THE END3 GENE ENCODES A PROTEIN THAT IS REQUIRED FOR THE INTERNALIZATION STEP OF ENDOCYTOSIS AND FOR ACTIN CYTOSKELETON ORGANIZATION IN YEAST
THE END3 GENE ENCODES A PROTEIN THAT IS REQUIRED FOR THE INTERNALIZATION STEP OF ENDOCYTOSIS AND FOR ACTIN CYTOSKELETON ORGANIZATION IN YEAST
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DOI：
10.1091/mbc.5.9.1023
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发表时间：
1994-09-01
影响因子：
3.3
通讯作者：
RIEZMAN, H
中科院分区：
文献类型：
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作者：
BENEDETTI, H;RATHS, S;RIEZMAN, H
两个酿酒酵母突变体，end 3和end 4，在内吞作用的内化步骤中有缺陷，先前已被分离。通过互补由end 3突变引起的温度敏感性生长缺陷来克隆END 3基因，并确定END 3核苷酸序列。END 3基因产物是一个40 kDa的蛋白质，具有推定的EF-手Ca 2+结合位点、用于结合磷脂酰肌醇4，5-二磷酸（PIP 2）的共有序列和含有两个17-19 aa同源区域的C-末端结构域。EF-手的共识和推定的PIP 2结合位点似乎不需要End 3蛋白的功能。相反，End 3 p N-末端结构域的不同部分，以及其C-末端的两个重复区域中的至少一个，是End 3 p活性所需的。END 3基因的破坏产生了与原始end 3突变体具有相同表型的细胞。获得了end 3（ts）等位基因，这使我们能够证明End 3 p特异性地参与内吞作用的内化步骤。此外，End 3 p被证明是所需的肌动蛋白细胞骨架的正确组织和正确的分布在细胞表面的几丁质。
Two Saccharomyces cerevisiae mutants, end3 and end4, defective in the internalization step of endocytosis, have previously been isolated. The END3 gene was cloned by complementation of the temperature-sensitive growth defect caused by the end3 mutation and the END3 nucleotide sequence was determined. The END3 gene product is a 40-kDa protein that has a putative EF-hand Ca2+-binding site, a consensus sequence for the binding of phosphotidylinositol 4,5-bisphosphate (PIP2), and a C-terminal domain containing two homologous regions of 17-19 aa. The EF-hand consensus and the putative PIP2-binding sites are seemingly not required for End3 protein function. In contrast, different portions of the End3p N-terminal domain, and at least one of the two repeated regions in its C-terminus, are required for End3p activity. Disruption of the END3 gene yielded cells with the same phenotype as the original end3 mutant. An end3(ts) allele was obtained and this allowed us to demonstrate that End3p is specifically involved in the internalization step of endocytosis. In addition, End3p was shown to be required for proper organization of the actin cytoskeleton and for the correct distribution of chitin at the cell surface.