Mitochondrial Sterol Oxidation Marks the Spot Lilian Lamech, Cole M. Haynes Molecular Cell Volume 68, Issue 4, Pages 641-642 (November 2017) DOI: 10.1016/j.molcel.2017.11.003 Copyright © 2017 Elsevier Inc. Terms and Conditions
Figure 1 ROS-Modified Lipid Targets Vms1 to Stressed Mitochondria for Ribosome Rescue A component of the ribosome quality control pathway, Vms1, is recruited selectively to dysfunctional mitochondria by the sterol, ergosterol peroxide. In the absence of stress, a leucine-rich sequence (LRS) on Vms1 masks a binding pocket containing the mitochondrial-targeting domain (MTD), which targets Vms1 to mitochondria. Dysfunctional mitochondria produce reactive oxygen species (ROS), which react with ergosterol to produce ergosterol peroxide in the outer mitochondrial membrane. Ergosterol peroxide competes with the LRS to bind and recruit Vms1 to mitochondria in order to participate in recycling mitochondria-localized stalled ribosomes and degradation of the aberrant protein products. At the mitochondrion, Vms1 inhibits Rqc2 CAT-tailing activity so that aberrant proteins can be successfully degraded in the matrix rather than aggregating. Molecular Cell 2017 68, 641-642DOI: (10.1016/j.molcel.2017.11.003) Copyright © 2017 Elsevier Inc. Terms and Conditions