Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2010-12-28
pubmed:abstractText
Leptin is produced in placenta where it has been found to be an important autocrine signal for trophoblastic growth during pregnancy, promoting antiapoptotic and trophic effects. Leptin receptor is present in trophoblastic cells and leptin may fully activate signaling. We have previously implicated the RNA-binding protein Sam68 in leptin signal transduction in immune cells. In the present work, we have studied the possible role of Sam68 in leptin receptor signaling in trophoblastic cells (JEG-3 cells). Leptin dose-dependently stimulated Sam68 phosphorylation in JEG-3 cells, as assessed by immunoprecipitation and immunoblot with anti-phosphotyrosine antibodies. As previously observed in other systems, tyrosine phosphorylation of Sam68 in response to leptin inhibits its RNA binding capacity. Besides, leptin stimulation dose-dependently increases Sam68 expression in JEG-3 cells, as assessed by quantitative PCR. Consistently, the amount of Sam68 protein is increased after 24h of leptin stimulation of trophoblastic cells. In order to study the possible role of Sam68 on leptin receptor synthesis, we employed antisense strategy to knockdown the expression of Sam68. We have found that a decrease in Sam68 expression leads to a decrease in leptin receptor amount in JEG-3 cells, as assessed both by quantitative PCR and immunoblot. These results strongly suggest the participation of Sam68 in leptin receptor signaling in human trophoblastic cells, and therefore, Sam68 may mediate some of the leptin effects in placenta.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1872-8057
pubmed:author
pubmed:copyrightInfo
Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.
pubmed:issnType
Electronic
pubmed:day
30
pubmed:volume
332
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
221-7
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Leptin receptor activation increases Sam68 tyrosine phosphorylation and expression in human trophoblastic cells.
pubmed:affiliation
Department of Clinical Biochemistry, Virgen Macarena University Hospital, University of Seville, Av Dr Fedriani 3, Seville 41071, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't