Linked Life Data

15240679

Source:http://linkedlifedata.com/resource/pubmed/id/15240679

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2004-7-8
pubmed:abstractText
Transient production of reactive oxygen species (ROS) plays an important role in optimizing transcriptional and proliferative responses to TCR signaling in T lymphocytes. Conversely, chronic oxidative stress leads to decreased proliferative responses and enhanced transcription of inflammatory gene products, and is thought to underlie the altered pathogenic behavior of T lymphocytes in some human diseases, such as rheumatoid arthritis (RA). Although the signaling mechanisms regulating ROS production in T lymphocytes has not been identified, activation of the small GTPase Ras has been shown to couple agonist stimulation to ROS production in other cell types. We find that Ras signaling via Ral stimulates ROS production in human T lymphocytes, and is required for TCR and phorbol ester-induced ROS production. The related small GTPase Rap1 suppresses agonist, Ras and Ral-dependent ROS production through a PI3K-dependent pathway, identifying a novel mechanism by which Rap1 can distally antagonize Ras signaling pathways. In synovial fluid T lymphocytes from RA patients we observed a high rate of endogenous ROS production, correlating with constitutive Ras activation and inhibition of Rap1 activation. Introduction of dominant-negative Ras into synovial fluid T cells restored redox balance, providing evidence that deregulated Ras and Rap1 signaling underlies oxidative stress and consequent altered T cell function observed in RA.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
173
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
920-31
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Rap1 signaling is required for suppression of Ras-generated reactive oxygen species and protection against oxidative stress in T lymphocytes.
pubmed:affiliation
Division of Clinical Immunology and Rheumatology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't