title: Inhibitor of DNA binding 1 (Id1) induces differentiation and proliferation of mouse embryonic carcinoma P19CL6 cells.
abstract: The inhibitor of DNA binding (Id) family of genes encodes negative regulators of basic helix-loop-helix transcription factors and has been implicated in such diverse cellular processes as differentiation, proliferation, apoptosis and migration. Id knockout mouse embryos display multiple cardiac defects but the specific role of Id1 in cardiac differentiation is unclear. In the present study, we investigated the function of Id1 in DMSO-induced P19CL6 cells, a widely-accepted cell model of cardiac differentiation. We found that Id1 was upregulated during the cardiac differentiation of P19CL6 cells. The expression of cardiac specific marker genes, Gata4, α-MHC and ISL1, was upregulated in P19CL6 cells stably transfected with Id1 (P19CL6-Id1) during cardiac differentiation. The overexpression of Id1 reduced the number of cells in G1 phase and increased the cell population in G2, M and S phases, while knockdown of Id1 increased the number of cells in G1 phase from 48.6 ± 2.51% to 62.2 ± 1.52% at day 0 of cardiac induction, and from 52.5 ± 3.41% to 63.7 ± 1.02% at day 3 after cardiac induction, indicating that Id1 promoted proliferation of P19CL6 cells. Luciferase assays showed that the activity of TOP flash was higher in P19CL6-Id1 cells than wildtype P19CL6 cells, while Id1 expression was also upregulated in P19CL6 cells treated with Wnt3a or LiCl. This indicates that there may be positive feedback between Id1 and Wnt signaling which plays an important role in cardiac differentiation.
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education of China, Peking University, 38 Xueyuan Road, 100191 Beijing, China.
authors.forename: Qingzhen
authors.initials: Q
authors.lastname: Meng
authors.forename: Zhuqing
authors.initials: Z
authors.lastname: Jia
authors.forename: Weiping
authors.initials: W
authors.lastname: Wang
authors.forename: Binhong
authors.initials: B
authors.lastname: Li
authors.forename: Kangtao
authors.initials: K
authors.lastname: Ma
authors.forename: Chunyan
authors.initials: C
authors.lastname: Zhou
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000235:genetics; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D050991:GATA4 Transcription Factor / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D055785:Gene Knockdown Techniques; D006321:Heart / Q000196:embryology*; D018398:Homeodomain Proteins / Q000235:genetics; D051798:Inhibitor of Differentiation Protein 1 / Q000235:genetics / Q000378:metabolism*; D060850:LIM-Homeodomain Proteins; D018021:Lithium Chloride / Q000494:pharmacology; D051379:Mice; D032386:Myoblasts, Cardiac / Q000166:cytology* / Q000378:metabolism*; D038081:Organogenesis / Q000187:drug effects / Q000235:genetics*; D014157:Transcription Factors; D051153:Wnt Proteins / Q000378:metabolism / Q000494:pharmacology; D060508:Wnt3 Protein; D060509:Wnt3A Protein
chemical_list: D050991:GATA4 Transcription Factor; C484171:Gata4 protein, mouse; D018398:Homeodomain Proteins; C497455:Idb1 protein, mouse; D051798:Inhibitor of Differentiation Protein 1; D060850:LIM-Homeodomain Proteins; D014157:Transcription Factors; D051153:Wnt Proteins; D060508:Wnt3 Protein; D060509:Wnt3A Protein; C555511:Wnt3a protein, mouse; C063843:insulin gene enhancer binding protein Isl-1; D018021:Lithium Chloride