Human COX7A2L Regulates Complex III Biogenesis and Promotes Supercomplex Organization Remodeling without Affecting Mitochondrial Bioenergetics.

ABSTRACT: The mitochondrial respiratory chain is organized in a dynamic set of supercomplexes (SCs). The COX7A2L protein is essential for mammalian SC III₂+IV assembly. However, its function in respirasome (SCs I+III₂+IV_n) biogenesis remains controversial. To unambiguously determine the COX7A2L role, we generated COX7A2L-knockout (COX7A2L-KO) HEK293T and U87 cells. COX7A2L-KO cells lack SC III₂+IV but have enhanced complex III steady-state levels, activity, and assembly rate, normal de novo complex IV biogenesis, and delayed respirasome formation. Nonetheless, the KOs have normal respirasome steady-state levels, and only larger structures (SCs I_1-2+III₂+IV_2-n or megacomplexes) were undetected. Functional substrate-driven co

SUBMITTER: Lobo-Jarne T 

PROVIDER: S-EPMC6286155 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature