Novel Golgi to vacuole delivery pathway in yeast: Identification of a sorting determinant and required transport component
Novel Golgi to vacuole delivery pathway in yeast: Identification of a sorting determinant and required transport component
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DOI：
10.1093/emboj/16.10.2769
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发表时间：
1997-05-15
期刊：
影响因子：
11.4
通讯作者：
Emr, SD
中科院分区：
文献类型：
--
作者：
Cowles, CR;Snyder, WB;Emr, SD
已经鉴定了40多种液泡蛋白分选（vps）突变体，它们将可溶性液泡水解酶的酶原形式分泌到细胞表面。这些突变体中的一个亚组被发现在两种液泡膜蛋白的分选中显示出选择性缺陷。（SEC 1同源物）和pep 12/vps 6（tsf）（内体t-SNARE）突变体有效地将碱性磷酸酶（ALP）分选到液泡中，而多种可溶性液泡蛋白和膜蛋白羧肽酶yscS（CPS）不再被递送到液泡中，在这些突变体中ALP的双极性定位不需要转运到质膜，然后被内吞摄取，因为pep 12（tsf）和vps 45（tsf）的双突变体具有sec 1和end 3排序和在非允许温度下的成熟ALP。考虑到t-SNARE如Pep 12 p在转运囊泡识别中的已证实的作用，我们的结果表明，ALP和CPS被包装成不同的转运中间体。与ALP沿着另一条途径进入液泡一致，vps 41（tsf）突变体的分离揭示了在非允许温度下，ALP被错误定位，而CPS和CPY的液泡递送得以维持。我们的数据表明，ALP胞质尾区的氨基端16个氨基酸部分包含一个液泡分选信号，它负责主动识别、包装和运输ALP从高尔基体通过一种新的递送途径进入液泡。
More than 40 vacuolar protein sorting (vps) mutants have been identified which secrete proenzyme forms of soluble vacuolar hydrolases to the cell surface. A subset of these mutants has been found to show selective defects in the sorting of two vacuolar membrane proteins, Under non-permissive conditions, vps45(tsf) (SEC1 homolog) and pep12/vps6(tsf) (endosomal t-SNARE) mutants efficiently sort alkaline phosphatase (ALP) to the vacuole while multiple soluble vacuolar proteins and the membrane protein carboxypeptidase yscS (CPS) are no longer delivered to the vacuole, Vacuolar localization of ALP in these mutants does not require transport to the plasma membrane followed by endocytic uptake, as double mutants of pep12(tsf) and vps45(tsf) with sec1 and end3 sort and mature ALP at the non-permissive temperature, Given the demonstrated role of t-SNAREs such as Pep12p in transport vesicle recognition, our results indicate that ALP and CPS are packaged into distinct transport intermediates, Consistent with ALP following an alternative route to the vacuole, isolation of a vps41(tsf) mutant revealed that at non-permissive temperature ALP is mislocalized while vacuolar delivery of CPS and CPY is maintained. A series of domain-swapping experiments was used to define the sorting signal that directs selective packaging and transport of ALP, Our data demonstrate that the amino-terminal 16 amino acid portion of the ALP cytoplasmic tail domain contains a vacuolar sorting signal which is responsible for the active recognition, packaging and transport of ALP from the Golgi to the vacuole via a novel delivery pathway.