GSBS Dissertations and Theses

Title

The c-Jun NH₂-Terminal Kinase Regulates Jun in vitro and in vivo during the Process of Dorsal Closure: A Dissertation

Approval Date

December 1997

Document Type

Doctoral Dissertation

Department

Graduate School of Biomedical Sciences, Biochemistry & Molecular Biology

Subjects

JNK Mitogen-Activated Protein Kinases; Proto-Oncogene Proteins c-jun; Signal Transduction; Drosophila Proteins; Academic Dissertations; Dissertations, UMMS

Abstract

Tyrosine phosphorylation of proteins by protein tyrosine kinases is an important step in initiating mitogenic signal transduction pathways. The receptor tyrosine kinases represent a class of protein kinases that employ phosphorylation cascades to transmit a signal generated at the cell surface. The AP-1 transcription factor is a common target of receptor tyrosine kinase activation, transformation by Ras-like proteins and activation of the MAP kinase pathway. The AP-1 complex contains a dimer of Jun proteins or a heterodimer of Jun and Fos or other bZip proteins. The transcriptional activation of Jun is enhanced by phosphorylation on residues Ser-63 and Ser-73. Therefore, identifying the regulatory proteins kinases of Jun would be an important link in signaling from the upstream cell surface events to downstream events, such as gene expression. The JNK1 protein kinase was identified and phosphorylates c-Jun at these sites. The JNK1 protein is a member of the JNK group of protein kinases, which are activated in response to UV treatment. JNK1 is the 46 kDa isoform, and the isolation of the 55 kDa isoform is described in this thesis. Furthermore, a role for JNK was established in Drosophila. Drosphila JNK (DJNK) is essential for the process of dorsal closure. The JNK protein kinases are involved in cytokine signaling, response to environmental stress and development.

Comments

In the process of seeking author's permission to provide full text.

Rights and Permissions

Copyright is held by the author, with all rights reserved.

This document is currently not available here.

Share

COinS