Mer G, Bochkarev A, Gupta R, Bochkareva E, Frappier L, Ingles C J, Edwards A M, Chazin W J
Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
Cell. 2000 Oct 27;103(3):449-56. doi: 10.1016/s0092-8674(00)00136-7.
Replication protein A (RPA), the nuclear ssDNA-binding protein in eukaryotes, is essential to DNA replication, recombination, and repair. We have shown that a globular domain at the C terminus of subunit RPA32 contains a specific surface that interacts in a similar manner with the DNA repair enzyme UNG2 and repair factors XPA and RAD52, each of which functions in a different repair pathway. NMR structures of the RPA32 domain, free and in complex with the minimal interaction domain of UNG2, were determined, defining a common structural basis for linking RPA to the nucleotide excision, base excision, and recombinational pathways of repairing damaged DNA. Our findings support a hand-off model for the assembly and coordination of different components of the DNA repair machinery.
复制蛋白A(RPA)是真核生物中的核单链DNA结合蛋白,对DNA复制、重组和修复至关重要。我们已经表明,亚基RPA32 C末端的一个球状结构域包含一个特定表面,该表面以类似方式与DNA修复酶UNG2以及修复因子XPA和RAD52相互作用,它们各自在不同的修复途径中发挥作用。确定了RPA32结构域游离状态以及与UNG2最小相互作用结构域形成复合物状态下的核磁共振结构,为将RPA与修复受损DNA的核苷酸切除、碱基切除和重组途径联系起来定义了一个共同的结构基础。我们的研究结果支持了DNA修复机制不同组分组装和协调的交接模型。