Format

Send to:

Choose Destination
See comment in PubMed Commons below
EMBO Rep. 2006 Oct;7(10):1023-9. Epub 2006 Aug 4.

Glucocorticoids cause rapid dissociation of a T-cell-receptor-associated protein complex containing LCK and FYN.

Author information

  • 1Laboratory of Experimental Internal Medicine, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands. m.lowenberg@amc.uva.nl

Abstract

Although glucocorticoid (GC)-induced nongenomic effects have been reported, the underlying mechanisms remain unexplained. We previously described that lymphocyte-specific protein tyrosine kinase (LCK) and FYN oncogene related to SRC, FGR, YES (FYN) mediate GC-induced inhibition of T-cell-receptor (TCR) signalling. Here we characterize the underlying molecular mechanism. The present study shows that the GC receptor is part of a TCR-linked multiprotein complex containing heat-shock protein (HSP)90, LCK and FYN, which is essential for TCR-dependent LCK/FYN activation. Experiments with cells transfected with GC-receptor short interfering RNA (siRNA) showed that the GC receptor is an essential component of the TCR signalling complex. Short-term GC treatment induces dissociation of this protein complex, resulting in impaired TCR signalling as a consequence of abrogated LCK/FYN activation. HSP90siRNA-transfected cells are not able to assemble this TCR-associated multiprotein complex, and accordingly HSP90siRNA treatment mimics GC effects on LCK/FYN activities. These observations support a model for nongenomic GC-induced immunosuppression on the basis of dissolution of membrane-bound GC-receptor multiprotein complexes after GC-receptor ligation.

PMID:
16888650
[PubMed - indexed for MEDLINE]
PMCID:
PMC1618362
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk