Chromatin is the primary carrier of epigenetic information in higher eukaryotes. AtCYP71 contains both cyclophilin domain and WD40 repeats. Loss of AtCYP71 function causes drastic pleiotropic phenotypic defects. Here,...Chromatin is the primary carrier of epigenetic information in higher eukaryotes. AtCYP71 contains both cyclophilin domain and WD40 repeats. Loss of AtCYP71 function causes drastic pleiotropic phenotypic defects. Here, we show that AtCYP71 physically interacts with FAS1 and LHP1, respectively, to modulate their distribution on chromatin. The Ihpl cyp71 double mutant showed more severe phenotypes than the single mutants, suggesting that AtCYP71 and LHP1 synergistically control plant development. Such synergism was in part illustrated by the observation that LHP1 association with its specific target loci requires AtCYP71 function. We also demonstrate that AtCYP71 physically interacts with FAS1 and is indispensable for FAS1 targeting to the KNAT1 locus. Together, our data suggest that AtCYP71 is involved in fundamental processes of chromatin assembly and histone modification in plants.展开更多
Background Bone morphogenetic protein-6 （BMP-6） is closely correlated with tumor differentiation and skeletal metastasis. Estrogen is considered as a stimulant for the initiation and promotion of breast cancer. Prev...Background Bone morphogenetic protein-6 （BMP-6） is closely correlated with tumor differentiation and skeletal metastasis. Estrogen is considered as a stimulant for the initiation and promotion of breast cancer. Previous studies demonstrated that 17β-estadiol （E2） can selectively increase the expression of BMP-6. This experiment is designed to detect the molecular mechanism of estrogen activating BMP-6 gene transcription in human estrogen receptor positive （ER ^＋） breast cancer cell line MCF-7. Methods After the treatment of MCF-7 cells with E2 at different concentrations （ 10^-11 mol/L, 10.9 mol/L, 10.7 mol/L）, the BMP-6 expression level was examined through real-time polymerase chain reaction. Through restriction enzyme digestion, human BMP-6 1.2 kb long promoter, BMP-6 0. 7 kb long promoter was cloned into pGL-3 basic vector; after the treatment with 10^-7 mol/L E2, luciferase activities of the two promoters were detected. Site-directed mutagenesis was performed to obtain the mutant forms of estrogen response element half- site （ 1/2 ERE） element and Spl sites in the BMP-6 promoter, the activities of these mutant form promoters were detected following the methods mentioned above. Chromatin immunoprecipitation （CHIP） assay was also used to confirm the binding of estrogen receptor a （ERα） on BMP-6 promoter in the presence of E2. Results E2 dose dependently increased BMP-6 mRNA expression in human ER ^＋ breast cancer cell line MCF-7. At a dose of 10^-7 mol/L E2, human BMP-6 1.2 kb promoter activity was increased by 90% compared with the control group treated with ethanol （P 〈 0. 05 ）. Both the 1/2 ERE response element mutant form and the Spl site mutant form of the BMP-6 promoter abolished the activation of the BMP-6 promoter＇ s response to E2. Through ChIP assay, the binding of ERot on 1/2 ERE response element in BMP-6 promoter was further validated. Conclusion Estrogen induces BMP-6 expression in human ER^＋ breast cancer cell line MCF-7 receptor ERα binding on 1/2 ERE展开更多
文摘Chromatin is the primary carrier of epigenetic information in higher eukaryotes. AtCYP71 contains both cyclophilin domain and WD40 repeats. Loss of AtCYP71 function causes drastic pleiotropic phenotypic defects. Here, we show that AtCYP71 physically interacts with FAS1 and LHP1, respectively, to modulate their distribution on chromatin. The Ihpl cyp71 double mutant showed more severe phenotypes than the single mutants, suggesting that AtCYP71 and LHP1 synergistically control plant development. Such synergism was in part illustrated by the observation that LHP1 association with its specific target loci requires AtCYP71 function. We also demonstrate that AtCYP71 physically interacts with FAS1 and is indispensable for FAS1 targeting to the KNAT1 locus. Together, our data suggest that AtCYP71 is involved in fundamental processes of chromatin assembly and histone modification in plants.
文摘Background Bone morphogenetic protein-6 （BMP-6） is closely correlated with tumor differentiation and skeletal metastasis. Estrogen is considered as a stimulant for the initiation and promotion of breast cancer. Previous studies demonstrated that 17β-estadiol （E2） can selectively increase the expression of BMP-6. This experiment is designed to detect the molecular mechanism of estrogen activating BMP-6 gene transcription in human estrogen receptor positive （ER ^＋） breast cancer cell line MCF-7. Methods After the treatment of MCF-7 cells with E2 at different concentrations （ 10^-11 mol/L, 10.9 mol/L, 10.7 mol/L）, the BMP-6 expression level was examined through real-time polymerase chain reaction. Through restriction enzyme digestion, human BMP-6 1.2 kb long promoter, BMP-6 0. 7 kb long promoter was cloned into pGL-3 basic vector; after the treatment with 10^-7 mol/L E2, luciferase activities of the two promoters were detected. Site-directed mutagenesis was performed to obtain the mutant forms of estrogen response element half- site （ 1/2 ERE） element and Spl sites in the BMP-6 promoter, the activities of these mutant form promoters were detected following the methods mentioned above. Chromatin immunoprecipitation （CHIP） assay was also used to confirm the binding of estrogen receptor a （ERα） on BMP-6 promoter in the presence of E2. Results E2 dose dependently increased BMP-6 mRNA expression in human ER ^＋ breast cancer cell line MCF-7. At a dose of 10^-7 mol/L E2, human BMP-6 1.2 kb promoter activity was increased by 90% compared with the control group treated with ethanol （P 〈 0. 05 ）. Both the 1/2 ERE response element mutant form and the Spl site mutant form of the BMP-6 promoter abolished the activation of the BMP-6 promoter＇ s response to E2. Through ChIP assay, the binding of ERot on 1/2 ERE response element in BMP-6 promoter was further validated. Conclusion Estrogen induces BMP-6 expression in human ER^＋ breast cancer cell line MCF-7 receptor ERα binding on 1/2 ERE
