生物谷：瑞典卡羅林斯卡醫(yī)學院日前說,，他們研究發(fā)現(xiàn)了受損ＤＮＡ（脫氧核糖核酸）的修復機理,，這將有助于癌癥研究,。
卡羅林斯卡醫(yī)學院的卡米拉·肖格倫在１４日向記者提供的資料中說,，細胞分裂前,，一個ＤＮＡ分子將會被復制成兩個,，并通過一種叫做Ｃｏｈｅｓｉｎ的物質黏合在一起,。一旦兩個ＤＮＡ分子分開太早，新生成的細胞中的染色體（ＤＮＡ分子的主要載體）數(shù)量就可能出現(xiàn)異常,，正像很多腫瘤細胞的染色體數(shù)量異常一樣,。
瑞典研究人員發(fā)現(xiàn)，與通常的認識不同,，細胞會使用Ｃｏｈｅｓｉｎ來修復受損的ＤＮＡ鏈,。肖格倫說，這項發(fā)現(xiàn)涉及到細胞最基本的工作機理,，對癌癥研究無疑具有重要意義,。
這項研究刊登在１３日出版的美國《科學》雜志上。（新華網）
原始出處:
Science 13 July 2007:
Vol. 317. no. 5835, pp. 242 - 245
DOI: 10.1126/science.1140649
Postreplicative Formation of Cohesion Is Required for Repair and Induced by a Single DNA Break
Lena Ström,1 Charlotte Karlsson,1 Hanna Betts Lindroos,1 Sara Wedahl,1 Yuki Katou,2 Katsuhiko Shirahige,2 Camilla Sjögren1*
Sister-chromatid cohesion, established during replication by the protein complex cohesin, is essential for both chromosome segregation and double-strand break (DSB) repair. Normally, cohesion formation is strictly limited to the S phase of the cell cycle, but DSBs can trigger cohesion also after DNA replication has been completed. The function of this damage-induced cohesion remains unknown. In this investigation, we show that damage-induced cohesion is essential for repair in postreplicative cells in yeast. Furthermore, it is established genome-wide after induction of a single DSB, and it is controlled by the DNA damage response and cohesin-regulating factors. We thus define a cohesion establishment pathway that is independent of DNA duplication and acts together with cohesion formed during replication in sister chromatid–based DSB repair.
1 Department of Cell and Molecular Biology, Karolinska Institute, 171 77 Stockholm, Sweden.
2 Gene Research Centre, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, 226-8501 Yokohama, Japan.
* To whom correspondence should be addressed. E-mail: [email protected]
