Involvement of Arabidopsis Hexokinase1 in Cell Death Mediated by Myo -Inositol Accumulation
Type
ArticleAuthors
Bruggeman, QuentinPrunier, Florence
Mazubert, Christelle
De Bont, Linda
Garmier, Marie
Lugan, Raphaël
Benhamed, Moussa

Bergounioux, Catherine
Raynaud, Cécile
Delarue, Marianne
KAUST Department
Biological and Environmental Science and Engineering (BESE) DivisionBioscience Program
Center for Desert Agriculture
Chromatin and development Research Group
Plant Science
Plant Science Program
Date
2015-06-05Online Publication Date
2015-06-05Print Publication Date
2015-06Permanent link to this record
http://hdl.handle.net/10754/575652
Metadata
Show full item recordAbstract
Programmed cell death (PCD) is essential for several aspects of plant life, including development and stress responses. We recently identified the mips1 mutant of Arabidopsis thaliana, which is deficient for the enzyme catalyzing the limiting step of myo-inositol (MI) synthesis. One of the most striking features of mips1 is the light-dependent formation of lesions on leaves due to salicylic acid (SA)-dependent PCD. Here, we identified a suppressor of PCD by screening for mutations that abolish the mips1 cell death phenotype. Our screen identified the hxk1 mutant, mutated in the gene encoding the hexokinase1 (HXK1) enzyme that catalyzes sugar phosphorylation and acts as a genuine glucose sensor. We show that HXK1 is required for lesion formation in mips1 due to alterations in MI content, via SA-dependant signaling. Using two catalytically inactive HXK1 mutants, we also show that hexokinase catalytic activity is necessary for the establishment of lesions in mips1. Gas chromatography-mass spectrometry analyses revealed a restoration of the MI content in mips1 hxk1 that it is due to the activity of the MIPS2 isoform, while MIPS3 is not involved. Our work defines a pathway of HXK1-mediated cell death in plants and demonstrates that two MIPS enzymes act cooperatively under a particular metabolic status, highlighting a novel checkpoint of MI homeostasis in plants. © 2015 American Society of Plant Biologists. All rights reserved.Citation
Bruggeman, Q., Prunier, F., Mazubert, C., de Bont, L., Garmier, M., Lugan, R., … Delarue, M. (2015). Involvement of Arabidopsis Hexokinase1 in Cell Death Mediated by Myo-Inositol Accumulation. The Plant Cell, 27(6), 1801–1814. doi:10.1105/tpc.15.00068Journal
The Plant CellPubMed ID
26048869ae974a485f413a2113503eed53cd6c53
10.1105/tpc.15.00068