Prothymosin alpha-receptor associates with lipid rafts in PHA-stimulated lymphocytes.
Lipid rafts are specialized plasma membrane microdomains in which glycosphingolipids and cholesterol are major structural components. Their relative insolubility to nonionic detergents is the most widely used method to purify these structures. Several signalling proteins are associated with these microdomains in T lymphocytes, including receptors for growth factors and cytokines. ProTalpha is a highly conserved and widely distributed protein whose physiological functions remain elusive. In previous works we identified, by means of affinity cross-linking, affinity chromatography and fluorescence microscopy, a set of binding proteins for ProTalpha in human lymphoblasts. Now, this work goes deeply in that ProTalpha receptor description revealing, by different experimental approaches, its presence in lipid rafts. Moreover, our results fit a model in which a tyrosine phosphorylation signalling cascade confined to rafts is initiated upon ProTalpha receptor recognition, which represents an important and promising finding in the research for elucidating the molecular mechanisms underlying the immunomodulatory functions of ProTalpha.
Salgado
Francisco J
FJ
Department of Biochemistry and Molecular Biology, University of Santiago de Compostela, Campus Sur s/n, 15782 Santiago de Compostela, A Coruña, Spain.
Piñeiro
Alicia
A
Canda-Sánchez
Ana
A
Lojo
Juan
J
Nogueira
Montserrat
M
D015703:Antigens, CD; D001665:Binding Sites; D018957:CD59 Antigens; D002352:Carrier Proteins / Q000032:analysis; D002846:Chromatography, Affinity; D003432:Cross-Linking Reagents / Q000494:pharmacology; D006801:Humans; D008214:Lymphocytes / Q000737:chemistry* / Q000187:drug effects; D021962:Membrane Microdomains / Q000737:chemistry* / Q000378:metabolism; D010766:Phosphorylation; D010835:Phytohemagglutinins / Q000494:pharmacology; D011498:Protein Precursors / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D011971:Receptors, Immunologic / Q000032:analysis* / Q000378:metabolism; D011990:Receptors, Transferrin; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000378:metabolism; D013947:Thymosin / Q000031:analogs & derivatives* / Q000276:immunology / Q000378:metabolism / Q000502:physiology; D014443:Tyrosine / Q000378:metabolism
D015703:Antigens, CD; D018957:CD59 Antigens; C068126:CD71 antigen; D002352:Carrier Proteins; D003432:Cross-Linking Reagents; D010835:Phytohemagglutinins; D011498:Protein Precursors; D011971:Receptors, Immunologic; D011990:Receptors, Transferrin; C040782:prothymosin alpha; C086486:prothymosin alpha receptor; D014443:Tyrosine; D013947:Thymosin