Novel function of neuronal PAS domain protein 1 in erythropoietin expression in neuronal cells.
The basic helix loop helix-PAS (bHLH-PAS) transcription factors have diverse roles in physiologic responses to the environment and in early development. One bHLH-PAS protein, neuronal PAS domain protein 1 (NPAS1), is reported to be expressed only in the central nervous system beginning at the late embryonic stage, but its function is unknown. Using an anti-NPAS1 antibody, we have shown that NPAS1 expression in cerebral cortex was observed first around embryonic Day 16.5 (E16.5) and was then dispersed throughout the region as cortical development progressed. From the similarity with hypoxia-inducible factor-1alpha (HIF-1alpha), we investigated whether NPAS1 regulates transcription of erythropoietin (EPO), which is the target of HIF-1alpha and is expressed in the brain during the early developmental stage. In the present study, we have shown that NPAS1 binds to the enhancer region of Epo in vivo. A luciferase reporter assay revealed a repressive effect of NPAS1 on hypoxia-responsive element-regulated gene expression. These results raise the possibility that NPAS1 plays a role in late central nervous system development by modulating EPO expression in response to cellular oxygen level.
Ohsawa
Shizue
S
Department of Genetics, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo, Japan.
Hamada
Shun
S
Kakinuma
Yoshihiko
Y
Yagi
Takeshi
T
Miura
Masayuki
M
D000818:Animals; D000831:Animals, Newborn; D051784:Aryl Hydrocarbon Receptor Nuclear Translocator; D051792:Basic Helix-Loop-Helix Proteins; D015153:Blotting, Western / Q000379:methods; D001921:Brain / Q000033:anatomy & histology / Q000196:embryology / Q000378:metabolism; D015687:Cell Hypoxia / Q000502:physiology; D002460:Cell Line; D002843:Chromatin / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D003676:Deferoxamine / Q000494:pharmacology; D004622:Embryo, Mammalian; D004921:Erythropoietin / Q000378:metabolism*; D015870:Gene Expression / Q000502:physiology; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D049452:Green Fluorescent Proteins / Q000378:metabolism; D018257:Helix-Loop-Helix Motifs / Q000502:physiology*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D047468:Immunoprecipitation / Q000379:methods; D007502:Iron Chelating Agents / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000276:immunology / Q000502:physiology*; D009474:Neurons / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis; D018336:Receptors, Aryl Hydrocarbon / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013194:Staining and Labeling / Q000379:methods; D014157:Transcription Factors / Q000737:chemistry / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D014162:Transfection / Q000379:methods
D051784:Aryl Hydrocarbon Receptor Nuclear Translocator; D051792:Basic Helix-Loop-Helix Proteins; D002843:Chromatin; D004268:DNA-Binding Proteins; D003676:Deferoxamine; D004921:Erythropoietin; D049452:Green Fluorescent Proteins; D007502:Iron Chelating Agents; D008869:Microtubule-Associated Proteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D018336:Receptors, Aryl Hydrocarbon; D014157:Transcription Factors; C497396:ARNT protein, human; C497397:Arnt protein, mouse; C489787:MAP2 protein, rat; C104263:NPAS1 protein, human; C512770:Npas1 protein, mouse