Department of Life Sciences, Kagawa University, Miki-cho, Kagawa 761-0795, Japan.
J Biosci Bioeng. 2011 Oct;112(4):309-14. doi: 10.1016/j.jbiosc.2011.06.009. Epub 2011 Jul 14.
In eukaryotic cells, SNARE proteins are essential for intracellular vesicle trafficking. Several SNARE proteins are required for vacuolar protein transport and vacuolar biogenesis in Saccharomyces cerevisiae. Previously we demonstrated that one of the fission yeast SNARE proteins, Pep12p, is not required for vacuolar fusion process in Schizosaccharomyces pombe. We have re-examined the function of S. pombe Pep12p using the newly created pep12(+) deletion strain. Deletion of the fission yeast pep12(+) gene results in pleiotropic phenotypes consistent with the absence of normal vacuoles, including missorting of vacuolar carboxypeptidase Y-and various ion- and drug-sensitivities. GFP-Pep12 fusion protein is mostly localized at the vacuolar membrane and the prevacuolar compartment. The S. pombe pep12Δ mutation phenocopies that of vps33Δ, suggesting that both Pep12p and Vps33p act at the same membrane fusion step in S. pombe, and both mutations cause vacuolar deficiency.
在真核细胞中，SNARE 蛋白对于细胞内囊泡运输是必不可少的。在酿酒酵母中，几种 SNARE 蛋白对于液泡蛋白运输和液泡发生是必需的。之前我们证明了裂殖酵母 SNARE 蛋白之一 Pep12p 对于 Schizosaccharomyces pombe 中的液泡融合过程不是必需的。我们使用新创建的 pep12(+)缺失菌株重新研究了 S. pombe Pep12p 的功能。裂殖酵母 pep12(+)基因的缺失导致多效表型，与正常液泡缺失一致，包括液泡羧肽酶 Y 和各种离子和药物敏感性的错误分拣。GFP-Pep12 融合蛋白主要定位于液泡膜和前液泡区室。S. pombe pep12Δ 突变与 vps33Δ 的表型相同，表明 Pep12p 和 Vps33p 都在 S. pombe 中的相同膜融合步骤中起作用，并且两种突变都导致液泡缺乏。
