Evans D H, Li Y F, Fox M E, Smith G R
Fred Hutchinson Cancer Research Center, Seattle, Washington 98104, USA.
Genetics. 1997 Aug;146(4):1253-64. doi: 10.1093/genetics/146.4.1253.
Mutations in the Schizosaccharomyces pombe rec14 gene reduce meiotic recombination by as much as a factor of 1000 in the three intervals tested on chromosomes I and III. A DNA clone complementing the rec14 mutation was shown by genetic and physical analysis to contain the rec14 gene, which was functional in plasmid-borne inserts as small as 1.4 kb. The rec14 gene contains two exons separated by a 53-bp intron, which was confirmed by analysis of rec14 transcripts. The spliced transcript encodes a protein product of 302 amino acids, which contains six WD repeat motifs found in the G-beta transducin family of proteins and other proteins, including the Saccharomyces cerevisiae Ski8 (Rec103) protein. Although the rec14 transcripts were present in mitotically dividing cells, rec14 mutations had no detectable effect on mitotic recombination. The pattern of expression of rec14 differes from that of previously analyzed S. pombe rec genes. Based upon mutant phenotypes and amino acid sequence similarities, we propose that S. pombe Rec14 is a functional homologue of S. cerevisiae Rec103.
粟酒裂殖酵母rec14基因的突变在对I号和III号染色体上所测试的三个区间内,使减数分裂重组减少多达1000倍。通过遗传和物理分析表明,一个能够互补rec14突变的DNA克隆含有rec14基因,该基因在小至1.4 kb的质粒插入片段中具有功能。rec14基因包含两个由一个53 bp内含子隔开的外显子,这通过对rec14转录本的分析得到证实。剪接后的转录本编码一个302个氨基酸的蛋白质产物,该产物含有在G-β转导蛋白家族以及包括酿酒酵母Ski8(Rec103)蛋白在内的其他蛋白质中发现的六个WD重复基序。尽管rec14转录本存在于有丝分裂细胞中,但rec14突变对有丝分裂重组没有可检测到的影响。rec14的表达模式与先前分析的粟酒裂殖酵母rec基因的表达模式不同。基于突变体表型和氨基酸序列相似性,我们提出粟酒裂殖酵母Rec14是酿酒酵母Rec103的功能同源物。