A screen for dynein synthetic lethals in Aspergillus nidulans identifies spindle assembly checkpoint genes and other genes involved in mitosis.
A screen for dynein synthetic lethals in Aspergillus nidulans identifies spindle assembly checkpoint genes and other genes involved in mitosis.
复制标题
对构巢曲霉中动力蛋白合成致死细胞的筛选鉴定了纺锤体组装检查点基因和其他参与有丝分裂的基因。
DOI：
10.1093/genetics/149.1.101
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发表时间：
1998
期刊：
影响因子：
3.3
通讯作者：
Morris,NR
中科院分区：
文献类型：
--
作者：
Efimov,VP;Morris,NR
细胞质动力蛋白是一种普遍表达的微管马达，参与囊泡运输、有丝分裂、核迁移和纺锤体定位。在丝状真菌nidulans中，细胞质动力蛋白的失活虽然不致命，但会严重损害核迁移。动力蛋白在该生物有丝分裂和囊泡运输中的作用尚不清楚。为了研究弧菌动力蛋白功能的完整范围，我们寻找在没有动力蛋白的情况下显著抑制生长的合成致命突变，但它们本身几乎没有影响。我们在9个不同的基因中分离出19个SLD(不含动力蛋白的合成致死性)突变。两个基因的突变加剧了在缺乏动力蛋白的情况下出现的核迁移缺陷。包括sldA和sldB在内的其他六个基因的突变与BIMC中有丝分裂运动的突变显示出强烈的合成致命性相互作用，因此，很可能在有丝分裂中发挥作用。SldA和sldB的突变也使微管破坏稳定的药物苯菌灵产生过敏反应。利用根瘤拟青霉自主复制载体，通过突变表型互补，克隆了sLdA和sLdB。测序结果显示与酿酒酵母的纺锤体组装检查点基因bub1和bub3具有同源性。动力蛋白和纺锤体组装检查点基因以及其他有丝分裂基因之间的遗传交互作用表明，动力蛋白在有丝分裂中发挥了作用。我们提出了一个模型，可以解释动力蛋白在有丝分裂和核分布中的作用。
Cytoplasmic dynein is a ubiquitously expressed microtubule motor involved in vesicle transport, mitosis, nuclear migration, and spindle orientation. In the filamentous fungus Aspergillus nidulans, inactivation of cytoplasmic dynein, although not lethal, severely impairs nuclear migration. The role of dynein in mitosis and vesicle transport in this organism is unclear. To investigate the complete range of dynein function in A. nidulans, we searched for synthetic lethal mutations that significantly reduced growth in the absence of dynein but had little effect on their own. We isolated 19 sld (syntheticlethality withoutdynein) mutations in nine different genes. Mutations in two genes exacerbate the nuclear migration defect seen in the absence of dynein. Mutations in six other genes, including sldA and sldB, show a strong synthetic lethal interaction with a mutation in the mitotic kinesin bimC and, thus, are likely to play a role in mitosis. Mutations in sldA and sldB also confer hypersensitivity to the microtubule-destabilizing drug benomyl. sldA and sldB were cloned by complementation of their mutant phenotypes using an A. nidulans autonomously replicating vector. Sequencing revealed homology to the spindle assembly checkpoint genes BUB1 and BUB3 from Saccharomyces cerevisiae. Genetic interaction between dynein and spindle assembly checkpoint genes, as well as other mitotic genes, indicates that A. nidulans dynein plays a role in mitosis. We suggest a model for dynein motor action in A. nidulans that can explain dynein involvement in both mitosis and nuclear distribution.