Luv1p/Rki1p/Tcs3p/Vps54p, a yeast protein that localizes to the late Golgi and early endosome, is required for normal vacuolar morphology.
Luv1p/Rki1p/Tcs3p/Vps54p, a yeast protein that localizes to the late Golgi and early endosome, is required for normal vacuolar morphology.
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DOI：
10.1091/mbc.11.7.2429
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发表时间：
2000-07-01
影响因子：
3.3
通讯作者：
Cyert, MS
中科院分区：
文献类型：
--
作者：
Conboy, MJ;Cyert, MS
我们的特点LUV 1/RKI 1/TCS 3/VPS 54，一个新的酵母基因需要保持正常的空泡形态。luv 1突变体是在需要磷酸酶钙调神经磷酸酶营养生长的突变体的遗传筛选中鉴定的。luv 1突变体缺乏形态完整的液泡，而是积累酸化的小泡，含有液泡蛋白碱性磷酸酶和羧肽酶Y以及液泡膜H+-ATP酶。在luv 1突变体中，内吞作用在性质上是正常的，但部分（28%）的羧肽酶Y被分泌。luv 1突变体对几种离子（Zn 2+、Mn 2+和Cd 2+）和极端pH值敏感。这些突变体也对潮霉素B、咖啡因和FK 506（一种钙调磷酸酶的特异性抑制剂）敏感。一些液泡蛋白分选突变体显示出类似的药物和离子敏感性，包括对FK 506的敏感性。Luv 1 p在100，000 x g时沉淀，可被盐或碳酸盐溶解，表明它是一种外周膜蛋白。绿色荧光蛋白-Luv 1融合蛋白与染料FM 4-64共定位于内体，而血凝素标记的Luv 1 p与trans-Golgi网络/内体蛋白酶Kex 2 p共定位。计算机分析预测Luv 1 p中存在短卷曲螺旋结构域。我们建议，这种蛋白质保持交通通过或早期内体的完整性，这种功能是必要的适当的液泡形态。
We have characterized LUV1/RKI1/TCS3/VPS54, a novel yeast gene required to maintain normal vacuolar morphology. The luv1 mutant was identified in a genetic screen for mutants requiring the phosphatase calcineurin for vegetative growth. luv1 mutants lack a morphologically intact vacuole and instead accumulate small vesicles that are acidified and contain the vacuolar proteins alkaline phosphatase and carboxypeptidase Y and the vacuolar membrane H+-ATPase. Endocytosis appears qualitatively normal in luv1 mutants, but some portion (28%) of carboxypeptidase Y is secreted. luv1 mutants are sensitive to several ions (Zn2+, Mn2+, and Cd2+) and to pH extremes. These mutants are also sensitive to hygromycin B, caffeine, and FK506, a specific inhibitor of calcineurin. Some vacuolar protein-sorting mutants display similar drug and ion sensitivities, including sensitivity to FK506. Luv1p sediments at 100,000 x g and can be solubilized by salt or carbonate, indicating that it is a peripheral membrane protein. A Green Fluorescent Protein-Luv1 fusion protein colocalizes with the dye FM 4-64 at the endosome, and hemagglutinin-tagged Luv1p colocalizes with the trans-Golgi network/endosomal protease Kex2p. Computer analysis predicts a short coiled-coil domain in Luv1p. We propose that this protein maintains traffic through or the integrity of the early endosome and that this function is required for proper vacuolar morphology.