Mitochondrial complex II of plants

subunit composition, assembly, and function in respiration and signaling

authored by: Shaobai Huang, Hans Peter Braun, Ryan M.R. Gawryluk, A. Harvey Millar
Abstract: Complex II [succinate dehydrogenase (succinate-ubiquinone oxidoreductase); EC 1.3.5.1; SDH] is the only enzyme shared by both the electron transport chain and the tricarboxylic acid (TCA) cycle in mitochondria. Complex II in plants is considered unusual because of its accessory subunits (SDH5–SDH8), in addition to the catalytic subunits of SDH found in all eukaryotes (SDH1–SDH4). Here, we review compositional and phylogenetic analysis and biochemical dissection studies to both clarify the presence and propose a role for these subunits. We also consider the wider functional and phylogenetic evidence for SDH assembly factors and the reports from plants on the control of SDH1 flavination and SDH1–SDH2 interaction. Plant complex II has been shown to influence stomatal opening, the plant defense response and reactive oxygen species-dependent stress responses. Signaling molecules such as salicyclic acid (SA) and nitric oxide (NO) are also reported to interact with the ubiquinone (UQ) binding site of SDH, influencing signaling transduction in plants. Future directions for SDH research in plants and the specific roles of its different subunits and assembly factors are suggested, including the potential for reverse electron transport to explain the succinate-dependent production of reactive oxygen species in plants and new avenues to explore the evolution of plant mitochondrial complex II and its utility.
Organisation(s): Institute of Plant Genetics
External Organisation(s): University of Western Australia
University of Victoria BC
Type: Review article
Journal: Plant Journal
Volume: 98
Pages: 405-417
No. of pages: 13
ISSN: 0960-7412
Publication date: 29.04.2019
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Genetics, Plant Science, Cell Biology
Electronic version(s): https://rss.onlinelibrary.wiley.com/doi/am-pdf/10.1111/tpj.14227 (Access: Open)
https://doi.org/10.1111/tpj.14227 (Access: Open)