{"title":"选择性因子1失活对分化骨髓白血病细胞RNA聚合酶I转录的抑制作用。","authors":"L Comai, Y Song, C Tan, T Bui","doi":"","DOIUrl":null,"url":null,"abstract":"<p><p>Transcription by RNA polymerase I (pol I) regulates the rate of ribosome biogenesis and the biosynthetic potential of the cell; therefore, it plays an important role in the control of cell growth. Differentiation of the human promyelocytic leukemic cell line U937 is accompanied by drastic decreases in pol I transcriptional activity. We have used cell-free extracts prepared from undifferentiated and differentiated U937 cells to investigate the molecular mechanisms responsible for this inhibitory process. Our analysis indicates that the activity of the TATA binding protein (TBP)/TBP-associated factor (TAF) complex selectivity factor 1 (SL1), one of the factors required for accurate and promoter-specific transcription by RNA pol I, is severely repressed in differentiated U937 cells. Moreover, the reduction in SL1 activity is not a consequence of a decrease in SL1, because there is no detectable difference in the abundance of TBP or TAFs before and after U937 cell differentiation. In conclusion, our results indicate that the selectivity factor SL1 is an important target for the regulation of pol I transcription during cell differentiation.</p>","PeriodicalId":9753,"journal":{"name":"Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research","volume":"11 1","pages":"63-70"},"PeriodicalIF":0.0000,"publicationDate":"2000-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Inhibition of RNA polymerase I transcription in differentiated myeloid leukemia cells by inactivation of selectivity factor 1.\",\"authors\":\"L Comai, Y Song, C Tan, T Bui\",\"doi\":\"\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Transcription by RNA polymerase I (pol I) regulates the rate of ribosome biogenesis and the biosynthetic potential of the cell; therefore, it plays an important role in the control of cell growth. Differentiation of the human promyelocytic leukemic cell line U937 is accompanied by drastic decreases in pol I transcriptional activity. We have used cell-free extracts prepared from undifferentiated and differentiated U937 cells to investigate the molecular mechanisms responsible for this inhibitory process. Our analysis indicates that the activity of the TATA binding protein (TBP)/TBP-associated factor (TAF) complex selectivity factor 1 (SL1), one of the factors required for accurate and promoter-specific transcription by RNA pol I, is severely repressed in differentiated U937 cells. Moreover, the reduction in SL1 activity is not a consequence of a decrease in SL1, because there is no detectable difference in the abundance of TBP or TAFs before and after U937 cell differentiation. In conclusion, our results indicate that the selectivity factor SL1 is an important target for the regulation of pol I transcription during cell differentiation.</p>\",\"PeriodicalId\":9753,\"journal\":{\"name\":\"Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research\",\"volume\":\"11 1\",\"pages\":\"63-70\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2000-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cell growth & differentiation : the molecular biology journal of the American Association for Cancer Research","FirstCategoryId":"1085","ListUrlMain":"","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
摘要
RNA聚合酶I (pol I)的转录调节核糖体的生物发生速率和细胞的生物合成潜能;因此,它在控制细胞生长中起着重要的作用。人早幼粒细胞白血病细胞系U937的分化伴随着pol I转录活性的急剧下降。我们使用未分化和分化的U937细胞制备的无细胞提取物来研究这种抑制过程的分子机制。我们的分析表明,TATA结合蛋白(TBP)/TBP相关因子(TAF)复合选择因子1 (SL1)的活性在分化的U937细胞中受到严重抑制,该因子是RNA pol I准确和启动子特异性转录所需的因子之一。此外,SL1活性的降低并不是SL1减少的结果,因为在U937细胞分化前后,TBP或TAFs的丰度没有可检测到的差异。综上所述,我们的研究结果表明,选择性因子SL1是调控细胞分化过程中pol I转录的重要靶点。
Inhibition of RNA polymerase I transcription in differentiated myeloid leukemia cells by inactivation of selectivity factor 1.
Transcription by RNA polymerase I (pol I) regulates the rate of ribosome biogenesis and the biosynthetic potential of the cell; therefore, it plays an important role in the control of cell growth. Differentiation of the human promyelocytic leukemic cell line U937 is accompanied by drastic decreases in pol I transcriptional activity. We have used cell-free extracts prepared from undifferentiated and differentiated U937 cells to investigate the molecular mechanisms responsible for this inhibitory process. Our analysis indicates that the activity of the TATA binding protein (TBP)/TBP-associated factor (TAF) complex selectivity factor 1 (SL1), one of the factors required for accurate and promoter-specific transcription by RNA pol I, is severely repressed in differentiated U937 cells. Moreover, the reduction in SL1 activity is not a consequence of a decrease in SL1, because there is no detectable difference in the abundance of TBP or TAFs before and after U937 cell differentiation. In conclusion, our results indicate that the selectivity factor SL1 is an important target for the regulation of pol I transcription during cell differentiation.