Show simple item record

dc.contributor.authorSchandel, Kimberly A.
dc.contributor.authorJenness, Duane D.
dc.date2022-08-11T08:09:33.000
dc.date.accessioned2022-08-23T16:35:35Z
dc.date.available2022-08-23T16:35:35Z
dc.date.issued1994-11-01
dc.date.submitted2009-03-24
dc.identifier.citationMol Cell Biol. 1994 Nov;14(11):7245-55.
dc.identifier.issn0270-7306 (Print)
dc.identifier.pmid7935439
dc.identifier.urihttp://hdl.handle.net/20.500.14038/38594
dc.description.abstractWhen Saccharomyces cerevisiae a cells bind alpha-factor pheromone, the ligand is internalized and its binding sites are lost from the cell surface in a time-, energy-, and temperature-dependent manner. This report presents direct evidence for alpha-factor-induced internalization of cell surface receptors. First, membrane fractionation on Renografin density gradients indicated that the alpha-factor receptors were predominantly found in the plasma membrane peak before alpha-factor treatment and then appeared in membranes of lesser buoyant density after alpha-factor exposure. Second, receptors were susceptible to cleavage by extracellular proteases before alpha-factor treatment and then became resistant to proteolysis after exposure to pheromone, consistent with the transit of receptors from the cell surface to an internal compartment. The median transit time in both assays was approximately 8 min. The ultimate target of the internalized receptors was identified as the vacuole, since the membranes containing internalized receptors cofractionated with vacuolar membranes, since the turnover of receptors was stimulated by alpha-factor exposure, and since receptor degradation was blocked in a pep4 mutant that is deficient for vacuolar proteases. The carboxy-terminal domain of the receptor that is required for ligand internalization was also found to be essential for endocytosis of the receptor. A receptor mutant, ste2-L236H, which is defective for pheromone response but capable of ligand internalization, was found to be proficient for receptor endocytosis. Hence, separate structural features of the receptor appear to specify its signal transduction and internalization activities.
dc.language.isoen_US
dc.relation<a href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&list_uids=7935439&dopt=Abstract">Link to Article in PubMed</a>
dc.subjectBiological Transport, Active
dc.subjectCell Membrane
dc.subjectEndocytosis
dc.subjectEndopeptidases
dc.subjectGenes, Fungal
dc.subjectKinetics
dc.subjectMutation
dc.subjectPeptides
dc.subjectReceptors, Mating Factor
dc.subjectReceptors, Peptide
dc.subjectSaccharomyces cerevisiae
dc.subjectSequence Deletion
dc.subjectSignal Transduction
dc.subject*Transcription Factors
dc.subjectVacuoles
dc.subjectLife Sciences
dc.subjectMedicine and Health Sciences
dc.titleDirect evidence for ligand-induced internalization of the yeast alpha-factor pheromone receptor
dc.typeJournal Article
dc.source.journaltitleMolecular and cellular biology
dc.source.volume14
dc.source.issue11
dc.identifier.legacyfulltexthttps://escholarship.umassmed.edu/cgi/viewcontent.cgi?article=2458&amp;context=oapubs&amp;unstamped=1
dc.identifier.legacycoverpagehttps://escholarship.umassmed.edu/oapubs/1459
dc.identifier.contextkey794956
refterms.dateFOA2022-08-23T16:35:35Z
html.description.abstract<p>When Saccharomyces cerevisiae a cells bind alpha-factor pheromone, the ligand is internalized and its binding sites are lost from the cell surface in a time-, energy-, and temperature-dependent manner. This report presents direct evidence for alpha-factor-induced internalization of cell surface receptors. First, membrane fractionation on Renografin density gradients indicated that the alpha-factor receptors were predominantly found in the plasma membrane peak before alpha-factor treatment and then appeared in membranes of lesser buoyant density after alpha-factor exposure. Second, receptors were susceptible to cleavage by extracellular proteases before alpha-factor treatment and then became resistant to proteolysis after exposure to pheromone, consistent with the transit of receptors from the cell surface to an internal compartment. The median transit time in both assays was approximately 8 min. The ultimate target of the internalized receptors was identified as the vacuole, since the membranes containing internalized receptors cofractionated with vacuolar membranes, since the turnover of receptors was stimulated by alpha-factor exposure, and since receptor degradation was blocked in a pep4 mutant that is deficient for vacuolar proteases. The carboxy-terminal domain of the receptor that is required for ligand internalization was also found to be essential for endocytosis of the receptor. A receptor mutant, ste2-L236H, which is defective for pheromone response but capable of ligand internalization, was found to be proficient for receptor endocytosis. Hence, separate structural features of the receptor appear to specify its signal transduction and internalization activities.</p>
dc.identifier.submissionpathoapubs/1459
dc.contributor.departmentDepartment of Molecular Genetics and Microbiology
dc.source.pages7245-55


Files in this item

Thumbnail
Name:
7935439.pdf
Size:
2.639Mb
Format:
PDF

This item appears in the following Collection(s)

Show simple item record