CRYSTALLOGRAPHIC STUDIES OF DNA REPLICATION & CELLULAR SIGNALING: ONCOGENE

STAT-1同源二聚体DNA复合体的晶体结构 已确定为2.9决议。STAT-1利用DNA结合 具有免疫球蛋白折叠的结构域，类似于NFkB和 P53抑癌蛋白。STAT-1二聚体形成连续的 围绕DNA的C形夹子，由相互作用和高度稳定 一种单体的SH2结构域与 另一个是酪氨酸磷酸化的C-末端片段。这个 各单体中SH2结构域的磷酸酪氨酸结合部位为 在结构上连接到DNA结合域，暗示了一种潜在的 SH2-磷酸酪氨酸相互作用在稳定化中的作用 DNA相互作用的元素。

The crystal structure of the DNA complex of a STAT-1 homodimer has been determined at 2.9
resolution. STAT-1 utilizes a DNA binding domain with an immunoglobulin fold, similar to that of NFkB and the p53 tumor suppressor protein. The STAT-1 dimer forms a contiguous C-shaped clamp around DNA that is stabilized by reciprocal and highly specific interactions between the SH2 domain of one monomer and the C-terminal segment, phosphorylated on tyrosine, of the other. The phosphotyrosine binding site of the SH2 domain in each monomer is coupled structurally to the DNA binding domain, suggesting a potential role for the SH2-phosphotyrosine interaction in the stabilization of DNA interacting elements.