Role of NF-κB Binding Sites in the Regulation of Inducible Nitric Oxide Synthase by Tyrosine Kinase

• 영문명: Role of NF-κB Binding Sites in the Regulation of Inducible Nitric Oxide Synthase by Tyrosine Kinase
• 발행기관: 대한생리학회-대한약리학회
• 저자명: Young Sue Ryu Jang Hee Hong Jong Ho Lim So Hyun Bae Ihn Sub Ahn Jeong Ho Seok Jae Heun Lee Gang Min
• 간행물 정보: 『The Korean Journal of Physiology & Pharmacology』제5권 제1호, 55~63쪽, 전체 9쪽
• 주제분류: 의약학 > 의학일반
• 파일형태: PDF
• 발행일자: 2001.01.01

영문 초록

In macrophages, lipopolysaccharide (LPS) alone or in combination with interferon-γ (IFN-γ) has been shown to release a nitric oxide (NO) through the increase of the transcription of the inducible nitric oxide synthase (iNOS) gene. To investigate the exact intracellular signaling pathway of the regulation of iNOS gene transcription by LPS plus IFN-γ, the effects of protein tyrosine kinase (PTK) inhibitor and protein kinase C (PKC) inhibitors on NO production, iNOS mRNA expression, nuclear factor-κB (NF-κB) binding activity and the promoter activity of iNOS gene containing two NF-κB sites have been examined in a mouse macrophage RAW 264.7 cells. LPS or IFN-γ stimulated NO production, and their effect was enhanced synergistically by mixture of LPS and IFN-γ. The PTK inhibitor such as tyrphostin reduced LPS plus IFN-γ-induced NO production, iNOS mRNA expression and NF-κB binding activity. In contrast, PKC inhibitors such as H-7, Ro-318220 and staurosporine did not show any effect on them. In addition, transfection of RAW 264.7 cells with iNOS promoter linked to a CAT reporter gene revealed that tyrphostin inhibited the iNOS promoter activity through the NF-κB binding site, whereas PKC inhibitors did not. Taken together, these suggest that PTK, but not PKC pathway, is involved in the regulation of the iNOS gene transcription through the NF-κB sites of iNOS promoter in RAW 264.7 macrophages by LPS plus IFN-γ.

키워드

Nitric oxide synthase NF-κB binding sites Protein tyrosine kinase Protein kinase C Lipopolysaccharides Macrophages ANOVA analysis of variance DTT dithiothreitol Grp glucose-regulated protein HSP heat shock family of stress proteins Hsp