title: Arabidopsis coordinates the diurnal regulation of carbon allocation and growth across a wide range of photoperiods.
abstract: In short photoperiods, plants accumulate starch more rapidly in the light and degrade it more slowly at night, ensuring that their starch reserves last until dawn. To investigate the accompanying changes in the timing of growth, Arabidopsis was grown in a range of photoperiods and analyzed for rosette biomass, photosynthesis, respiration, ribosome abundance, polysome loading, starch, and over 40 metabolites at dawn and dusk. The data set was used to model growth rates in the daytime and night, and to identify metabolites that correlate with growth. Modeled growth rates and polysome loading were high in the daytime and at night in long photoperiods, but decreased at night in short photoperiods. Ribosome abundance was similar in all photoperiods. It is discussed how the amount of starch accumulated in the light period, the length of the night, and maintenance costs interact to constrain growth at night in short photoperiods, and alter the strategy for optimizing ribosome use. Significant correlations were found in the daytime and the night between growth rates and the levels of the sugar-signal trehalose 6-phosphate and the amino acid biosynthesis intermediate shikimate, identifying these metabolites as hubs in a network that coordinates growth with diurnal changes in the carbon supply.
authors.affiliation: Max Planck Institute of Molecular Plant Physiology, Am Muehlenberg 1, 14476 Potsdam-Golm, Germany.
authors.forename: Ronan
authors.initials: R
authors.lastname: Sulpice
authors.forename: Anna
authors.initials: A
authors.lastname: Flis
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Ivakov
authors.forename: Federico
authors.initials: F
authors.lastname: Apelt
authors.forename: Nicole
authors.initials: N
authors.lastname: Krohn
authors.forename: Beatrice
authors.initials: B
authors.lastname: Encke
authors.forename: Christin
authors.initials: C
authors.lastname: Abel
authors.forename: Regina
authors.initials: R
authors.lastname: Feil
authors.forename: John E
authors.initials: JE
authors.lastname: Lunn
authors.forename: Mark
authors.initials: M
authors.lastname: Stitt
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D017360:Arabidopsis / Q000254:growth & development* / Q000378:metabolism* / Q000502:physiology / Q000528:radiation effects; D050260:Carbohydrate Metabolism; D002244:Carbon / Q000378:metabolism*; D019069:Cell Respiration; D002940:Circadian Rhythm; D003624:Darkness; D007700:Kinetics; D017440:Photoperiod; D010788:Photosynthesis; D011132:Polyribosomes / Q000378:metabolism; D013213:Starch / Q000378:metabolism
chemical_list: D000596:Amino Acids; D002244:Carbon; D013213:Starch
keywords: Arabidopsis; diurnal; growth; photoperiod; ribosomes; starch.; trehalose-6-phosphate