Linked Life Data

15389538

Source:http://linkedlifedata.com/resource/pubmed/id/15389538

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2004-11-3
pubmed:abstractText
The movement of developing germ cells across the seminiferous epithelium during spermatogenesis involves extensive adherens junction (AJ) restructuring between Sertoli cells, as well as between Sertoli and germ cells. In this report, we show that the intricate interactions between Cdc42 (a Rho family protein of Mr approximately 23 kDa originally identified in membranes of human platelets and placenta, and is the homolog of CDC42Sc, which is known to regulate of bud-site assembly in Saccharomyces cerevisiae) and its effector, IQ motif containing GTPase activating protein (IQGAP1, Mr approximately 189 kDa, it is also an actin-binding protein known to interact with Cdc42 and Rac1 GTPases), regulate Sertoli-germ cell, but not Sertoli-Sertoli cell, AJ dynamics. Using testis lysates for immunoprecipitation (IP), IQGAP1 was shown to associate with E-cadherin, N-cadherin, and beta-catenin (but not beta1-integrin and nectin-2), as well as with actin and vimentin (but not alpha-tubulin). Moreover, IQGAP1 was found to localize to the periphery of both Sertoli and germ cells in the seminiferous epithelium, at sites of cell-cell contacts. Using fluorescent microscopy with dual fluorescent probes, IQGAP1 was found to co-localize, at least in part, with N-cadherin in the seminiferous epithelium consistent with their localization at the basal and apical ES. Using Sertoli-germ cell cocultures, it was demonstrated that AJ assembly associated with a transient induction of Cdc42 and IQGAP1, which was not found when Sertoli cells were cultured alone. Lastly, a shift in the interactions of Cdc42, IQGAP1, beta-catenin, and N-cadherin was detected in Sertoli-germ cell cocultures using an Ca2+-induced AJ disruption model, which was used to examine AJ disassembly and its reassembly. In the presence of Ca2+, IQGAP1 bound preferentially to Cdc42 rather than to beta-catenin. However, when Ca2+ was depleted from cocultures using EGTA, a Ca2+ chelating agent, IQGAP1 lost its affinity for Cdc42 and became tightly associated with beta-catenin, destabilizing cadherin-mediated AJs between Sertoli and germ cells. Yet this shift of protein-protein interaction was not detected in Sertoli cells cultured alone. These results illustrate that the interactions among IQGAP1, Cdc42, and beta-catenin are crucial to the regulation of Sertoli-germ cell, but not Sertoli-Sertoli cell, AJ dynamics in the seminiferous epithelium.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0021-9541
pubmed:author
pubmed:copyrightInfo
2005 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:volume
202
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
49-66
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:15389538-Adherens Junctions, pubmed-meshheading:15389538-Animals, pubmed-meshheading:15389538-Cadherins, pubmed-meshheading:15389538-Calcium Signaling, pubmed-meshheading:15389538-Cell Communication, pubmed-meshheading:15389538-Cell Membrane, pubmed-meshheading:15389538-Cell Movement, pubmed-meshheading:15389538-Cells, Cultured, pubmed-meshheading:15389538-Coculture Techniques, pubmed-meshheading:15389538-Cytoskeletal Proteins, pubmed-meshheading:15389538-Germ Cells, pubmed-meshheading:15389538-Macromolecular Substances, pubmed-meshheading:15389538-Male, pubmed-meshheading:15389538-Microscopy, Electron, Transmission, pubmed-meshheading:15389538-Protein Binding, pubmed-meshheading:15389538-Rats, pubmed-meshheading:15389538-Rats, Sprague-Dawley, pubmed-meshheading:15389538-Seminiferous Epithelium, pubmed-meshheading:15389538-Sertoli Cells, pubmed-meshheading:15389538-Trans-Activators, pubmed-meshheading:15389538-beta Catenin, pubmed-meshheading:15389538-cdc42 GTP-Binding Protein, pubmed-meshheading:15389538-ras GTPase-Activating Proteins
pubmed:year
2005
pubmed:articleTitle
Interactions among IQGAP1, Cdc42, and the cadherin/catenin protein complex regulate Sertoli-germ cell adherens junction dynamics in the testis.
pubmed:affiliation
Population Council, Center for Biomedical Research, New York, New York 10021, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't