Characterization of genes required for protein sorting and vacuolar function in the yeast Saccharomyces cerevisiae.
Characterization of genes required for protein sorting and vacuolar function in the yeast Saccharomyces cerevisiae.
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DOI：
10.1002/j.1460-2075.1989.tb03614.x
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发表时间：
1989-07
期刊：
影响因子：
--
通讯作者：
J. Rothman;I. Howald;T. Stevens
中科院分区：
文献类型：
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作者：
J. Rothman;I. Howald;T. Stevens
为了进一步研究酵母中溶酶体样液泡的蛋白质分选和生物发生，我们分离出了 11 个新的 VPL 互补组的自发突变，以及先前描述的 8 个 VPL 基因的其他等位基因。这些突变体是通过选择将液泡蛋白错误定位到细胞表面的细胞来鉴定的。 vpl 突变体的形态学检查表明大多数含有正常外观的液泡；然而，一些突变体通常缺乏大液泡，而是积累较小的细胞器。在 19 个 VPL 互补组中，有 12 个被发现与另一项研究中确定的 33 个 VPT 互补组中的 12 个相同。此外，end1突变体和所有先前报道的pep突变体（除了pep4）都被发现表现出严重的液泡蛋白分选缺陷，并且PEP、VPL VPT和END1组之间的互补测试表明这些组之间存在广泛的重叠。总的来说，这四个集合中的突变体定义了传递或保留可溶性液泡酶所需的 49 个互补组，包括羧肽酶 Y (CPY) 和蛋白酶 A。我们还分离了 462 个缺乏正常水平的液泡 CPY 活性的新突变体。在这些后面的突变体中，只有 pep4 突变体被发现在液泡酶原激活方面存在特异性缺陷。我们的结论是，酵母中液泡蛋白的分选或保留需要大量的基因产物，并且只有一个基因 PEP4 对 CPY 和其他液泡酶原的激活至关重要。
To further our studies of protein sorting and biogenesis of the lysosome‐like vacuole in yeast, we have isolated spontaneous mutations in 11 new VPL complementation groups, as well as additional alleles of the eight previously described VPL genes. These mutants were identified by selecting for cells that mislocalize vacuolar proteins to the cell surface. Morphological examination of the vpl mutants indicated that most contain vacuoles of normal appearance; however, some of the mutants generally lack a large vacuole, and instead accumulate smaller organelles. Of the 19 VPL complementation groups, 12 were found to be identical to 12 of 33 VPT complementation groups identified in a separate study. Moreover, the end1 mutant and all of the previously reported pep mutants, with the exception of pep4, were found to exhibit a profound vacuolar protein sorting defect, and complementation tests between the PEP, VPL VPT and END1 groups demonstrated that there are extensive overlaps between these groups. Collectively, mutants in these four collections define 49 complementation groups required to deliver or retain soluble vacuolar enzymes, including carboxypeptidase Y (CPY) and proteinase A. We have also isolated 462 new mutants that lack normal levels of vacuolar CPY activity. Among these latter mutants, only pep4 mutants were found to be specifically defective in vacuolar zymogen activation. We conclude that there is a large number of gene products required for sorting or retention of vacuolar proteins in yeast, and only a single gene, PEP4, that is essential for activation of CPY and other vacuolar zymogens.