RRC ID 42982
著者 Inada S, Ikeda Y, Suehiro T, Takata H, Osaki F, Arii K, Kumon Y, Hashimoto K.
タイトル Glucose enhances protein tyrosine phosphatase 1B gene transcription in hepatocytes.
ジャーナル Mol Cell Endocrinol
Abstract Protein tyrosine phosphatase 1B (PTP1B) is a negative regulator of the insulin receptor signal transduction pathway. We investigated the effects of glucose on PTP1B transcription in the human hepatocyte cell line Huh7. Using a reporter gene assay, we found that D-glucose dose-dependently enhanced the PTP1B promoter activity. Real-time PCR demonstrated that D-glucose also increased PTP1B mRNA expression. Protein kinase C (PKC) inhibitors partially but significantly inhibited the transactivation by D-glucose. Mithramycin, a Sp1 inhibitor, completely abrogated this transactivation. The deletion of three possible Sp1 sites in the promoter region of PTP1B significantly reduced the basal promoter activity and transactivation by D-glucose. Sp1 activation by PKC is one of the key mechanisms in the regulation of several gene expressions. Our data suggested that glucose enhanced PTP1B transcription through Sp1 activation by PKC. Increased hepatic PTP1B expression may partly explain glucose toxicity in diabetes.
巻・号 271(1-2)
ページ 64-70
公開日 2007-6-15
DOI 10.1016/j.mce.2007.04.005
PII S0303-7207(07)00156-6
PMID 17509747
MeSH Cell Line Gene Expression Regulation* Genes, Reporter Glucose / metabolism* Hepatocytes / cytology Hepatocytes / physiology* Humans Insulin / metabolism Plicamycin / metabolism Promoter Regions, Genetic Protein Kinase C / antagonists & inhibitors Protein Synthesis Inhibitors / metabolism Protein Tyrosine Phosphatase, Non-Receptor Type 1 Protein Tyrosine Phosphatases / genetics Protein Tyrosine Phosphatases / metabolism* Signal Transduction / physiology Sp1 Transcription Factor / metabolism Transcription, Genetic*
IF 3.871
引用数 13
WOS 分野 ENDOCRINOLOGY & METABOLISM CELL BIOLOGY
リソース情報
ヒト・動物細胞