DeCaprio J A
Dana-Farber Cancer Institute, Harvard Medical School, 44 Binney Street, Boston, Massachusetts 02115, USA.
Biologicals. 1999 Mar;27(1):23-8. doi: 10.1006/biol.1998.0173.
SV40 large T antigen (TAg)-mediated transformation is dependent on binding to p53 and the retinoblastoma tumor suppressor protein (pRB) and inactivating their growth suppressive functions. Transformation minimally requires three regions of TAg: a C-terminal domain that mediates binding to p53; the LXCXE motif (residues 103-107), necessary for binding to pRB and the related proteins p107 and p130; and an N-terminal domain (residues 1-82) that contains homology to the J domain found in cellular DnaJ/Hsp40 molecular chaperone proteins. We have found that the N-terminal J domain of T Ag cooperates with the LXCXE motif to inactivate the growth suppressive functions of the pRB-related proteins.
SV40大T抗原(TAg)介导的转化依赖于与p53和视网膜母细胞瘤肿瘤抑制蛋白(pRB)结合并使其生长抑制功能失活。转化至少需要TAg的三个区域:介导与p53结合的C末端结构域;与pRB以及相关蛋白p107和p130结合所必需的LXCXE基序(第103 - 107位氨基酸残基);以及与细胞DnaJ/Hsp40分子伴侣蛋白中发现的J结构域具有同源性的N末端结构域(第1 - 82位氨基酸残基)。我们发现TAg的N末端J结构域与LXCXE基序协同作用,使pRB相关蛋白的生长抑制功能失活。