Role for Drs2p, a P-type ATPase and potential aminophospholipid translocase, in yeast late Golgi function.
Role for Drs2p, a P-type ATPase and potential aminophospholipid translocase, in yeast late Golgi function.
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Drs2p的作用，P型ATPase和潜在的氨基磷脂易位酶，在高尔基酵母晚期功能中。
DOI：
10.1083/jcb.147.6.1223
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发表时间：
1999-12-13
影响因子：
7.8
通讯作者：
Graham, T R
中科院分区：
文献类型：
--
作者：
Chen, C Y;Ingram, M F;Rosal, P H;Graham, T R
ADP-核糖基化因子似乎调节 COPI 和高尔基体膜上网格蛋白包被的转运囊泡的出芽。 arf1Δ 合成致死筛选鉴定出 SWA3/DRS2，它编码整合膜 P 型 ATP 酶和潜在的氨基磷脂转位酶（或翻转酶）。 drs2 无效等位基因对于网格蛋白重链 (chc1) 温度敏感等位基因也具有综合致死性，但对于 COPI 亚基或其他测试的 SEC 基因的突变则不然。与这些遗传分析一致，我们发现 drs2Δ 突变体表现出晚期高尔基体缺陷，这可能是由于该区室网格蛋白功能丧失所致。其中包括依赖于 Kex2 的前 α 因子加工过程中的缺陷以及异常高尔基体池的积累。此外，我们观察到从 drs2Δ 细胞中分离出的网格蛋白包被的囊泡显着减少。亚细胞分级分离和免疫荧光分析表明 Drs2p 定位于含有 Kex2p 的晚期高尔基体膜。这些观察结果表明 P 型 ATP 酶在晚期高尔基体功能中的新作用，并表明膜不对称性与高尔基复合体网格蛋白功能之间可能存在联系。
ADP-ribosylation factor appears to regulate the budding of both COPI and clathrin-coated transport vesicles from Golgi membranes. An arf1Δ synthetic lethal screen identified SWA3/DRS2, which encodes an integral membrane P-type ATPase and potential aminophospholipid translocase (or flippase). The drs2 null allele is also synthetically lethal with clathrin heavy chain (chc1) temperature-sensitive alleles, but not with mutations in COPI subunits or other SEC genes tested. Consistent with these genetic analyses, we found that the drs2Δ mutant exhibits late Golgi defects that may result from a loss of clathrin function at this compartment. These include a defect in the Kex2-dependent processing of pro–α-factor and the accumulation of abnormal Golgi cisternae. Moreover, we observed a marked reduction in clathrin-coated vesicles that can be isolated from the drs2Δ cells. Subcellular fractionation and immunofluorescence analysis indicate that Drs2p localizes to late Golgi membranes containing Kex2p. These observations indicate a novel role for a P-type ATPase in late Golgi function and suggest a possible link between membrane asymmetry and clathrin function at the Golgi complex.