长表现出温度敏感（ts-）或冷敏感（cs-）的粟酒裂殖酵母突变体库中分离出了新的前体mRNA加工（prp）突变体。该突变体库通过用与粟酒裂殖酵母U6小核RNA（snRNA）互补的探针进行Northern印迹分析来筛选，U6 snRNA的基因含有一个剪接体（mRNA型）内含子。我们鉴定出12个prp突变体，它们在非允许温度下积累U6 snRNA前体。所有这些突变体在非允许温度下还被发现存在TFIID前体mRNA剪接早期步骤的缺陷。互补分析表明，其中7个突变体属于6个新的互补群，分别命名为prp8和prp10-prp14，而另外5个突变体被归类到已知的互补群prp1、prp2和prp3中。有趣的是，一些分离出的prp突变体在非允许温度下产生伸长的细胞，这是细胞分裂周期（cdc）突变体的典型表型。基于这些发现，我们提出这些prp+基因的一些野生型产物在mRNA前体剪接和细胞周期进程的细胞过程中发挥重要作用。
