Linked Life Data

17645432

Source:http://linkedlifedata.com/resource/pubmed/id/17645432

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2007-9-12
pubmed:abstractText
The Saccharomyces cerevisiae high-affinity copper transporter, Ctr1p, mediates cellular uptake of Cu(I). We report that when copper (50 microm CuSO(4)) is added to the growth medium of copper-starved cells, Ctr1p is rapidly internalized by endocytosis, delivered to the lumen of the lysosome-like vacuole and slowly degraded by vacuolar proteases. Through analysis of the trafficking and degradation of Ctr1p mutants, two lysine residues in the C-terminal cytoplasmic tail of Ctr1p, Lys340 and Lys345, were found to be critical for copper-dependent endocytosis and degradation. In response to copper addition, Ctr1p was found to be ubiquitylated and a mutation in the Rsp5 ubiquitin ligase largely abolished ubiquitylation, endocytosis and degradation. In a strain lacking the Rsp5p accessory factors Bul1p and Bul2p, endocytosis and degradation of Ctr1p-green fluorescent protein were substantially diminished. Surprisingly, a Ctr1p mutant that lacks Lys340 and Lys345 was still ubiquitylated in a copper-dependent manner, indicating that ubiquitylation of Ctr1p on other sites is insufficient to drive copper-dependent endocytosis and degradation. This study demonstrates that copper regulates turnover of Ctr1p by stimulating Rsp5p-dependent endocytosis and degradation of Ctr1p in the vacuole.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1398-9219
pubmed:author
pubmed:issnType
Print
pubmed:volume
8
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1375-84
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Regulation of copper-dependent endocytosis and vacuolar degradation of the yeast copper transporter, Ctr1p, by the Rsp5 ubiquitin ligase.
pubmed:affiliation
Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6058, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural