Imp2, the PSTPIP homolog in fission yeast, affects sensitivity to the immunosuppressant FK506 and membrane trafficking in fission yeast.
Imp2, the PSTPIP homolog in fission yeast, affects sensitivity to the immunosuppressant FK506 and membrane trafficking in fission yeast.
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Imp2 是裂殖酵母中的 PSTPIP 同源物，影响裂殖酵母中对免疫抑制剂 FK506 的敏感性和膜运输。
DOI：
10.1016/j.bbrc.2014.12.100
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Reiko Sugiura
中科院分区：
文献类型：
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作者：
Ayako Kita;Mari Higa;Akira Doi;Ryosuke Satoh;Reiko Sugiura
胞质分裂是将一个细胞分裂成两个细胞的高度有序的过程，其在功能上与质膜的动态重塑以及各种事件如膜运输协调相关。钙调神经磷酸酶是一种高度保守的丝氨酸/苏氨酸蛋白磷酸酶，调节多种生物学功能，如膜运输和胞质分裂。在这里，我们分离出dimp 2-c3，一个突变等位基因的imp 2+基因，编码同源的小鼠PSTPIP 1（脯氨酸-丝氨酸-苏氨酸磷酸酶相互作用蛋白1），使用基因筛选突变，是合成致死与钙调磷酸酶缺失裂殖酵母。imp 2-c3突变体表现出多分隔表型的胞质分裂缺陷，在用钙调磷酸酶抑制剂FK 506处理后进一步增强。电子显微镜观察发现，突变体细胞内聚集了异常的多片层高尔基体结构和高尔基体后分泌囊泡，细胞内空泡破碎，细胞间隔增厚。因此，突变体imp 2-c3表现出酸性磷酸酶分泌减少和液泡融合缺陷。imp 2-c3突变细胞表现出细胞壁弱化，与在相同遗传筛选中鉴定的膜运输突变体（例如ypt 3-i5）相似。这些发现暗示PSTPIP 1同源物Imp 2在高尔基体/液泡功能，从而影响各种细胞过程，包括胞质分裂和细胞完整性。
Cytokinesis is a highly ordered process that divides one cell into two cells, which is functionally linked to the dynamic remodeling of the plasma membrane coordinately with various events such as membrane trafficking. Calcineurin is a highly conserved serine/threonine protein phosphatase, which regulates multiple biological functions, such as membrane trafficking and cytokinesis. Here, we isolatedimp2-c3, a mutant allele of theimp2+gene, encoding a homolog of the mouse PSTPIP1 (proline-serine-threoninephosphataseinteractingprotein1), using a genetic screen for mutations that are synthetically lethal with calcineurin deletion in fission yeast. Theimp2-c3mutants showed a defect in cytokinesis with multi-septated phenotypes, which was further enhanced upon treatment with the calcineurin inhibitor FK506. Notably, electron micrographs revealed that theimp2-c3mutant cells accumulated aberrant multi-lamella Golgi structures and putative post-Golgi secretory vesicles, and exhibited fragmented vacuoles in addition to thickened septa. Consistently,imp2-c3mutants showed a reduced secretion of acid phosphatase and defects in vacuole fusion. Theimp2-c3mutant cells exhibited a weakened cell wall, similar to the membrane trafficking mutants identified in the same genetic screen such asypt3-i5. These findings implicate the PSTPIP1 homolog Imp2 in Golgi/vacuole function, thereby affecting various cellular processes, including cytokinesis and cell integrity.