Inhibition of ubiquitin-proteasome pathway-mediated I kappa B alpha degradation by a naturally occurring antibacterial peptide.

ABSTRACT: Induction of NF-kappaB-dependent gene expression plays an important role in a number of biological processes including inflammation and ischemia-reperfusion injury. However, few attempts aimed at selective regulation of this transcription factor have been successful. We report here that a naturally occurring antibacterial peptide PR39 reversibly binds to the alpha 7 subunit of the 26S proteasome and blocks degradation of NF-kappa B inhibitor I kappa B alpha by the ubiquitin-proteasome pathway without affecting overall proteasome activity. I kappa B alpha phosphorylation and ubiquitination occur normally after PR39 treatment, and binding of valosin-containing proteins is not impaired. The inhibition of I kappa B alpha degradation abolishes induction of NF-kappa B-dependent gene expression i

SUBMITTER: Gao Y 

PROVIDER: S-EPMC314329 | biostudies-literature | 2000 Aug

REPOSITORIES: biostudies-literature