A synthetic polypeptide, pt27, which is encoded by a cDNA clone with antloncogene activity, p14-6, is found to be able to reduce remarkably the soft agar colony formation ability of part of DT cells and to raise their...A synthetic polypeptide, pt27, which is encoded by a cDNA clone with antloncogene activity, p14-6, is found to be able to reduce remarkably the soft agar colony formation ability of part of DT cells and to raise their resistance to the ouabaln toxtcity. This shows that the pt27 peptide can affect the DT cells In a manner similar to the p14- 6 done and provides evidence that the reverting action of the p14-6 to DT cells may be exerted by the expression of its cDNA.展开更多
A cDNA clone, p14--6, which has an antioncogene activity on the v--Ki--Ras oncogene-transformed malignant cell line DT, was found. This clone was recovered from the revertantR14 cells, which had been isolated by trans...A cDNA clone, p14--6, which has an antioncogene activity on the v--Ki--Ras oncogene-transformed malignant cell line DT, was found. This clone was recovered from the revertantR14 cells, which had been isolated by transfections of DT cells with a normal human fibro-blast cDNA library cloned in pcD2, an Okayama-Berg vector. When transfected into DT cells,p14--6 clone gave rise to phenotypical flat reversion in 5--15% of DT transfectant colo-nies. The p14--6--transfected flat cell line, RR, was proven to be a true revertant with signif-icantly reduced malignancy by in ritro and in riro malignancy tests. All other clones recov-ered from R14 cells were unable to cause this reversion. Molecular hybridizations showedthat the p14--6 was inserted into RR genome as tandem repeats, and no structural changewas found in the D--Ki--Ras oncogene in RR genome. These facts suggest that the antioncogeneactivity of the p14--6 clone on the DT cells may be exerted through expression of thecDNA contained in this clone. Possible reasons for the non-reversion of part of DT cells after p14--6 transfection isdiscussed.展开更多
用 Northem Blot 方法研究了固真方对老年大鼠肝组织与增殖有关的基因——原癌基因(C-Ha-ras、c-myc)和抗癌基因(P53)表达的影响。结果显示:(1)c-Ha-rds、c-myc 的表达:老年对照组较青年对照组分别降低了61.8％和58.3％;老年用药组较老...用 Northem Blot 方法研究了固真方对老年大鼠肝组织与增殖有关的基因——原癌基因(C-Ha-ras、c-myc)和抗癌基因(P53)表达的影响。结果显示:(1)c-Ha-rds、c-myc 的表达:老年对照组较青年对照组分别降低了61.8％和58.3％;老年用药组较老年对照组分别增高了1.25和0.56倍。(2)P53的表达:老年对照组较青年对照组升高了0.89倍,而老年用药组较老年对照组降低了0.83倍。结果有助于揭示中药固真方补肾益精、延缓衰老作用的分子机理。展开更多
文摘A synthetic polypeptide, pt27, which is encoded by a cDNA clone with antloncogene activity, p14-6, is found to be able to reduce remarkably the soft agar colony formation ability of part of DT cells and to raise their resistance to the ouabaln toxtcity. This shows that the pt27 peptide can affect the DT cells In a manner similar to the p14- 6 done and provides evidence that the reverting action of the p14-6 to DT cells may be exerted by the expression of its cDNA.
基金This work was supported by a grant from the 863 Program, the National Commission on Science and Technology, China.
文摘A cDNA clone, p14--6, which has an antioncogene activity on the v--Ki--Ras oncogene-transformed malignant cell line DT, was found. This clone was recovered from the revertantR14 cells, which had been isolated by transfections of DT cells with a normal human fibro-blast cDNA library cloned in pcD2, an Okayama-Berg vector. When transfected into DT cells,p14--6 clone gave rise to phenotypical flat reversion in 5--15% of DT transfectant colo-nies. The p14--6--transfected flat cell line, RR, was proven to be a true revertant with signif-icantly reduced malignancy by in ritro and in riro malignancy tests. All other clones recov-ered from R14 cells were unable to cause this reversion. Molecular hybridizations showedthat the p14--6 was inserted into RR genome as tandem repeats, and no structural changewas found in the D--Ki--Ras oncogene in RR genome. These facts suggest that the antioncogeneactivity of the p14--6 clone on the DT cells may be exerted through expression of thecDNA contained in this clone. Possible reasons for the non-reversion of part of DT cells after p14--6 transfection isdiscussed.
文摘用 Northem Blot 方法研究了固真方对老年大鼠肝组织与增殖有关的基因——原癌基因(C-Ha-ras、c-myc)和抗癌基因(P53)表达的影响。结果显示:(1)c-Ha-rds、c-myc 的表达:老年对照组较青年对照组分别降低了61.8％和58.3％;老年用药组较老年对照组分别增高了1.25和0.56倍。(2)P53的表达:老年对照组较青年对照组升高了0.89倍,而老年用药组较老年对照组降低了0.83倍。结果有助于揭示中药固真方补肾益精、延缓衰老作用的分子机理。
