Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
24
pubmed:dateCreated
2005-6-13
pubmed:abstractText
The role of actin in endocytosis of G protein-coupled receptors is poorly defined. In the present study, we demonstrate that agents that depolymerize (latrunculin B and cytochalasin D) or stabilize (jasplakinolide) the actin cytoskeleton blocked agonist-induced endocytosis of the beta isoform of the thromboxane A(2) receptor (TPbeta) in HEK293 cells. This suggests that endocytosis of TPbeta requires active remodeling of the actin cytoskeleton. On the other hand, disruption of microtubules with colchicine did not affect endocytosis of the receptor. Expression of wild-type and mutant forms of the small GTPases RhoA and Cdc42 potently inhibited endocytosis of TPbeta, further indicating a role for the dynamic regulation of the actin cytoskeleton in this pathway. Agonist treatment of TPbeta in HEK293 cells resulted in the formation of actin stress fibers through Galpha(q/11) signaling. Because we previously showed that endocytosis of TPbeta is dependent on arrestins, we decided to explore the relation between arrestin-2 and -3 and actin in endocytosis of this receptor. Interestingly, we show that the inhibition of TPbeta endocytosis by the actin toxins in HEK293 cells was overcome by the overexpression of arrestin-3, but not of arrestin-2. These results indicate that the actin cytoskeleton is not essential in arrestin-3-mediated endocytosis of TPbeta. However, arrestin-3 could not promote endocytosis of the TPbetaY339A and TPbetaI343A carboxyl-terminal mutants when the actin cytoskeleton was disrupted. Our data provide new evidence that the actin cytoskeleton plays an essential role in TPbeta endocytosis. Furthermore, our work suggests the existence of actin-dependent and -independent arrestin-mediated pathways of endocytosis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Actins, http://linkedlifedata.com/resource/pubmed/chemical/Antineoplastic Agents, http://linkedlifedata.com/resource/pubmed/chemical/Arrestins, http://linkedlifedata.com/resource/pubmed/chemical/Bicyclo Compounds, Heterocyclic, http://linkedlifedata.com/resource/pubmed/chemical/Clathrin, http://linkedlifedata.com/resource/pubmed/chemical/Colchicine, http://linkedlifedata.com/resource/pubmed/chemical/Cytochalasin D, http://linkedlifedata.com/resource/pubmed/chemical/Depsipeptides, http://linkedlifedata.com/resource/pubmed/chemical/GTP-Binding Protein alpha..., http://linkedlifedata.com/resource/pubmed/chemical/Marine Toxins, http://linkedlifedata.com/resource/pubmed/chemical/Nucleic Acid Synthesis Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Phosphoproteins, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, G-Protein-Coupled, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Thromboxane A2..., http://linkedlifedata.com/resource/pubmed/chemical/Thiazoles, http://linkedlifedata.com/resource/pubmed/chemical/Thiazolidines, http://linkedlifedata.com/resource/pubmed/chemical/arrestin3, http://linkedlifedata.com/resource/pubmed/chemical/cdc42 GTP-Binding Protein, http://linkedlifedata.com/resource/pubmed/chemical/jasplakinolide, http://linkedlifedata.com/resource/pubmed/chemical/latrunculin B, http://linkedlifedata.com/resource/pubmed/chemical/rhoA GTP-Binding Protein
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
280
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
23215-24
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:15845539-Actins, pubmed-meshheading:15845539-Antineoplastic Agents, pubmed-meshheading:15845539-Arrestins, pubmed-meshheading:15845539-Bicyclo Compounds, Heterocyclic, pubmed-meshheading:15845539-Cell Line, pubmed-meshheading:15845539-Clathrin, pubmed-meshheading:15845539-Cloning, Molecular, pubmed-meshheading:15845539-Colchicine, pubmed-meshheading:15845539-Cytochalasin D, pubmed-meshheading:15845539-Cytoskeleton, pubmed-meshheading:15845539-Depsipeptides, pubmed-meshheading:15845539-Endocytosis, pubmed-meshheading:15845539-Enzyme-Linked Immunosorbent Assay, pubmed-meshheading:15845539-GTP-Binding Protein alpha Subunits, Gq-G11, pubmed-meshheading:15845539-Humans, pubmed-meshheading:15845539-Marine Toxins, pubmed-meshheading:15845539-Microscopy, Fluorescence, pubmed-meshheading:15845539-Nucleic Acid Synthesis Inhibitors, pubmed-meshheading:15845539-Phosphoproteins, pubmed-meshheading:15845539-Plasmids, pubmed-meshheading:15845539-Protein Binding, pubmed-meshheading:15845539-Protein Structure, Tertiary, pubmed-meshheading:15845539-Receptors, G-Protein-Coupled, pubmed-meshheading:15845539-Receptors, Thromboxane A2, Prostaglandin H2, pubmed-meshheading:15845539-Signal Transduction, pubmed-meshheading:15845539-Thiazoles, pubmed-meshheading:15845539-Thiazolidines, pubmed-meshheading:15845539-Time Factors, pubmed-meshheading:15845539-Transfection, pubmed-meshheading:15845539-cdc42 GTP-Binding Protein, pubmed-meshheading:15845539-rhoA GTP-Binding Protein
pubmed:year
2005
pubmed:articleTitle
Involvement of actin in agonist-induced endocytosis of the G protein-coupled receptor for thromboxane A2: overcoming of actin disruption by arrestin-3 but not arrestin-2.
pubmed:affiliation
Service de Rhumatologie, Département de Médecine, Faculté de Médecine and Centre de Recherche Clinique, Université de Sherbrooke, Quebec, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't