title: Regulated expression of neurogenic basic helix-loop-helix transcription factors during differentiation of the immortalized neuronal progenitor cell line HC2S2 into neurons.
abstract: Expression of nine neurogenic basic helix-loop-helix (bHLH) transcription factors was examined in an immortalized neuronal progenitor cell line HC2S2, which differentiates into neurons after suppression of the v-myc expression with tetracycline. Expression of MASH-1, NeuroD, NeuroD-related factor (NDRF) and HES-1 was demonstrated in HC2S2 cells by Northern blot analysis using total RNA. Expression of MASH-1 mRNA was downregulated upon differentiation of HC2S2 cells into mature neurons. In contrast, NeuroD and NDRF mRNA expression was maintained all through the differentiation. The expression of HES-1, a negative regulator of the neuronal differentiation, was upregulated temporarily in accordance with the suppression of the v-myc expression and was downregulated upon the differentiation of HC2S2 cells into neurons. The reduced expression of HES-1 mRNA in undifferentiated HC2S2 cells may be explained by the transcriptional suppression of HES-1 by the myc oncoprotein. The above data imply that both HES-1 and MASH-1 need to be downregulated at the time of accomplishment of the terminal differentiation into mature neurons and that NeuroD and NDRF participate in the regulatory process of the terminal differentiation in combination.
authors.affiliation: Department of Neurosurgery, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ohtsuka
authors.forename: M
authors.initials: M
authors.lastname: Asahi
authors.forename: N
authors.initials: N
authors.lastname: Matsuura
authors.forename: H
authors.initials: H
authors.lastname: Kikuchi
authors.forename: M
authors.initials: M
authors.lastname: Hojo
authors.forename: R
authors.initials: R
authors.lastname: Kageyama
authors.forename: H
authors.initials: H
authors.lastname: Ohkubo
authors.forename: M
authors.initials: M
authors.lastname: Hoshimaru
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins; D015152:Blotting, Northern; D002454:Cell Differentiation / Q000235:genetics; D002461:Cell Line, Transformed / Q000737:chemistry / Q000166:cytology / Q000502:physiology; D004268:DNA-Binding Proteins / Q000032:analysis / Q000235:genetics; D005455:Fluorescent Antibody Technique; D019922:GAP-43 Protein / Q000032:analysis / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D018257:Helix-Loop-Helix Motifs / Q000235:genetics*; D006624:Hippocampus / Q000166:cytology; D018398:Homeodomain Proteins / Q000032:analysis / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000235:genetics; D009474:Neurons / Q000737:chemistry / Q000166:cytology* / Q000502:physiology; D009479:Neuropeptides / Q000032:analysis / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D012097:Repressor Proteins / Q000032:analysis / Q000235:genetics; D013234:Stem Cells / Q000737:chemistry / Q000166:cytology* / Q000502:physiology; D000072056:Transcription Factor HES-1; D014157:Transcription Factors / Q000032:analysis / Q000235:genetics*; D029867:Xenopus Proteins
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D019922:GAP-43 Protein; D018398:Homeodomain Proteins; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; D012333:RNA, Messenger; D012097:Repressor Proteins; D000072056:Transcription Factor HES-1; D014157:Transcription Factors; D029867:Xenopus Proteins; C499318:Ascl1 protein, rat; C500943:Atoh1 protein, mouse; C489734:Hes1 protein, mouse; C489735:Hes1 protein, rat; C083910:Hes3 protein, rat; C489685:Hes5 protein, mouse; C489686:Hes5 protein, rat; C490925:NEUROD2 protein, human; C490553:NEUROD6 protein, human; C490924:Neurod2 protein, rat; C110701:Neurod6 protein, mouse; C490554:Neurod6 protein, rat; C101907:neurogenin, Xenopus; C077478:HES5 protein, human; C093564:Neurogenic differentiation factor 1