The JI
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     
 

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Levin, E. G.
Right arrow Articles by Santell, L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Levin, E. G.
Right arrow Articles by Santell, L.

The Journal of Immunology, Vol 146, Issue 11 3772-3778, Copyright © 1991 by American Association of Immunologists

ARTICLES

Phosphorylation of an Mr = 29,000 protein by IL-1 is susceptible to partial down-regulation after endothelial cell activation

EG Levin and L Santell
Department of Molecular and Experimental Medicine, Scripps Clinic and Research Foundation, La Jolla, CA 92037.

IL-1 treatment of human endothelial cells leads to the rapid phosphorylation of a Mr = 29,000 (P29) set of proteins to 18 times that of control cultures. Approximately 80% of the phosphorylated P29 (pP29) disappeared within 60 min although the remaining component was stable and remained for at least another 2 h. IL-1R antagonist protein blocked phosphorylation completely. Secondary treatment of IL-1 failed to increase the level of pP29 above that remaining after 1 h although other unrelated agonists that stimulated pP29 generation could. Removal of the cytokine and incubation of the cells in agonist-free medium for 2 h resulted in the total loss of the remaining pP29. Readdition of IL- 1 2 h after washout restimulated P29 phosphorylation but only back to the lower level. Maximum rephosphorylation could not be attained until 16 h after IL-1 removal. Protein kinase inhibitors 1-(5- isoquinolinylsulfonyl)-2-methylpiperazine and staurosporine, the calcium chelators bis(2-amino-5-methylphenoxy)ethane-N,N,N',N'- tetraacetic acid tetraacetoxymethyl ester and EGTA, and the calmodulin inhibitor N-(6-aminohexyl)-1-naphthalene-sulfonamide had no effect on IL-I-induced phosphorylation. However, when cultures were treated with the protein phosphatase inhibitor okadaic acid alone, the level of pP29 increased after 1 h and the presence of okadaic acid during prolonged IL-1 treatment blocked the decline in pP29. The protein synthesis inhibitors puromycin, emetine, and cycloheximide also blocked the decline in pP29 during IL-1 treatment. These data suggest that IL-1- stimulated P29 phosphorylation is made up of two components, one susceptible to prolonged down-regulation even in the absence of the cytokine and one refractory to desensitization but that remains active only in the presence of IL-1. IL-1-induced changes in pP29 levels may be dependent on the relative activities of protein kinase and protein phosphatase activities.


This article has been cited by other articles:


Home page
 J. Biol. Chem.Home page
R. S. Piotrowicz and E. G. Levin
Basolateral Membrane-associated 27-kDa Heat Shock Protein and Microfilament Polymerization
J. Biol. Chem., October 10, 1997; 272(41): 25920 - 25927.
[Abstract] [Full Text] [PDF]

Home page
 Innate ImmunityHome page
S.A. Barber, C.A. Salkowski, M.J. Fultz, P-Y. Perera, R. McNally, and S.N. Vogel
Regulation of gene expression and nitric oxide production in murine macrophages by the serine/threonine phosphatase inhibitor okadaic acid
Innate Immunity, February 1, 1996; 3(1): 19 - 27.
[Abstract] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Website Copyright © 1991 by The American Association of Immunologists, Inc. All rights reserved.
All Contents Copyright © 1991 by The American Association of Immunologists, Inc. All rights reserved.