Altered subcellular distribution of nucleolar protein fibrillarin by actinomycin D in HEp-2 cells  

作　　者：MinCHEN PingJIANG 

机构地区：[1]ResearchCenterofBasicMedicine,SchoolofMedicine,JiangsuUniversity,Zhenjiang212001,China

出　　处：《Acta Pharmacologica Sinica》2004年第7期902-906,共5页中国药理学报（英文版）

基　　金：Supported by the Doctoral Foundation of Jiangsu University No 2681280006.

摘　　要：AIM: To study the effects of actinomycin D on subcellular distribution ofnucleolar protein fibrillarin in HEp-2 (human esophageal epithelial type 2) cells, and molecularmechanisms for maintenance of fibrillarin in nucleolus. METHODS: Indirect immunofluorescence assaywas employed to investigate subcellular distribution of nucleolar protein fibrillarin andimmunoblotting analysis was used to detect the total cellular amount of fibrillarin. RESULTS:Control cells with no drug treatment showed bright clumpy nucleolar staining, which indicated thatfibrillarin decorated the nucleolus only. Treatment with actinomycin D caused dislocation offibrillarin from nucleoli to nucleoplasm with numerous stained small nucleoplasmic entities.Immunoblotting showed that neither total cellular amount of fibrillarin nor the integrity offibrillarin was changed upon the treatment. The dislocation of fibrillarin in cells treated at alower concentration (0.05 mg/L) of actinomycin D, was totally reversible after removal of the drugfrom the medium. However, this reversion was not observed at a high drug concentration (1 mg/L).CONCLUSION: Actinomycin D induced dislocation of fibrillarin from nucleoli to nucleoplasm in HEp-2cells. The retention of fibrillarin within the nucleolus was related to active RNA synthesis.AIM: To study the effects of actinomycin D on subcellular distribution ofnucleolar protein fibrillarin in HEp-2 (human esophageal epithelial type 2) cells, and molecularmechanisms for maintenance of fibrillarin in nucleolus. METHODS: Indirect immunofluorescence assaywas employed to investigate subcellular distribution of nucleolar protein fibrillarin andimmunoblotting analysis was used to detect the total cellular amount of fibrillarin. RESULTS:Control cells with no drug treatment showed bright clumpy nucleolar staining, which indicated thatfibrillarin decorated the nucleolus only. Treatment with actinomycin D caused dislocation offibrillarin from nucleoli to nucleoplasm with numerous stained small nucleoplasmic entities.Immunoblotting showed that neither total cellular amount of fibrillarin nor the integrity offibrillarin was changed upon the treatment. The dislocation of fibrillarin in cells treated at alower concentration (0.05 mg/L) of actinomycin D, was totally reversible after removal of the drugfrom the medium. However, this reversion was not observed at a high drug concentration (1 mg/L).CONCLUSION: Actinomycin D induced dislocation of fibrillarin from nucleoli to nucleoplasm in HEp-2cells. The retention of fibrillarin within the nucleolus was related to active RNA synthesis.

关 键 词：DACTINOMYCIN nuclear proteins fluorescence antibody technique immunoblotting 

分 类 号：R392[医药卫生—免疫学]