This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Wei Zhu Articles by Jiahuai Han Search for Related Content PubMed Articles by Wei Zhu, Articles by Jiahuai Han, Social Bookmarking                         What's this?

Co-ordinated regulation of TNF expression by multiple MAP kinase pathways

Department of Immunology, The Scripps Research Institute, La Jolla, California, USA

Jocelyn S. Downey

Department of Immunology, The Scripps Research Institute, La Jolla, California, USA

Yingqiu Li

Department of Immunology, The Scripps Research Institute, La Jolla, California, USA

Jiahuai Han

Department of Immunology, The Scripps Research Institute, La Jolla, California, USA

Four MAP kinase pathways are currently believed to be activated in LPS stimulated macrophages: the ERK, JNK/SAPK, p38 and BMK/ERK5 pathways. We have evaluated the effect of each MAP kinase pathway and the combinational effect of these MAP kinase pathways on TNF gene expression. By co-expressing dominant active mutants of different MAP kinase activators with a TNF reporter gene, we have demonstrated that activation of a signal MAP kinase pathway produces only a modest effect on TNF gene expression. Interestingly, a dramatic co-operative effect on TNF gene expression was observed when all of the four MAP kinase pathways were activated. We have shown that this MAP kinase-induced TNF gene expression is not mediated by known cis-elements such as Egr-1, CRE, kB, AP-1, or AP-2, but by, as yet unidentified, MAP kinase responsive elements in a 100 bp region immediately upstream of the transcription initiation site. In addition to their participation in the transcriptional control of TNF gene expression, activation of MAP kinases regulates TNF by overcoming the repressive effect of the AU-rich element (ARE) located in the 3'untranslated region. Thus, MAP kinase pathways co-ordinate with each other to regulate TNF gene expression at multiple levels.

Journal of Endotoxin Research, Vol. 5, No. 4, 239-243 (1999)
DOI: 10.1177/09680519990050040201


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?