RRC ID 31361
Author Aoyama S, Huarancca Reyes T, Guglielminetti L, Lu Y, Morita Y, Sato T, Yamaguchi J.
Title Ubiquitin ligase ATL31 functions in leaf senescence in response to the balance between atmospheric CO2 and nitrogen availability in Arabidopsis.
Journal Plant Cell Physiol
Abstract Carbon (C) and nitrogen (N) are essential elements for metabolism, and their availability, called the C/N balance, must be tightly coordinated for optimal growth in plants. Previously, we have identified the ubiquitin ligase CNI1/ATL31 as a novel C/N regulator by screening plants grown on C/N stress medium containing excess sugar and limited N. To elucidate further the effect of C/N balance on plant growth and to determine the physiological function of ATL31, we performed C/N response analysis using an atmospheric CO2 manipulation system. Under conditions of elevated CO2 and sufficient N, plant biomass and total sugar and starch dramatically increased. In contrast, elevated CO2 with limited N did not increase plant biomass but promoted leaf chlorosis, with anthocyanin accumulation and increased senescence-associated gene expression. Similar results were obtained with plants grown in medium containing excess sugar and limited N, suggesting that disruption of the C/N balance affects senescence progression. In ATL31-overexpressing plants, promotion of senescence under disrupted CO2/N conditions was repressed, whereas in the loss-of-function mutant it was enhanced. The ATL31 gene was transcriptionally up-regulated under N deficiency and in senescent leaves, and ATL31 expression was highly correlated with WRKY53 expression, a key regulator of senescence. Furthermore, transient protoplast analysis implicated the direct activation of ATL31 expression by WRKY53, which was in accordance with the results of WRKY53 overexpression experiments. Together, these results demonstrate the importance of C/N balance in leaf senescence and the involvement of ubiquitin ligase ATL31 in the process of senescence in Arabidopsis.
Volume 55(2)
Pages 293-305
Published 2014-2-1
DOI 10.1093/pcp/pcu002
PII pcu002
PMID 24399238
PMC PMC3913444
MeSH Anthocyanins / metabolism Arabidopsis / drug effects Arabidopsis / enzymology* Arabidopsis / genetics Arabidopsis / physiology Arabidopsis Proteins / genetics Arabidopsis Proteins / metabolism* Biomass Carbon Dioxide / metabolism* Chlorophyll / metabolism DNA-Binding Proteins / genetics DNA-Binding Proteins / metabolism* Down-Regulation Gene Expression Regulation, Plant* Gene Knockout Techniques Genes, Reporter Mutation Nitrogen / metabolism* Phenotype Photosynthesis Plant Leaves Plants, Genetically Modified Starch / metabolism Time Factors Ubiquitin / metabolism Ubiquitin-Protein Ligases / genetics Ubiquitin-Protein Ligases / metabolism* Up-Regulation
IF 4.062
Times Cited 37
Arabidopsis / Cultured plant cells, genes rpc00008