Corsaro C M, Migeon B R
Proc Natl Acad Sci U S A. 1977 Oct;74(10):4476-80. doi: 10.1073/pnas.74.10.4476.
With an assay that quantitates the transfer of 6-thioguanylic acid from hypoxanthine phosphoribosyltransferase (IMP:pyrophosphate phosphoribosyltransferase, EC 2.4.2.8)-positive donor cells to negative recipient cells through gap junctions, differences in contact-mediated communication between normal and transformed human cells in culture have been detected. We have compared cells cultured from human tumors and simian virus 40-transformed cells with the normal human fibroblasts from which they were derived as well as with gap junction-deficient L cells. The communication, which is extensive in normal cells, is significantly reduced when transformed cells are used as either donors or recipients in the contact-feeding assay. Furthermore, the reduction in the transfer of nucleotides is enhanced when transformed cells are used as both donors and recipients, indicating a dosage effect or synergism, independent of enzyme activity. Fetal cells have a contact-feeding phenotype intermediate between that of normal and that of transformed cells. We suggest that the decrease in communication of nucleotides in transformed cells reflects quantitative or qualitative changes in membrane components responsible for gap junction formation.
通过一种定量分析方法，即检测次黄嘌呤磷酸核糖基转移酶（IMP：焦磷酸磷酸核糖基转移酶，EC 2.4.2.8）阳性供体细胞中的6-硫鸟苷酸通过间隙连接向阴性受体细胞的转移情况，已检测到培养的正常人类细胞与转化人类细胞之间接触介导通讯的差异。我们将从人类肿瘤培养的细胞、猿猴病毒40转化的细胞，与其来源的正常人类成纤维细胞以及缺乏间隙连接的L细胞进行了比较。在接触喂养分析中，当将转化细胞用作供体或受体时，正常细胞中广泛存在的通讯会显著减少。此外，当将转化细胞同时用作供体和受体时，核苷酸转移的减少会增强，这表明存在剂量效应或协同作用，且与酶活性无关。胎儿细胞的接触喂养表型介于正常细胞和转化细胞之间。我们认为，转化细胞中核苷酸通讯的减少反映了负责间隙连接形成的膜成分的数量或质量变化。
