Author response: Selective sorting and destruction of mitochondrial membrane proteins in aged yeast
Year: 2016
Type: peer-review
Abstract: Our cells contain compartments called mitochondria, which provide energy and serve as a home for many metabolic pathways that are critical for life. Changes in mitochondrial activity can contribute to aging and to the development of several age-associated diseases. However, our cells contain systems that detect changes in the performance of mitochondria and can act to re-establish a healthy state. These systems respond to stress or changes in metabolism by degrading particular proteins in the mitochondria. This enables damaged or unwanted proteins to be replaced with new proteins, but it is not clear how these mitochondrial defense systems work to keep mitochondria healthy as an organism ages. Budding yeast is a good model in which to study the aging process because the performance of this yeast’s mitochondria change in a characteristic way as the yeast ages. Previous studies have shown that these changes are caused by alterations in another cell structure called the lysosome, which can store nutrients and is where many proteins are degraded. Here, Hughes et al. used yeast cells to investigate how mitochondrial defense systems operate during aging. The experiments reveal an entirely new mitochondrial protein degradation system that helps to keep the mitochondria healthy as the yeast cells age. This process is rapidly triggered by changes in lysosome activity and results in certain proteins in each mitochondrion being sorted into a small compartment made from a part of the mitochondrion. This compartment is released from the mitochondrion and then travels to the lysosome where the proteins are destroyed. Inhibiting the formation of these compartments results in mitochondria being more sensitive to cellular stress. The next steps following on from this work are to find out exactly what role this mitochondrial defense pathway plays in cells and why it targets only a small set of all the proteins found in mitochondria.
Institutions: University of Utah, Fred Hutch Cancer Center
Language: English
Subfield: Epidemiology
Field: Medicine
Domain: Health Sciences
Open Access status: gold
OpenAlex ID: W2985340548