Photoperiod Affects the Phenotype of Mitochondrial Complex I Mutants

Pierre Pétriacq (1, 2) , Linda de Bont (2) , Lucie Genestout (2) , Jingfang Hao (2) , Constance Laureau (3) , Igor Florez-Sarasa (4) , Touhami Rzigui (3) , Guillaume Queval (2) , Françoise Gilard (5) , Caroline Mauve (5) , Florence Guérard (5) , Marlène Lamothe-Sibold (5) , Jessica Marion (6) , Chantal Fresneau (3) , Spencer Brown (6) , Antoine Danon (7, 2) , Anja Krieger-Liszkay (6) , Richard Berthomé (8) , Miquel Ribas-Carbo (4) , Guillaume Tcherkez (9) , Gabriel Cornic (3) , Bernard Pineau (6) , Bertrand Gakière (6, 5) , Rosine de Paepe (6)

1 University of Sheffield [Sheffield]
2 IPS2 (UMR_9213 / UMR_1403) - Institut des Sciences des Plantes de Paris-Saclay
3 ESE - Ecologie Systématique et Evolution
4 UIB - Universitat de les Illes Balears = Universidad de las Islas Baleares = University of the Balearic Islands
5 IFR87 - Plateforme Métabolisme-Métabolome
6 I2BC - Institut de Biologie Intégrative de la Cellule
7 LCQB - Biologie Computationnelle et Quantitative = Laboratory of Computational and Quantitative Biology
8 LIPM - Laboratoire des interactions plantes micro-organismes
9 ANU - Australian National University

Plant mutants for genes encoding subunits of mitochondrial complex I (CI; NADH:ubiquinone oxidoreductase), the first enzyme of the respiratory chain, display various phenotypes depending on growth conditions. Here, we examined the impact of photoperiod, a major environmental factor controlling plant development, on two Arabidopsis (Arabidopsis thaliana) CI mutants: a new insertion mutant interrupted in both ndufs8.1 and ndufs8.2 genes encoding the NDUFS8 subunit and the previously characterized ndufs4 CI mutant. In the long day (LD) condition, both ndufs8.1 and ndufs8.2 single mutants were indistinguishable from Columbia-0 at phenotypic and biochemical levels, whereas the ndufs8.1 ndufs8.2 double mutant was devoid of detectable holo-CI assembly/activity, showed higher alternative oxidase content/activity, and displayed a growth retardation phenotype similar to that of the ndufs4 mutant. Although growth was more affected in ndufs4 than in ndufs8.1 ndufs8.2 under the short day (SD) condition, both mutants displayed a similar impairment of growth acceleration after transfer to LD compared with the wild type. Untargeted and targeted metabolomics showed that overall metabolism was less responsive to the SD-to-LD transition in mutants than in the wild type. The typical LD acclimation of carbon and nitrogen assimilation as well as redox-related parameters was not observed in ndufs8.1 ndufs8. Similarly, NAD(H) content, which was higher in the SD condition in both mutants than in Columbia-0, did not adjust under LD. We propose that altered redox homeostasis and NAD(H) content/redox state control the phenotype of CI mutants and photoperiod acclimation in Arabidopsis

Domaines: Botanique

Pierre Pétriacq, Linda de Bont, Lucie Genestout, Jingfang Hao, Constance Laureau, et al.. Photoperiod Affects the Phenotype of Mitochondrial Complex I Mutants. Plant Physiology, 2017, 173 (1), pp.434 - 455. ⟨10.1104/pp.16.01484⟩. ⟨hal-03721494⟩