title: Astrocytes induce proliferation of oligodendrocyte progenitor cells via connexin 47-mediated activation of the ERK/Id4 pathway.
abstract: The proliferative ability of oligodendrocyte progenitor cells (OPCs) varied markedly under different culture conditions. Astrocytes (ASTs) have been verified to play a major role in regulating the proliferation of OPCs through direct contact. However, the mechanisms have not been fully clarified. To investigate the effect and mechanism under AST and OPC co-culture conditions, we analyzed all connexins comprehensively in OPCs under OPC mono-culture, AST-secreted cell factor co-culture and AST-OPC direct-contact co-culture, and found that significantly differentially expressed Cx47 was the most significant. To assess whether Cx47 plays a role in proliferation, Cx47 siRNA were conducted. The result indicates that the cell cycle of OPCs was changed, and the cell proliferation was markedly inhibited. Kyoto Encyclopedia of Genes and Genomes (KEGG) predictive analysis suggested that Cx47 regulate cell cycle and proliferation by Ca2+activation of ERK1/2. To verify the prediction, flow cytometry, confocal microscopy, 5-ethynyl-2'-deoxyuridine (EdU), polymerase chain reaction (RT-PCR) and western blot were used. The results show that interference of Cx47 led to decreased Ca2+concentrations, lower p-ERK 1/2 levels, reduced transcription factor inhibitor of DNA binding 4 (Id4) expression, arrested cell cycle and reduced OPCs proliferative ability. Additionally, blocking ERK1/2 signaling caused decreased Id4 expression, arrested cell cycle in G1 phase, and reduced OPCs proliferative ability. In conclusion, ASTs can cause Ca2+signaling activation, ERK1/2 phosphorylation, and Id4 expression stimulation in OPCs, inducing proliferation of these cells, mainly through Cx47.
authors.affiliation: a Laboratory of Stem Cell and Tissue Engineering, Department of Histology and Embryology , Chongqing Medical University , Chongqing , P.R. China.
authors.forename: Zhaoyu
authors.initials: Z
authors.lastname: Liu
authors.affiliation: b Department of Neurosurgery , The First Affiliated Hospital of Chongqing Medical University , Chongqing , P.R. China.
authors.forename: Dan
authors.initials: D
authors.lastname: Xu
authors.affiliation: a Laboratory of Stem Cell and Tissue Engineering, Department of Histology and Embryology , Chongqing Medical University , Chongqing , P.R. China.
authors.forename: Shang
authors.initials: S
authors.lastname: Wang
authors.affiliation: a Laboratory of Stem Cell and Tissue Engineering, Department of Histology and Embryology , Chongqing Medical University , Chongqing , P.R. China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Chen
authors.affiliation: a Laboratory of Stem Cell and Tissue Engineering, Department of Histology and Embryology , Chongqing Medical University , Chongqing , P.R. China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Li
authors.affiliation: a Laboratory of Stem Cell and Tissue Engineering, Department of Histology and Embryology , Chongqing Medical University , Chongqing , P.R. China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Gao
authors.affiliation: a Laboratory of Stem Cell and Tissue Engineering, Department of Histology and Embryology , Chongqing Medical University , Chongqing , P.R. China.
authors.forename: Lu
authors.initials: L
authors.lastname: Jiang
authors.affiliation: a Laboratory of Stem Cell and Tissue Engineering, Department of Histology and Embryology , Chongqing Medical University , Chongqing , P.R. China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Tang
authors.affiliation: a Laboratory of Stem Cell and Tissue Engineering, Department of Histology and Embryology , Chongqing Medical University , Chongqing , P.R. China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Peng
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000166:cytology* / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling; D002453:Cell Cycle; D049109:Cell Proliferation; D018920:Coculture Techniques; D017630:Connexins / Q000378:metabolism*; D003857:Deoxyuridine / Q000031:analogs & derivatives / Q000378:metabolism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D051796:Inhibitor of Differentiation Proteins / Q000378:metabolism*; D020935:MAP Kinase Signaling System; D009836:Oligodendroglia / Q000166:cytology* / Q000378:metabolism; D010766:Phosphorylation; D034741:RNA, Small Interfering / Q000378:metabolism; D017207:Rats, Sprague-Dawley; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism
chemical_list: D017630:Connexins; C490126:Id4 protein, rat; D051796:Inhibitor of Differentiation Proteins; D034741:RNA, Small Interfering; C427305:connexin 47; D048049:Extracellular Signal-Regulated MAP Kinases; C031086:5-ethynyl-2'-deoxyuridine; D002118:Calcium; D003857:Deoxyuridine
keywords: Astrocyte; Cx47; ERK1/2; oligodendrocyte precursor cell; proliferation