The mitochondrial LYR protein SDHAF1 is required for succinate dehydrogenase activity in Arabidopsis
Ying Li1, Katharina Belt1, Saad F Alqahtani1,2
1ARC Centre of Excellence in Plant Energy Biology, School of Molecular Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia.
Abstract:
Succinate dehydrogenase (SDH, complex II), which plays an essential role in mitochondrial respiration and tricarboxylic acid metabolism, requires the assembly of eight nuclear-encoded subunits and the insertion of various cofactors. Here, we report on the characterization of an Arabidopsis thaliana leucine-tyrosine-arginine (LYR) protein family member SDHAF1, (At2g39725) is a factor required for SDH activity. SDHAF1 is located in mitochondria and can fully complement the yeast SDHAF1 deletion strain. Knockdown of SDHAF1 using RNA interference resulted in a decrease in seedling hypocotyl elongation and reduced SDH activity. Proteomic analyses revealed a decreased abundance of various SDH subunits and assembly factors. Protein interaction assays revealed that SDHAF1 can interact exclusively with the Fe-S cluster-containing subunit SDH2 and HSCB, a cochaperone involved in Fe-S cluster complex recruitment. Therefore, we propose that in Arabidopsis, SDHAF1 plays a role in the biogenesis of SDH2 to form the functional complex II, which is essential for mitochondrial respiration and metabolism.
Related Concept Videos
Electron Transport Chain: Complex I and II
ROS generation is regulated and maintained at moderate levels necessary...
ATP Synthase: Mechanism
The Citric Acid Cycle
The Inner Mitochondrial Membrane
The ADP/ATP Carrier Protein
Translocation of Proteins into the Mitochondria
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...


