title: MicroRNA-181c targets Bcl-2 and regulates mitochondrial morphology in myocardial cells.
abstract: Apoptosis is an important mechanism for the development of heart failure. Mitochondria are central to the execution of apoptosis in the intrinsic pathway. The main regulator of mitochondrial pathway of apoptosis is Bcl-2 family which includes pro- and anti-apoptotic proteins. MicroRNAs are small noncoding RNA molecules that regulate gene expression by inhibiting mRNA translation and/or inducing mRNA degradation. It has been proposed that microRNAs play critical roles in the cardiovascular physiology and pathogenesis of cardiovascular diseases. Our previous study has found that microRNA-181c, a miRNA expressed in the myocardial cells, plays an important role in the development of heart failure. With bioinformatics analysis, we predicted that miR-181c could target the 3' untranslated region of Bcl-2, one of the anti-apoptotic members of the Bcl-2 family. Thus, we have suggested that miR-181c was involved in regulation of Bcl-2. In this study, we investigated this hypothesis using the Dual-Luciferase Reporter Assay System. Cultured myocardial cells were transfected with the mimic or inhibitor of miR-181c. We found that the level of miR-181c was inversely correlated with the Bcl-2 protein level and that transfection of myocardial cells with the mimic or inhibitor of miR-181c resulted in significant changes in the levels of caspases, Bcl-2 and cytochrome C in these cells. The increased level of Bcl-2 caused by the decrease in miR-181c protected mitochondrial morphology from the tumour necrosis factor alpha-induced apoptosis.
authors.affiliation: Department of Cardiology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
authors.forename: Hongjiang
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Cardiology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Cardiology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
authors.forename: Hongjie
authors.initials: H
authors.lastname: Chi
authors.affiliation: Department of Cardiology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
authors.forename: Fan
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Department of Cardiology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Department of Cardiology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Cai
authors.affiliation: Department of Cardiology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
authors.forename: Xinchun
authors.initials: X
authors.lastname: Yang
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics; D001483:Base Sequence; D015153:Blotting, Western; D002470:Cell Survival / Q000187:drug effects; D017124:Conserved Sequence / Q000235:genetics; D004272:DNA, Mitochondrial / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000378:metabolism; D051379:Mice; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008929:Mitochondria, Heart / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D051336:Mitochondrial Membranes / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D008969:Molecular Sequence Data; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*; D041681:NIH 3T3 Cells; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics; D014162:Transfection; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D020413:3' Untranslated Regions; D004272:DNA, Mitochondrial; D035683:MicroRNAs; D019253:Proto-Oncogene Proteins c-bcl-2; D014409:Tumor Necrosis Factor-alpha; C485184:enhanced green fluorescent protein; C529100:mirn181 microRNA, mouse; D049452:Green Fluorescent Proteins
keywords: apoptosis; bcl-2; microRNA; mitochondria