Linked Life Data

18392778

Source:http://linkedlifedata.com/resource/pubmed/id/18392778

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2008-6-3
pubmed:abstractText
MicroRNAs (miRNAs) are approximately 21-nt RNAs that reduce target accumulation through mRNA cleavage or translational repression. Arabidopsis miR398 regulates mRNAs encoding two copper superoxide dismutase (CSD) enzymes and a cytochrome c oxidase subunit. miR398 itself is down-regulated in response to copper and stress. Here we show that miR398 is positively regulated by sucrose, resulting in decreased CSD1 and CSD2 mRNA and protein accumulation. This sucrose regulation is maintained both in the presence and absence of physiologically relevant levels of supplemental copper. Additionally, we show that plants expressing CSD1 and CSD2 mRNAs with altered miR398 complementarity sites display increased mRNA accumulation, whereas CSD1 and CSD2 protein accumulation remain sensitive to miR398 levels, suggesting that miR398 can act as a translational repressor when target site complementarity is reduced. These results reveal a novel miR398 regulatory mechanism and demonstrate that plant miRNA targets can resist miRNA regulation at the mRNA level while maintaining sensitivity at the level of protein accumulation. Our results suggest that even in plants, where miRNAs are thought to act primarily through target mRNA cleavage, monitoring target protein levels along with target mRNA levels is necessary to fully assess the consequences of disrupted miRNA-mRNA pairing. Moreover, the limited complementarity required to maintain robust miR398-directed repression of target protein accumulation suggests that similarly regulated endogenous plant miRNA targets may have eluded detection.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0167-4412
pubmed:author
pubmed:issnType
Print
pubmed:volume
67
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
403-17
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Sucrose induction of Arabidopsis miR398 represses two Cu/Zn superoxide dismutases.
pubmed:affiliation
Department of Biochemistry and Cell Biology, Rice University, Houston, TX 77005, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural