衰老人胚肺成纤维细胞核转录活性的研究

Age-related changes in RNA synthesis in isolated human fetal lung fibroblast(2BS) nuclei

目的研究人胚肺成纤维细胞（简称２ＢＳ）核体外转录活性与代龄的关系。方法用３ＨＵＴＰ掺入法研究不同代龄２ＢＳ细胞核体外转录活性。结果衰老２ＢＳ细胞核转录活性较年轻组下降３３％（Ｐ＜００１），其催化ｒＲＮＡ和ｔＲＮＡ合成的ＲＮＡ聚合酶（ＲＮＰ）Ⅰ和Ⅲ的转录活性下降２４％（Ｐ＜００５），催化合成ｍＲＮＡ的ＲＮＰⅡ转录活性下降３８％（Ｐ＜００１）；衰老２ＢＳ细胞核内ＲＮＡ被转运至核外的量为总合成量的２９％，明显低于年轻细胞组的４５％（Ｐ＜００１）。结论衰老２ＢＳ细胞核转录活性的下降可能与其ＲＮＰ的活性与ＲＮＡ的转运水平下降有关。

By means of incorporation of 3H UTP,changes in RNA synthesis of nuclei were determined at senescent human diploid fibroblast(2BS). It was found that the rate of RNA synthesis of senescent cell nuclei decreased 33% in comparison with young cell. Using α amanitin to preferentiallly inhibit the different types of RNA polymerases reponsible for the three classes of RNA, the synthesis of RNA and tRNA by polymerase Ⅰ+Ⅲ decreased 24%, the synthesis of mRNA by polymerase Ⅱ decreased 38% with aging,while with significant difference statistically. The transport of RNA from nuclei to cytoplasm was examined, a reduction was observed with aging.