Merkle Carolin J, Karnitz Larry M, Henry-Sánchez John T, Chen Junjie
Graduate Program in Tumor Biology, Mayo Graduate School, Rochester, Minnesota 55905, USA.
J Biol Chem. 2003 Aug 8;278(32):30051-6. doi: 10.1074/jbc.M211591200. Epub 2003 May 23.
A growing body of evidence suggests that establishment of sister chromatid cohesion is dependent on replication fork passage over a precohesion area. In Saccharomyces cerevisiae, this process involves an alternative replication factor C (RFC) complex that contains the four small RFC subunits as well as CTF18, CTF8, and DCC1. Here, we show that an evolutionarily conserved homologous complex exists in the nucleus of human cells. We demonstrate that hCTF18, hCTF8, and hDCC1 interact with each other as well as with the p38 subunit of RFC. This alternative RFC-containing complex interacts with proliferating cell nuclear antigen but not with the Rad9/Rad1/Hus1 complex, a proliferating cell nuclear antigen-like clamp involved in the DNA damage response. hCTF18 preferentially binds chromatin during S phase, suggesting a role during replication. Our data provide evidence for the existence of an alternative RFC complex with a probable role in mammalian sister chromatid cohesion establishment.
越来越多的证据表明，姐妹染色单体黏连的建立依赖于复制叉通过一个前黏连区域。在酿酒酵母中，这一过程涉及一种替代复制因子C（RFC）复合物，该复合物包含四个小的RFC亚基以及CTF18、CTF8和DCC1。在这里，我们表明在人类细胞核中存在一种进化上保守的同源复合物。我们证明hCTF18、hCTF8和hDCC1彼此相互作用，并且与RFC的p38亚基相互作用。这种含替代RFC的复合物与增殖细胞核抗原相互作用，但不与Rad9/Rad1/Hus1复合物相互作用，Rad9/Rad1/Hus1复合物是一种参与DNA损伤反应的增殖细胞核抗原样夹子。hCTF18在S期优先结合染色质，表明其在复制过程中发挥作用。我们的数据为存在一种可能在哺乳动物姐妹染色单体黏连建立中起作用的替代RFC复合物提供了证据。
