Osteopontin and protein kinase C regulate PDLIM2 activation and STAT1 ubiquitination in LPS-treated murine macrophages.

ABSTRACT: The molecular pathways regulating signal transducer and activator of transcription 1 (STAT1) levels in states of inflammation are incompletely understood. The suppressor of cytokine signaling, protein inhibitor of STAT, and SHP-1/2 tyrosine phosphatases ultimately regulate activity of STAT molecules. However, these mechanisms do not degrade STAT proteins. In this regard, using a murine macrophage model of LPS stimulation, we previously demonstrated that osteopontin (OPN) increased STAT1 ubiquitination and 26 S proteasome degradation via the ubiquitin E3 ligase, PDLIM2. In this study, we further characterize OPN-dependent activation of PDLIM2 in a model of LPS-stimulated RAW264.7 murine macrophages. We identify serine 137 as a protein kinase C-phosphorylation site in PDLIM2 that is required

SUBMITTER: Guo H 

PROVIDER: S-EPMC2988383 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature