First Author | Liu Y | Year | 2015 |
Journal | J Biol Chem | Volume | 290 |
Issue | 19 | Pages | 11843-52 |
PubMed ID | 25778398 | Mgi Jnum | J:279947 |
Mgi Id | MGI:6368091 | Doi | 10.1074/jbc.M114.629931 |
Citation | Liu Y, et al. (2015) The Proapoptotic F-box Protein Fbxl7 Regulates Mitochondrial Function by Mediating the Ubiquitylation and Proteasomal Degradation of Survivin. J Biol Chem 290(19):11843-52 |
abstractText | Fbxl7, a component of the Skp1.Cul1.F-box protein type ubiquitin E3 ligase, regulates mitotic cell cycle progression. Here we demonstrate that overexpression of Fbxl7 in lung epithelia decreases the protein abundance of survivin, a member of the inhibitor of apoptosis family. Fbxl7 mediates polyubiquitylation and proteasomal degradation of survivin by interacting with Glu-126 within its carboxyl-terminal alpha helix. Furthermore, both Lys-90 and Lys-91 within survivin serve as ubiquitin acceptor sites. Ectopically expressed Fbxl7 impairs mitochondrial function, whereas depletion of Fbxl7 protects mitochondria from actions of carbonyl cyanide m-chlorophenylhydrazone, an inhibitor of oxidative phosphorylation. Compared with wild-type survivin, cellular expression of a survivin mutant protein deficient in its ability to interact with Fbxl7 (E126A) and a ubiquitylation-resistant double point mutant (KK90RR/KK91RR) rescued mitochondria to a larger extent from damage induced by overexpression of Fbxl7. Therefore, these data suggest that the Skp1.Cul1.F-box protein complex subunit Fbxl7 modulates mitochondrial function by controlling the cellular abundance of survivin. The results raise opportunities for F-box protein targeting to preserve mitochondrial function. |