Linked Life Data

3308865

Source:http://linkedlifedata.com/resource/pubmed/id/3308865

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
27
pubmed:dateCreated
1987-11-2
pubmed:abstractText
Purified yeast copper-metallothionein lacks 8 amino-terminal residues that are predicted from the DNA sequence of its gene. The removed sequence is unusual for metallothionein in its high content of hydrophobic and aromatic residues and its similarity to mitochondrial leader sequences. To study the significance of this amino-terminal cleavage, several mutations were introduced into the metallothionein coding gene, CUP1. One mutant, which deletes amino acid residues 2-8, had a minor effect on the ability of the molecule to confer copper resistance to yeast but did not affect CUP1 gene regulation. A second mutation, which changes two amino acids adjacent to the cleavage site, blocked removal of the extension peptide but had no effect on copper detoxification or gene regulation. Immunofluorescence studies showed that both the wild-type and these two mutant proteins are predominantly cytoplasmic with no evidence for mitochondrial localization. The cleavage site mutation allowed isolation and structural characterization of a full length metallothionein polypeptide. The copper content and luminescent properties of this molecule were identical to those of the truncated wild-type protein indicating a homologous cluster structure. Moreover, the amino-terminal peptide was selectively removed by various endopeptidases and an exopeptidase suggesting that it does not participate in the tertiary fold. These results argue that the amino-terminal peptide is not required for either the structural integrity or biological function of yeast metallothionein.
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
25
pubmed:volume
262
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
12912-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Structural and functional studies of the amino terminus of yeast metallothionein.
pubmed:affiliation
Laboratory of Biochemistry, National Cancer Institute, Bethesda, Maryland 20892.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.