Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1993-1-19
pubmed:abstractText
The PsMTA gene from pea (Pisum sativum) shares similarity with metallothionein (MT) genes and related sequences have also been isolated from a number of other higher-plant species. The proteins encoded by these genes have not yet been purified from plants and their functions remain unclear although, by analogy to MT, roles in the metabolism and detoxification of metal ions have been proposed. By contrast, correlation between transcript abundance and Fe availability has led to an alternative proposal that these genes are involved in mechanisms of Fe efficiency. Phenotypic effects of constitutive PsMTA expression were examined in Escherichia coli and Arabidopsis thaliana. Copper accumulation by E. coli cells expressing recombinant PsMTA protein was approximately 8-fold greater than in control cells. No significant effects on the accumulation of Zn or Cd were detected. In segregating A. thaliana progeny, derived from a transgenic F1 parent containing the PsMTA gene under the control of a CaMV 35S promoter, 75% of individuals accumulated more Cu (several-fold in some plants) than untransformed, control plants. These data suggest that PsMTA protein binds Cu in planta and that uncoupled (constitutive) expression of the PsMTA gene causes enhanced Cu accumulation. Roots of P. sativum plants grown under conditions of low Fe availability showed elevated activity of root surface Fe(III) reductase and accumulated more Cu than roots of plants grown in an Fe-supplemented solution. Changes in the expression of MT-like genes, coincident with changes in Fe availability, are consistent with a role in Cu homoeostasis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0167-4412
pubmed:author
pubmed:issnType
Print
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1019-28
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:1463837-Arabidopsis, pubmed-meshheading:1463837-Base Sequence, pubmed-meshheading:1463837-Blotting, Southern, pubmed-meshheading:1463837-Cadmium, pubmed-meshheading:1463837-Cloning, Molecular, pubmed-meshheading:1463837-Copper, pubmed-meshheading:1463837-Escherichia coli, pubmed-meshheading:1463837-Fabaceae, pubmed-meshheading:1463837-Gene Expression, pubmed-meshheading:1463837-Genes, Plant, pubmed-meshheading:1463837-Iron, pubmed-meshheading:1463837-Metallothionein, pubmed-meshheading:1463837-Metals, pubmed-meshheading:1463837-Molecular Sequence Data, pubmed-meshheading:1463837-Oligodeoxyribonucleotides, pubmed-meshheading:1463837-Plants, Medicinal, pubmed-meshheading:1463837-Polymerase Chain Reaction, pubmed-meshheading:1463837-RNA, Messenger, pubmed-meshheading:1463837-Zinc
pubmed:year
1992
pubmed:articleTitle
Expression of the pea metallothionein-like gene PsMTA in Escherichia coli and Arabidopsis thaliana and analysis of trace metal ion accumulation: implications for PsMTA function.
pubmed:affiliation
Department of Biological Sciences, University of Durham, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't