Ogiwara Hideaki, Ui Ayako, Kawashima Satoshi, Kugou Kazuto, Onoda Fumitoshi, Iwahashi Hitoshi, Harata Masahiko, Ohta Kunihiro, Enomoto Takemi, Seki Masayuki
Molecular Cell Biology Laboratory, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai, Miyagi 980-8578, Japan.
Nucleic Acids Res. 2007;35(9):3109-17. doi: 10.1093/nar/gkm161. Epub 2007 Apr 22.
The actin-related proteins (Arps) comprise a conserved protein family. Arp4p is found in large multisubunits of the INO80 and SWR1 chromatin remodeling complexes and in the NuA4 histone acetyltransferase complex. Here we show that arp4 (arp4S23A/D159A) temperature-sensitive cells are defective in G2/M phase function. arp4 mutants are sensitive to the microtubule depolymerizing agent benomyl and arrest at G2/M phase at restrictive temperature. Arp4p is associated with centromeric and telomeric regions throughout cell cycle. Ino80p, Esa1p and Swr1p, components of the INO80, NuA4 and SWR1 complexes, respectively, also associate with centromeres. The association of many kinetochore components including Cse4p, a component of the centromere nucleosome, Mtw1p and Ctf3p is partially impaired in arp4 cells, suggesting that the G2/M arrest of arp4 mutant cells is due to a defect in formation of the chromosomal segregation apparatus.
肌动蛋白相关蛋白（Arps）构成一个保守的蛋白家族。Arp4p存在于INO80和SWR1染色质重塑复合物的大型多亚基中以及NuA4组蛋白乙酰转移酶复合物中。在此我们表明，arp4（arp4S23A/D159A）温度敏感型细胞在G2/M期功能方面存在缺陷。arp4突变体对微管解聚剂苯菌灵敏感，并在限制温度下停滞于G2/M期。Arp4p在整个细胞周期中都与着丝粒区域和端粒区域相关联。INO80、NuA4和SWR1复合物的组分Ino80p、Esa1p和Swr1p也分别与着丝粒相关联。包括着丝粒核小体的一个组分Cse4p、Mtw1p和Ctf3p在内的许多动粒组分的关联在arp4细胞中部分受损，这表明arp4突变体细胞的G2/M期停滞是由于染色体分离装置形成缺陷所致。
