title: Role of Npm1 in proliferation, apoptosis and differentiation of neural stem cells.
abstract: Neural tube defects (NTDs) are among the most prevalent and serious congenital malformations. And one notable teratogen that can induce NTDs is fetal exposure to hyperthermia. In our previous study, by suppression subtractive hybridization (SSH), we identified several differentially expressed genes in hyperthermia-induced NTDs. Nucleophosmin (Npm1), a multifunctional nucleolar protein, was one of the downregulated genes. For functional analysis of Npm1, we employed small interference RNA (siRNA) mediated gene silencing method with neural stem cells (NSCs). The siRNA successfully suppressed Npm1 expression at both mRNA and protein levels. As a result, suppression of Npm1 in NSCs decreased cell proliferation rate, increased apoptosis occurrence but did not seem to affect cell differentiation. Further study revealed that there was increase of p53 and p21 protein after Npm1 suppression. Taken together, our results suggest that suppression of Npm1 in NSCs inhibits cell proliferation, induces apoptosis through p53 pathway but does not affect cell differentiation.
authors.affiliation: Institute of Histology and Embryology, Medical School of Shandong University, Wenhuaxilu 44, Jinan, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Qing
authors.forename: Gao
authors.initials: G
authors.lastname: Yingmao
authors.forename: Bing
authors.initials: B
authors.lastname: Lujun
authors.forename: Li
authors.initials: L
authors.lastname: Shaoling
mesh_terms: D000818:Animals; D017304:Annexin A5 / Q000378:metabolism; D017209:Apoptosis / Q000235:genetics* / Q000502:physiology*; D015153:Blotting, Western; D002454:Cell Differentiation / Q000235:genetics* / Q000502:physiology*; D049109:Cell Proliferation / Q000187:drug effects*; D006224:Cricetinae; D005260:Female; D016158:Genes, p53; D005904:Glial Fibrillary Acidic Protein / Q000096:biosynthesis / Q000235:genetics; D007150:Immunohistochemistry; D008647:Mesocricetus; D019950:Mitogen-Activated Protein Kinase 1 / Q000096:biosynthesis / Q000235:genetics; D009474:Neurons / Q000502:physiology*; D009687:Nuclear Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D000090243:Nucleophosmin; D011247:Pregnancy; D034741:RNA, Small Interfering / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013234:Stem Cells / Q000502:physiology*; D013778:Tetrazolium Salts; D013844:Thiazoles
chemical_list: D017304:Annexin A5; D005904:Glial Fibrillary Acidic Protein; D009687:Nuclear Proteins; D034741:RNA, Small Interfering; D013778:Tetrazolium Salts; D013844:Thiazoles; D000090243:Nucleophosmin; D019950:Mitogen-Activated Protein Kinase 1; C022616:thiazolyl blue