title: An Arabidopsis stomatin-like protein affects mitochondrial respiratory supercomplex organization.
abstract: Stomatins belong to the band-7 protein family, a diverse group of conserved eukaryotic and prokaryotic membrane proteins involved in the formation of large protein complexes as protein-lipid scaffolds. The Arabidopsis (Arabidopsis thaliana) genome contains two paralogous genes encoding stomatin-like proteins (SLPs; AtSLP1 and AtSLP2) that are phylogenetically related to human SLP2, a protein involved in mitochondrial fusion and protein complex formation in the mitochondrial inner membrane. We used reverse genetics in combination with biochemical methods to investigate the function of AtSLPs. We demonstrate that both SLPs localize to mitochondrial membranes. SLP1 migrates as a large (approximately 3 MDa) complex in blue-native gel electrophoresis. Remarkably, slp1 knockout mutants have reduced protein and activity levels of complex I and supercomplexes, indicating that SLP affects the assembly and/or stability of these complexes. These findings point to a role for SLP1 in the organization of respiratory supercomplexes in Arabidopsis.
authors.affiliation: Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom.
authors.forename: Bernadette
authors.initials: B
authors.lastname: Gehl
authors.forename: Chun Pong
authors.initials: CP
authors.lastname: Lee
authors.forename: Pedro
authors.initials: P
authors.lastname: Bota
authors.forename: Michael R
authors.initials: MR
authors.lastname: Blatt
authors.forename: Lee J
authors.initials: LJ
authors.lastname: Sweetlove
mesh_terms: D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D019069:Cell Respiration; D004269:DNA, Bacterial / Q000378:metabolism; D004579:Electron Transport; D056626:Inflorescence / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism*; D051336:Mitochondrial Membranes / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000378:metabolism*; D046912:Multiprotein Complexes / Q000378:metabolism*; D016254:Mutagenesis, Insertional / Q000235:genetics; D009154:Mutation / Q000235:genetics; D021381:Protein Transport; D036226:Seedlings / Q000254:growth & development / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D004269:DNA, Bacterial; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D046912:Multiprotein Complexes; C000592613:SLP1 protein, Arabidopsis; C000592614:SLP2 protein, Arabidopsis; C036483:T-DNA