TY - JOUR

T1 - The Levels of Sulfur-containing Metabolites in Brassica napus are Not Influenced by the Circadian Clock but Diurnally

AU - Hornbacher, Johann

AU - Rumlow, Annekathrin

AU - Pallmann, Philip

AU - Turcios, Ariel E.

AU - Riemenschneider, Anja

AU - Papenbrock, Jutta

N1 - Funding information: We acknowledge the Deutsche Saatveredelung AG, Lippstadt, Germany, for providing us with seeds of the Brassica napus cultivar. We would like to thank Julia Volker and Pamela von Trzebiatowski, Hannover, for their excellent technical assistance and the gardener Yvonne Leye for taking care of the plants. We gratefully acknowledge Dr. Elke Bloem, Julius-Kühn-Institut, Germany, who analyzed the samples for their sulfate content.

PY - 2019/10

Y1 - 2019/10

N2 - Adapting biological processes to an endogenous rhythm enables plants to cope with the daily changes in light and temperature in a more predictable way enhancing growth and fitness. A number of biological processes such as metabolic pathways as well as the immunity in plants are under diurnal or circadian control. In this study a possible circadian regulation of key enzymes in the sulfur assimilation and the corresponding metabolites was investigated in the agriculturally important crop plant oilseed rape (Brassica napus). Leaves of a commercially available cultivar were harvested in the course of a day under diurnal and under free-running conditions with constant light. Analyses in this study were focused on sulfur-containing metabolites and expression analysis of enzymes involved in sulfur assimilation. Expression analysis showed that the transcript levels of the sulfate transporters Sultr3;1 and Sultr4;2 as well as APR2 and APR3 oscillated diurnally. Results revealed a periodic rhythm of sulfur-containing metabolites such as glutathione, sulfate and certain glucosinolates in the course of a day which were only partly maintained under constant light. Therefore, we conclude that a diurnal rhythm and not the circadian clock regulates sulfur metabolism in plants.

AB - Adapting biological processes to an endogenous rhythm enables plants to cope with the daily changes in light and temperature in a more predictable way enhancing growth and fitness. A number of biological processes such as metabolic pathways as well as the immunity in plants are under diurnal or circadian control. In this study a possible circadian regulation of key enzymes in the sulfur assimilation and the corresponding metabolites was investigated in the agriculturally important crop plant oilseed rape (Brassica napus). Leaves of a commercially available cultivar were harvested in the course of a day under diurnal and under free-running conditions with constant light. Analyses in this study were focused on sulfur-containing metabolites and expression analysis of enzymes involved in sulfur assimilation. Expression analysis showed that the transcript levels of the sulfate transporters Sultr3;1 and Sultr4;2 as well as APR2 and APR3 oscillated diurnally. Results revealed a periodic rhythm of sulfur-containing metabolites such as glutathione, sulfate and certain glucosinolates in the course of a day which were only partly maintained under constant light. Therefore, we conclude that a diurnal rhythm and not the circadian clock regulates sulfur metabolism in plants.

KW - Brassica napus

KW - Circadian clock

KW - Diurnal rhythm

KW - Expression analysis

KW - Sulfur-containing metabolites

UR - http://www.scopus.com/inward/record.url?scp=85073252554&partnerID=8YFLogxK

U2 - 10.1007/s12374-019-0143-x

DO - 10.1007/s12374-019-0143-x

M3 - Article

AN - SCOPUS:85073252554

VL - 62

SP - 359

EP - 373

JO - Journal of plant biology

JF - Journal of plant biology

SN - 1226-9239

IS - 5

ER -