AUTHOR=Farhat Nèjia , Hichri Sarra , Hildebrandt Tatjana Manuela , Debez Ahmed , Braun Hans-Peter 

TITLE=Composition and Stability of the Oxidative Phosphorylation System in the Halophile Plant Cakile maritima

JOURNAL=Frontiers in Plant Science

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2019.01010

DOI=10.3389/fpls.2019.01010

ISSN=1664-462X

ABSTRACT=<p>Mitochondria play a central role in the energy metabolism of plants. At the same time, they provide energy for plant stress responses. We here report a first view on the mitochondrial Oxidative Phosphorylation (OXPHOS) system of the halophile (salt tolerant) plant <italic>Cakile maritima</italic>. Mitochondria were purified from suspension cultures of <italic>C. maritima</italic> and for comparison of <italic>Arabidopsis thaliana</italic>, a closely related glycophyte (salt sensitive) plant. Mitochondria were treated with digitonin and solubilized protein complexes were analyzed by 2D Blue native/SDS polyacrylamide gel electrophoresis. The OXPHOS systems of the two compared plants exhibit some distinct differences. <italic>C. maritima</italic> mitochondria include a very abundant respiratory supercomplex composed of monomeric complex I and dimeric complex III. At the same time the complexes II and IV are of reduced abundance. The stability of the OXPHOS complexes was investigated by combined salt and temperature treatments of isolated mitochondria. ATP synthase (complex V) is of increased stability in <italic>C. maritima</italic>. Also, the I + III<sub>2</sub> supercomplex is present in high abundance during stress treatments. These results give insights into the mitochondrial contribution to the plant salt stress response.</p>