title: Differential mRNA translation contributes to gene regulation under non-stress and dehydration stress conditions in Arabidopsis thaliana.
abstract: Translational regulation was evaluated for over 2000 genes by measurement of the proportion of individual mRNA species in polysomal (PS) complexes in leaves of non-stressed and moderately dehydration-stressed Arabidopsis. The amount of each mRNA in polysomes ranged from 23 to 97% in non-stressed leaves and was significantly reduced for a large portion of the genes (71%) in response to dehydration. The effect of dehydration on translational status varied extensively between mRNA species. Sixty per cent of the dehydration-inducible mRNAs with twofold or greater increase in abundance maintained PS levels in response to water-deficit stress, while 40% showed impaired ribosome loading (RL). PS association declined significantly for 92% of the mRNAs that displayed a strong decrease in abundance, indicating a relationship between translation and decreased gene transcription and/or mRNA stability. Interestingly, many mRNAs that encode proteins of similar biological function displayed coordinate translational regulation. Thus, the abundance of PS mRNA may provide a more accurate estimate of gene expression than total cellular mRNA because of extensive differential translational regulation.
authors.affiliation: Department of Botany and Plant Sciences, Center for Plant Cell Biology, University of California, Riverside, CA 92521-0124, USA.
authors.forename: Riki
authors.initials: R
authors.lastname: Kawaguchi
authors.forename: Thomas
authors.initials: T
authors.lastname: Girke
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Bray
authors.forename: Julia
authors.initials: J
authors.lastname: Bailey-Serres
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000502:physiology; D001483:Base Sequence; D017931:DNA Primers; D018506:Gene Expression Regulation, Plant / Q000235:genetics*; D018745:Genome, Plant; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D016133:Polymerase Chain Reaction / Q000379:methods; D011132:Polyribosomes / Q000235:genetics / Q000378:metabolism; D014176:Protein Biosynthesis / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*; D018749:RNA, Plant / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D014867:Water / Q000378:metabolism
chemical_list: D017931:DNA Primers; D012333:RNA, Messenger; D018749:RNA, Plant; D014867:Water