CRYSTALLOGRAPHIC STUDIES OF KU70 & 80

我们得到了Ku70/80的小晶体，Ku70和Ku70的络合物 Ku80，与DNA结合，与ATP结合。两种蛋白Ku70和K80 共同构成DNA依赖的蛋白激酶的调节成分 (DNA-PK)，一种460kD的蛋白质，对DNA损伤做出反应。Ku70/80 复杂的结合与双链断裂和 双链到单链的转变。一旦绑定， Ku70/80复合体招募DNA-PK的催化亚基。突变 在Ku70/80或在催化亚单位中导致缺陷 修复双链DNA断裂。我们计划带着我们的水晶 至光束线7-1，以评估其质量。这其中的主要原因 必须在同步加速器上进行的实验是，晶体 非常小--最大的是0.1x0.1x0.1毫米。水晶 看起来像立方体。这些晶体的衍射几乎检测不到 在我们家的源头。我们预计单元格将具有 尺寸在300-400E数量级上。

We have obtained small crystals of Ku70/80, a complex of Ku70 and Ku80, bound to DNA and bound to ATP. The two proteins Ku70 and K80 together form the regulatory component of DNA-dependent protein kinase (DNA-PK), a 460 kD protein that responds to DNA damage. The Ku70/80 complex binds to double-stranded breaks and to double-stranded-to-single-stranded transitions. Once bound, the Ku70/80 complex recruits the catalytic subunit of DNA-PK. Mutations in either Ku70/80 or in the catalytic subunit result in defects in repair of double-stranded DNA breaks. We plan to bring our crystals to beamline 7-1 to assess their quality. The principal reason this experiment has to be done at a synchrotron is that the crystals are extremely small -- the largest are 0.1 x 0.1 x 0.1 mm. The crystals appear cubic. Diffraction from these crystals can barely be detected at our home source. We anticipate that the unit cell will have dimensions on the order of 300-400 E.