Formation of cristae and crista junctions in mitochondria depends on antagonism between Fcj1 and Su e/g.
Crista junctions (CJs) are important for mitochondrial organization and function, but the molecular basis of their formation and architecture is obscure. We have identified and characterized a mitochondrial membrane protein in yeast, Fcj1 (formation of CJ protein 1), which is specifically enriched in CJs. Cells lacking Fcj1 lack CJs, exhibit concentric stacks of inner membrane in the mitochondrial matrix, and show increased levels of F(1)F(O)-ATP synthase (F(1)F(O)) supercomplexes. Overexpression of Fcj1 leads to increased CJ formation, branching of cristae, enlargement of CJ diameter, and reduced levels of F(1)F(O) supercomplexes. Impairment of F(1)F(O) oligomer formation by deletion of its subunits e/g (Su e/g) causes CJ diameter enlargement and reduction of cristae tip numbers and promotes cristae branching. Fcj1 and Su e/g genetically interact. We propose a model in which the antagonism between Fcj1 and Su e/g locally modulates the F(1)F(O) oligomeric state, thereby controlling membrane curvature of cristae to generate CJs and cristae tips.
Rabl
Regina
R
Adolf-Butenandt Institute for Physiological Chemistry, Ludwig-Maximilians University, 81377 Munich, Germany.
Soubannier
Vincent
V
Scholz
Roland
R
Vogel
Frank
F
Mendl
Nadine
N
Vasiljev-Neumeyer
Andreja
A
Körner
Christian
C
Jagasia
Ravi
R
Keil
Thomas
T
Baumeister
Wolfgang
W
Cyrklaff
Marek
M
Neupert
Walter
W
Reichert
Andreas S
AS
D004272:DNA, Mitochondrial / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007425:Intracellular Membranes / Q000378:metabolism / Q000648:ultrastructure; D008928:Mitochondria / Q000378:metabolism / Q000648:ultrastructure; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism*; D025261:Mitochondrial Proton-Translocating ATPases / Q000235:genetics / Q000378:metabolism*; D008953:Models, Anatomic; D020836:Protein Structure, Quaternary; D006180:Proton-Translocating ATPases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*
C503883:ATP20 protein, S cerevisiae; D004272:DNA, Mitochondrial; C542160:Fcj1 protein, S cerevisiae; D024101:Mitochondrial Proteins; D029701:Saccharomyces cerevisiae Proteins; D025261:Mitochondrial Proton-Translocating ATPases; C102550:TIM11 protein, S cerevisiae; D006180:Proton-Translocating ATPases