Dissociation of Rb-binding and anchorage-independent growth from immortalization and tumorigenicity using SV40 mutants producing N-terminally truncated large T antigens.
Dissociation of Rb-binding and anchorage-independent growth from immortalization and tumorigenicity using SV40 mutants producing N-terminally truncated large T antigens.
复制标题
使用产生 N 末端截短的大 T 抗原的 SV40 突变体，将 Rb 结合和不依赖锚定的生长与永生化和致瘤性分离。
DOI：
10.1016/0042-6822(90)90375-2
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发表时间：
1990
期刊：
影响因子：
3.7
通讯作者：
Tevethia,MJ
中科院分区：
文献类型：
--
作者：
Thompson,DL;Kalderon,D;Smith,AE;Tevethia,MJ
SV40的大T抗原是小鼠原代细胞向表型完全转化的细胞转化的充分必要条件。本研究利用含有5‘T抗原编码序列缺失的突变体，探讨了T抗原N端部分对个体转化细胞特性的影响。具体地说，预期产生缺失前109、127、150或176个氨基酸或117至250个内部氨基酸片段的T抗原的DNA构建体被测试了使C57BI/6小鼠胚胎成纤维细胞永生化的能力。然后检查克隆获得的细胞系所显示的转化细胞特性。结果表明，T抗原的前127个氨基酸或127-250位氨基酸不是使原代细胞有效永生化或致瘤性所必需的。因此，在这些区域定位的功能，包括视网膜母细胞瘤易感基因产物(RB)的结合和异源启动子的反式激活，不需要赋予这两种生长特性中的任何一种。此外，研究结果表明，锚定非依赖性生长与致瘤性在遗传上是可以分离的，去除T抗原前250个残基中的氨基酸会影响转化细胞的其他生长特性。
The large T antigen of SV40 is both necessary and sufficient for conversion of primary mouse cells to cells with fully transformed phenotype. In this investigation, the influence of the N-terminal portion of T antigen on individual transformed cell characteristics was probed by using mutants bearing deletions in the 5′ T antigen coding sequence. Specifically, DNA constructs expected to produce T antigens missing the first 109, 127, 150, or 176 amino acids or internal amino acid segments between 117 and 250 were tested for the ability to immortalize C57BI/6 mouse embryo fibroblasts. The transformed cell properties displayed by clonally derived cell lines were then examined. The results indicated that neither the first 127 amino acids nor amino acids 127–250 of T antigen were necessary for efficient immortalization of primary cells or for their tumorigenicity. Functions mapped within these regions, including binding of the retinoblastoma susceptibility gene product (Rb) and transactivation of heterologous promoters, therefore, were not required to confer either of these growth properties. In addition the results showed that anchorage-independent growth was separable genetically from tumorigenicity and that removal of amino acids within the first 250 residues of T antigen compromised other transformed cell growth properties.