A B-Myb complex containing clathrin and filamin is required for mitotic spindle function
A B-Myb complex containing clathrin and filamin is required for mitotic spindle function
复制标题
DOI：
10.1038/emboj.2008.118
复制
发表时间：
2008-07-09
期刊：
影响因子：
11.4
通讯作者：
Ishii, Shunsuke
中科院分区：
文献类型：
--
作者：
Yamauchi, Tomohiro;Ishidao, Takefumi;Ishii, Shunsuke
B-Myb是脊椎动物Myb转录因子家族的成员之一，广泛表达。B-Myb通过形成dREAM/Myb MuvB样复合物激活G2/M细胞周期转换所需的一组基因的转录，该复合物最初在果蝇中鉴定。斑马鱼B-myb和果蝇myb的突变体表现出细胞周期进程和基因组不稳定性的缺陷。虽然B-Myb缺失引起的基因组不稳定性被推测是由于细胞周期进程异常，但确切的机制仍然未知。在这里，我们已经纯化了含有网格蛋白和细丝蛋白的B-Myb复合物（Myb-Clafi复合物）。该复合物是有丝分裂纺锤体网格蛋白正常定位所需的，以前曾报道其可稳定动粒纤维。Myb-Clafi复合物与有丝分裂纺锤体不紧密相关，这表明该复合物将网格蛋白运送到有丝分裂纺锤体。因此，Myb-Clafi复合物的鉴定揭示了B-Myb先前未被识别的功能，该功能可能有助于其在染色体稳定性中的作用，可能是肿瘤抑制。
B-Myb is one member of the vertebrate Myb family of transcription factors and is ubiquitously expressed. B-Myb activates transcription of a group of genes required for the G2/M cell cycle transition by forming the dREAM/Myb MuvB-like complex, which was originally identified in Drosophila. Mutants of zebrafish B-myb and Drosophila myb exhibit defects in cell cycle progression and genome instability. Although the genome instability caused by a loss of B-Myb has been speculated to be due to abnormal cell cycle progression, the precise mechanism remains unknown. Here, we have purified a B-Myb complex containing clathrin and filamin (Myb-Clafi complex). This complex is required for normal localization of clathrin at the mitotic spindle, which was previously reported to stabilize kinetochore fibres. The Myb-Clafi complex is not tightly associated with the mitotic spindles, suggesting that this complex ferries clathrin to the mitotic spindles. Thus, identification of the Myb-Clafi complex reveals a previously unrecognized function of B-Myb that may contribute to its role in chromosome stability, possibly, tumour suppression.