Simian virus 40 small-t protein is required for loss of actin cable networks in rat cells
Simian virus 40 small-t protein is required for loss of actin cable networks in rat cells
复制标题
猿猴病毒 40 小-t 蛋白是大鼠细胞肌动蛋白电缆网络丢失所必需的
作者：
A. Graessmann;M. Graessmann;R. Tjian;W. Topp
在大鼠胚胎成纤维细胞中，显微注射完整的SV 40 DNA、来自SV 40早期区的DNA片段、以及从用腺病毒-SV 40杂合病毒Ad 2 +D2感染的细胞中分离的纯化的SV 40大T抗原相关蛋白（D2杂合蛋白）。注射107，000-道尔顿D2杂合蛋白或缺失突变体d1 884 SV 40的SV 40 DNA（缺失编码小t抗原的部分区域（0.54 - 0.59）），在72小时内，受体细胞中肌动蛋白索结构没有任何可检测的变化。相比之下，注射野生型SV 40 DNA或含有编码小t抗原的整个区域的DNA片段导致在注射后24小时内肌动蛋白电缆网络的破坏。看来很可能是SV 40小t蛋白是必要的流产损失肌动蛋白电缆在注射的细胞。表皮生长因子也会导致大鼠胚胎成纤维细胞或大鼠1细胞（一种已建立的大鼠胚胎细胞系）中肌动蛋白索的损失，但仅在细胞暴露于培养基中的表皮生长因子后，而不是在将表皮生长因子注射到细胞中后。
The ability of the two early simian virus 40 (SV40) coded proteins, the large and small T-antigens, to abortively induce the disappearance of cytoplasmic actin-containing networks in cultured cells has been studied in rat embryo fibroblasts after microinjection of intact SV40 DNA, DNA fragments from the early region of SV40, and a purified SV40 large T-antigen related protein (the D2 hybrid protein) isolated from cells infected with the adenovirus-SV40 hybrid virus Ad2+D2. Injection of either the 107,000-dalton D2 hybrid protein or SV40 DNA from the deletion mutant dl 884 SV40, which lacks part of the region (0.54 to 0.59) encoding small t-antigen, failed to cause any detectable change in the structure of actin cables in recipient cells over a period of 72 h. By contrast, injection of wild-type SV40 DNA or a DNA fragment containing the entire region coding for a small-t antigen leads to the disruption of actin cable networks within 24 h of injection. It appears likely that the SV40 small-t protein is necessary for the abortive loss of actin cables in injected cells. Epidermal growth factor also causes loss of actin cables in rat embryo fibroblasts or Rat 1 cells (an established rat embryo line), but only after exposure of the cells to epidermal growth factor in the culture medium and not after injection of epidermal growth factor into the cells.