Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
36
pubmed:dateCreated
1999-10-7
pubmed:abstractText
Ornithine decarboxylase (ODC) declines in cells that accumulate an excess of polyamines, the downstream products of the enzyme. Superfluous production of polyamines is thus prevented. In animal cells, polyamines reduce ODC activity by accelerating its degradation. Similar down-regulation of ODC activity has been observed in the budding yeast Saccharomyces cerevisiae, but induced degradation has not been documented. Here we show using pulse-chase analysis that the loss of enzyme activity is the result of increased degradation of ODC. Polyamines reduce the half-life of the newly synthesized protein from 3 h to approximately 10 min. Degradation of bulk ODC pools is also accelerated by polyamines, but the absolute rate of turnover is slower, with a half-life of 5 h in untreated and 1 h in treated cells. Newly synthesized ODC polypeptide thus undergoes a process of maturation that renders it relatively resistant to both basal and polyamine-induced degradation. Proteasome mutants have a blunted or absent regulatory response, implicating both the core protease and the regulatory cap of the proteasome in induced degradation of yeast ODC.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
3
pubmed:volume
274
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
25921-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Regulated degradation of yeast ornithine decarboxylase.
pubmed:affiliation
Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California 94143-0414, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.