Otterlei Marit, Bruheim Per, Ahn Byungchan, Bussen Wendy, Karmakar Parimal, Baynton Kathy, Bohr Vilhelm A
Laboratory of Molecular Gerontology, National Institute on Aging, NIH, 5600 Nathan Shock Dr., Baltimore, MD 21224, USA.
J Cell Sci. 2006 Dec 15;119(Pt 24):5137-46. doi: 10.1242/jcs.03291. Epub 2006 Nov 21.
Werner syndrome (WS) is a rare genetic disorder characterized by genomic instability caused by defects in the WRN gene encoding a member of the human RecQ helicase family. RecQ helicases are involved in several DNA metabolic pathways including homologous recombination (HR) processes during repair of stalled replication forks. Following introduction of interstrand DNA crosslinks (ICL), WRN relocated from nucleoli to arrested replication forks in the nucleoplasm where it interacted with the HR protein RAD52. In this study, we use fluorescence resonance energy transfer (FRET) and immune-precipitation experiments to demonstrate that WRN participates in a multiprotein complex including RAD51, RAD54, RAD54B and ATR in cells where replication has been arrested by ICL. We verify the WRN-RAD51 and WRN-RAD54B direct interaction in vitro. Our data support a role for WRN also in the recombination step of ICL repair.
沃纳综合征（WS）是一种罕见的遗传性疾病，其特征是由编码人类RecQ解旋酶家族成员的WRN基因缺陷导致基因组不稳定。RecQ解旋酶参与多种DNA代谢途径，包括在停滞复制叉修复过程中的同源重组（HR）过程。引入链间DNA交联（ICL）后，WRN从核仁重新定位到核质中停滞的复制叉处，在那里它与HR蛋白RAD52相互作用。在本研究中，我们使用荧光共振能量转移（FRET）和免疫沉淀实验来证明，在因ICL而导致复制停滞的细胞中，WRN参与了一个包括RAD51、RAD54、RAD54B和ATR的多蛋白复合物。我们在体外验证了WRN与RAD51和WRN与RAD54B的直接相互作用。我们的数据支持WRN在ICL修复的重组步骤中也发挥作用。
