MUTATION OF THE SPS1-ENCODED PROTEIN-KINASE OF SACCHAROMYCES-CEREVISIAE LEADS TO DEFECTS IN TRANSCRIPTION AND MORPHOLOGY DURING SPORE FORMATION
MUTATION OF THE SPS1-ENCODED PROTEIN-KINASE OF SACCHAROMYCES-CEREVISIAE LEADS TO DEFECTS IN TRANSCRIPTION AND MORPHOLOGY DURING SPORE FORMATION
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DOI：
10.1101/gad.8.18.2162
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发表时间：
1994-09-15
影响因子：
10.5
通讯作者：
SEGALL, J
中科院分区：
文献类型：
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作者：
FRIESEN, H;LUNZ, R;SEGALL, J
在酿酒酵母的孢子形成过程中，减数分裂之后是多层孢子壁内的单倍体核。完成孢子形成程序的晚期事件需要SPS 1基因。这种发育调节基因在细胞接近减数分裂结束时表达，编码与丝氨酸/苏氨酸蛋白激酶同源的蛋白质。Sps 1的催化结构域与酵母Ste 20的激酶结构域有44%相同，Ste 20是一种参与信息素诱导的信号转导途径的蛋白质。MATa/MAT α sps 1/sps 1菌株的细胞在减数分裂后停滞，并且不能激活通常在孢子形成后期表达的基因。通过相差显微镜评估，突变体细胞不形成无菌孢子，也不显示成熟孢子特有的天然荧光和耐乙醚性。然而，电子显微镜检查显示，在一些突变细胞中形成了类似原孢子的隔室。这些未成熟的孢子缺乏围绕野生型孢子的交联表面层，并且在大小和数量上比野生型细胞的孢子更易变。尽管它们不能完成孢子的形成，但sps 1被阻滞的细胞在转移到丰富培养基中时能够恢复有丝分裂生长，产生单倍体后代。我们的研究结果表明，发育调节Sps 1激酶是需要正常的转录，生化和形态学事件的进展，在孢子形成程序的后期部分。
During sporulation of Saccharomyces cerevisiae, meiosis is followed by encapsulation of haploid nuclei within multilayered spore walls. Completion of the late events of the sporulation program requires the SPS1 gene. This developmentally regulated gene, which is expressed as cells are nearing the end of meiosis, encodes a protein with homology to serine/threonine protein kinases. The catalytic domain of Sps1 is 44% identical to the kinase domain of yeast Ste20, a protein involved in the pheromone-induced signal transduction pathway. Cells of a MATa/MAT alpha sps1/sps1 strain arrest after meiosis and fail to activate genes that are normally expressed at a late time of sporulation. The mutant cells do not form refractile spores as assessed by phase-contrast microscopy and do not display the natural fluorescence and ether resistance that is characteristic of mature spores. Examination by electron microscopy reveals, however, that prospore-like compartments form in some of the mutant cells. These immature spores lack the cross-linked surface layer that surrounds wild-type spores and are more variable in size and number than are the spores of wild-type cells. Despite their inability to complete spore formation, sps1-arrested cells are able to resume mitotic growth on transfer to rich medium, generating haploid progeny. Our results suggest that the developmentally regulated Sps1 kinase is required for normal progression of transcriptional, biochemical, and morphological events during the later portion of the sporulation program.