Drosophila MCM protein complexes.
Drosophila MCM protein complexes.
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果蝇 MCM 蛋白复合物。
DOI：
10.1091/mbc.7.2.319
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发表时间：
1996
影响因子：
3.3
通讯作者：
O'Farrell,PH
中科院分区：
文献类型：
--
作者：
Su,TT;Feger,G;O'Farrell,PH
MCM基因编码DNA复制所需的进化上保守的蛋白质家族。在首次发现MCM基因的酿酒酵母中，MCM基因在遗传上相互作用。这些相互作用中的等位基因特异性表明MCM蛋白质在物理上相互关联，并且这种关联对于功能是必不可少的。我们在这里描述了三个果蝇MCM蛋白之间的物理相互作用的分析。使用特异性抗体，我们检测果蝇MCMs几乎完全在600 kDa的蛋白质复合物。免疫共沉淀数据表明存在至少两种不同类型的600-kDa复合物，一种含有DmCDC 46，另一种似乎含有DmMCM 2和Dpa（CDC 54同源物）。这些复合物在整个胚胎分裂周期中是稳定的，对盐和去污剂的处理具有抗性，并且在发育期间存在于经历有丝分裂DNA复制以及内复制的组织中。当在低盐条件下制备提取物时，所有三种MCM蛋白质共免疫沉淀。因此，我们认为，600 kDa的复合物相互作用在一个更高的顺序复杂。
MCM genes encode a family of evolutionarily conserved proteins required for DNA replication. In Saccharomyces cerevisiae, where they were first identified, MCM genes interact genetically with each other. Allele specificity in these interactions suggests that MCM proteins physically associate with one another and that this association is essential for function. We describe here an analysis of physical interactions among three Drosophila MCM proteins. Using specific antibodies we detect Drosophila MCMs almost exclusively in 600-kDa protein complexes. Co-immunoprecipitation data demonstrate the existence of at least two distinct types of 600-kDa complexes, one that contains DmCDC46 and one that appears to contain both DmMCM2 and Dpa (a CDC54 homologue). These complexes are stable throughout embryonic division cycles, are resistant to treatments with salt and detergent, and are present during development in tissues undergoing mitotic DNA replication as well as endoreplication. When extracts are prepared under low salt conditions all three MCM proteins co-immunoprecipitate. Consequently, we suggest that the 600-kDa complexes interact in a higher order complex.