1. Fibrogenic Activity of MECP2 Is Regulated by Phosphorylation in Hepatic Stellate Cells
- Author
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Amber Knox, Jelena Mann, Marina García-Macia, Laura Sabater, Eva Morán-Salvador, Agata Page, Fiona Oakley, Marco Y W Zaki, Saimir Luli, Ashwin Sivaharan, and Derek A. Mann
- Subjects
0301 basic medicine ,Male ,WT, wild type ,DNA Repair ,Methyl-CpG-Binding Protein 2 ,Liver Cirrhosis, Experimental ,Transcriptome ,BrdU, bromodeoxyuridine ,MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide ,0302 clinical medicine ,lncRNA ,MCM, maintenance protein complex ,PCA, principal components analysis ,CCl4, carbon tetrachloride ,Serine ,Epigenetic Factor ,Phosphorylation ,APAP, N-acetyl-ρ-aminophen ,Carbon Tetrachloride ,TGF, transforming growth factor ,Cells, Cultured ,Mice, Knockout ,Kinase ,Gastroenterology ,Long non-coding RNA ,mRNA, messenger RNA ,3. Good health ,Cell biology ,ECM, extracellular matrix ,MMP, matrix metalloproteinase ,030211 gastroenterology & hepatology ,Collagen ,Chemical and Drug Induced Liver Injury ,HSC, hepatic stellate cells ,Signal Transduction ,DNA Replication ,congenital, hereditary, and neonatal diseases and abnormalities ,α-SMA, α–smooth muscle actin ,DNA repair ,Biology ,SEM, standard error of the mean ,KEGG, Kyoto Encyclopedia of Genes and Genomes ,Article ,03 medical and health sciences ,Minichromosome maintenance ,mental disorders ,Hepatic Stellate Cells ,Animals ,Gene ,Acetaminophen ,Cell Proliferation ,IPA, Ingenuity Pathway Analysis ,Myofibroblast ,Hepatology ,MCM ,qRT-PCR, quantitative reverse-transcription polymerase chain reaction ,nervous system diseases ,IL, interleukin ,Mice, Inbred C57BL ,030104 developmental biology ,siRNA, small interfering RNA ,Hepatic stellate cell ,lncRNA, long noncoding RNA - Abstract
Background & Aims Methyl-CpG binding protein 2, MECP2, which binds to methylated regions of DNA to regulate transcription, is expressed by hepatic stellate cells (HSCs) and is required for development of liver fibrosis in mice. We investigated the effects of MECP2 deletion from HSCs on their transcriptome and of phosphorylation of MECP2 on HSC phenotype and liver fibrosis. Methods We isolated HSCs from Mecp2–/y mice and wild-type (control) mice. HSCs were activated in culture and used in array analyses of messenger RNAs and long noncoding RNAs. Kyoto Encyclopedia of Genes and Genomes pathway analyses identified pathways regulated by MECP2. We studied mice that expressed a mutated form of Mecp2 that encodes the S80A substitution, MECP2S80, causing loss of MECP2 phosphorylation at serine 80. Liver fibrosis was induced in these mice by administration of carbon tetrachloride, and liver tissues and HSCs were collected and analyzed. Results MECP2 deletion altered expression of 284 messenger RNAs and 244 long noncoding RNAs, including those that regulate DNA replication; are members of the minichromosome maintenance protein complex family; or encode CDC7, HAS2, DNA2 (a DNA helicase), or RPA2 (a protein that binds single-stranded DNA). We found that MECP2 regulates the DNA repair Fanconi anemia pathway in HSCs. Phosphorylation of MECP2S80 and its putative kinase, HIPK2, were induced during transdifferentiation of HSCs. HSCs from MECP2S80 mice had reduced proliferation, and livers from these mice had reduced fibrosis after carbon tetrachloride administration. Conclusions In studies of mice with disruption of Mecp2 or that expressed a form of MECP2 that is not phosphorylated at S80, we found phosphorylation of MECP2 to be required for HSC proliferation and induction of fibrosis. In HSCs, MECP2 regulates expression of genes required for DNA replication and repair. Strategies to inhibit MECP2 phosphorylation at S80 might be developed for treatment of liver fibrosis.
- Published
- 2018