Subclasses of simian virus 40 large T antigen: differential binding of two subclasses of T antigen from productively infected cells to viral and cellular DNA.
Subclasses of simian virus 40 large T antigen: differential binding of two subclasses of T antigen from productively infected cells to viral and cellular DNA.
复制标题
猿猴病毒 40 大 T 抗原的亚类：来自有效感染细胞的两个 T 抗原亚类与病毒和细胞 DNA 的差异结合。
作者：
'. E.Fanning;K.;D. Brauer;D. Corlin
Two major subclasses of simian virus 40 (SV40) large T antigen were separated by zone velocity sedimentation of crude extracts from productively infected cells. These subclasses, which have been shown to differ biologically and biochemically (Fanning et al., 1981), sedimented at 5‐6S and 14‐16S. The amount of T antigen in each form was estimated by complement fixation and by immunoprecipitation of T antigen from extracts of cells chronically labeled with [35S]methionine. Each form of T antigen was tested for specific binding to end‐labeled restriction fragments of SV40 DNA using an immunoprecipitation assay. The 5‐6S and 14‐16S forms of T antigen both bound specifically to DNA sequences in the SV40 HindIII C fragment. The sequences required for binding both forms were localized in the same 35‐bp region of the origin. However, significant differences in binding activity and affinity for specific and nonspecific DNA were demonstrated. These properties suggest that T antigen subclasses may serve different functions in the lytically infected cell.
