Mitochondrial cristae shape determines respiratory chain supercomplexes assembly and respiratory efficiency

Respiratory chain complexes assemble into functional quaternary structures called supercomplexes (RCS) within the folds of the inner mitochondrial membrane, or cristae. Here, we investigate the relationship between respiratory function and mitochondrial ultrastructure and provide evidence that cristae shape determines the assembly and stability of RCS and hence mitochondrial respiratory efficiency. Genetic and apoptotic manipulations of cristae structure affect assembly and activity of RCS in vitro and in vivo, independently of changes to mitochondrial protein synthesis or apoptotic outer mitochondrial membrane permeabilization. We demonstrate that, accordingly, the efficiency of mitochondria-dependent cell growth depends on cristae shape. Thus, RCS assembly emerges as a link between membrane morphology and function.We thank A. Gross (Weizmann Institute) for anti-BID antibody, A. Latorre-Pellicer (CNIC) for mtDNA RT-PCR, and M. Albiero (VIMM) for tail vein injections. L.S. is a senior scientist of the Dulbecco-Telethon Institute. This work is supported by Telethon Italy (GGP12162, GPP10005B, and TCR02016), AIRC Italy, MOH Italy (GR 09.021), and Swiss National Foundation (31-118171). J.A.E. is supported by MINECO (SAF2012-32776 and CSD2007-00020), DGA (B55, PIPAMER O905), and CAM (S2011/BMD-2402). S.C. was supported by a Journal of Cell Science Travelling Fellowship. C.F. was supported by an AIRC Biennial Fellowship. The CNIC is funded by the Instituto de Salud Carlos III-MICINN and the Pro-CNIC Foundation.S