Linked Life Data

20374530

Source:http://linkedlifedata.com/resource/pubmed/id/20374530

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2010-7-19
pubmed:abstractText
A genetic screen in Arabidopsis was developed to explore the regulation of chloroplast protein import in vivo using two independent reporters representing housekeeping and photosynthetic pre-proteins. We first used 5-enolpyruvylshikimate 3-phosphate synthase (EPSP synthase*), a key enzyme in the shikimic acid pathway, with a mutation that confers tolerance to the herbicide glyphosate. Because the EPSP synthase* pre-protein must be imported for its function, the loss of glyphosate tolerance provided an initial indication of an import deficiency. Second, the fate of GFP fused to a ferredoxin transit peptide (FD5-GFP) was determined. A class of altered chloroplast import (aci) mutants showed both glyphosate sensitivity and FD5-GFP mislocalized to nuclei. aci2-1 was selected for further study. Yellow fluorescent protein (YFP) fused to the transit peptide of EPSP synthase* or the small subunit of Rubisco was not imported into chloroplasts, but also localized to nuclei during protoplast transient expression. Isolated aci2-1 chloroplasts showed a 50% reduction in pre-protein import efficiency in an in vitro assay. Mutants did not grow photoautotrophically on media without sucrose and were small and dark green in soil. aci2-1 and two alleles code for Moco-sulfurase, which activates the aldehyde oxidases required for the biosynthesis of the plant hormones abscisic acid (ABA) and indole-acetic acid (IAA) and controls purine nucleotide (ATP and GTP) turnover and nitrogen recycling via xanthine dehydrogenase. These enzyme activities were not detected in aci2-1. ABA, IAA and/or purine turnover may play previously unrecognized roles in the regulation of chloroplast protein import in response to developmental, metabolic and environmental cues.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1365-313X
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
63
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
44-59
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
A forward genetic screen to explore chloroplast protein import in vivo identifies Moco sulfurase, pivotal for ABA and IAA biosynthesis and purine turnover.
pubmed:affiliation
Department of Molecular Genetics and Cell Biology, The University of Chicago, 920 East 58th Street, Chicago, IL 60637, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.