Ubiquitin facilitates a quality-control pathway that removes damaged chloroplasts
Year: 2015
Type: article
Abstract: Energy production by chloroplasts and mitochondria causes constant oxidative damage. A functioning photosynthetic cell requires quality-control mechanisms to turn over and degrade chloroplasts damaged by reactive oxygen species (ROS). Here, we generated a conditionally lethal Arabidopsis mutant that accumulated excess protoporphyrin IX in the chloroplast and produced singlet oxygen. Damaged chloroplasts were subsequently ubiquitinated and selectively degraded. A genetic screen identified the plant U-box 4 (PUB4) E3 ubiquitin ligase as being necessary for this process. pub4-6 mutants had defects in stress adaptation and longevity. Thus, we have identified a signal that leads to the targeted removal of ROS-overproducing chloroplasts.
Source: Science
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
Funders: Howard Hughes Medical Institute, U.S. Department of Energy, W. M. Keck Foundation, Deutsche Forschungsgemeinschaft, Max-Planck-Gesellschaft, National Institutes of Health, National Cancer Institute, National Institute of General Medical Sciences, National Institute of Neurological Disorders and Stroke
Awards: G114280915, Mechanisms of Rapid Alkalinization Factor Induced Growth Arrest in Arabidopsis, Salk Institute for Biological Studies NINDS Center Core Grant, G4384710278, G5151191652, SIGNAL TRANSDUCTION PATHWAYS THAT REGULATE CAB GENE EXPRESSION, G9000267921, Cancer Center Support Grant (CCSG), G961475428
OpenAlex ID: W2171984357