title: Ribosome and transcript copy numbers, polysome occupancy and enzyme dynamics in Arabidopsis.
abstract: Plants are exposed to continual changes in the environment. The daily alternation between light and darkness results in massive recurring changes in the carbon budget, and leads to widespread changes in transcript levels. These diurnal changes are superimposed on slower changes in the environment. Quantitative molecular information about the numbers of ribosomes, of transcripts for 35 enzymes in central metabolism and their loading into polysomes is used to estimate translation rates in Arabidopsis rosettes, and explore the consequences for important sub-processes in plant growth. Translation rates for individual enzyme are compared with their abundance in the rosette to predict which enzymes are subject to rapid turnover every day, and which are synthesized at rates that would allow only slow adjustments to sustained changes of the environment, or resemble those needed to support the observed rate of growth. Global translation rates are used to estimate the energy costs of protein synthesis and relate them to the plant carbon budget, in particular the rates of starch degradation and respiration at night.
authors.affiliation: Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, Potsdam-Golm, Germany.
authors.forename: Maria
authors.initials: M
authors.lastname: Piques
authors.forename: Waltraud X
authors.initials: WX
authors.lastname: Schulze
authors.forename: Melanie
authors.initials: M
authors.lastname: Höhne
authors.forename: Björn
authors.initials: B
authors.lastname: Usadel
authors.forename: Yves
authors.initials: Y
authors.lastname: Gibon
authors.forename: Johann
authors.initials: J
authors.lastname: Rohwer
authors.forename: Mark
authors.initials: M
authors.lastname: Stitt
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000096:biosynthesis / Q000235:genetics; D002940:Circadian Rhythm / Q000235:genetics; D003062:Codon / Q000235:genetics; D003624:Darkness; D018628:Gene Dosage / Q000235:genetics*; D018506:Gene Expression Regulation, Plant; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics; D011132:Polyribosomes / Q000378:metabolism*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D003062:Codon; D012333:RNA, Messenger