Mizuta R, Cheng H L, Gao Y, Alt F W
Howard Hughes Medical Institute, Children's Hospital, Boston, MA 02115, USA.
Int Immunol. 1997 Oct;9(10):1607-13. doi: 10.1093/intimm/9.10.1607.
XRCC4 is a generally expressed protein of 334 amino acids that is involved in the repair of DNA double-strand breaks and in V(D)J recombination, but its function is unknown. In this study, we have used a mutational approach and the yeast two-hybrid method to perform an initial characterization of this protein. We show that the XRCC4 protein is located in the nucleus. We also demonstrate that several potential phosphorylation sites are not required for XRCC4 function in a transient V(D)J recombination assay. In addition, we show that XRCC4 forms a homodimer in vivo with the homodimerization domain being located within amino acids 115-204. Finally, we define a core domain of XRCC4 that functions in V(D)J recombination and comprises amino acids 18-204. Potential functions of XRCC4 are discussed.
XRCC4是一种普遍表达的蛋白质，由334个氨基酸组成，参与DNA双链断裂修复和V(D)J重组，但其功能尚不清楚。在本研究中，我们采用突变方法和酵母双杂交方法对该蛋白质进行了初步表征。我们发现XRCC4蛋白定位于细胞核。我们还证明，在瞬时V(D)J重组试验中，几个潜在的磷酸化位点对于XRCC4的功能并非必需。此外，我们表明XRCC4在体内形成同二聚体，同二聚化结构域位于氨基酸115 - 204内。最后，我们确定了XRCC4在V(D)J重组中发挥作用的核心结构域，该结构域由氨基酸18 - 204组成。文中还讨论了XRCC4的潜在功能。
