mitochondria

Viewing posts tagged mitochondria

Study reveals the protein machinery central to CoQ trafficking in yeast

Beyond its role in mitochondrial bioenergetics, Coenzyme Q (CoQ, ubiquinone) serves as a key membrane-embedded antioxidant throughout the cell. However, how CoQ is moved from its site of synthesis on the inner mitochondrial membrane to other sites remains a longstanding mystery. In a recent study, researchers identified two highly conserved but poorly characterized mitochondrial proteins that affect this process. Their results reveal the protein machinery central to CoQ trafficking in yeast and lend insights into the broader interplay between mitochondria and the rest of the cell.

Read the article: UbiB proteins regulate cellular CoQ distribution in Saccharomyces cerevisiae

NCQBCS Scientists Publish on Essential Phosphatase Pptc7

Niemi et al analyzed a Pptc7 matrix phosphatase in mice in a recent issue of Nature Communications.

This paper addressed the functionality of phosphorylation in mitochondrial proteins. While mitochondrial proteins tend to have a lot of phosphorylation, it is also possible that protein dephosphorylation (the opposite process) may be significant in controlling various mitochondrial processes.

To test this, researchers deleted the matrix phosphatase Pptc7 from mice using the CRISPR-Cas9. As a result, mice were born with normal transcript levels but less mitochondria and protein in their tissues. They also had more phosphorylation in certain mitochondrial proteins. These mice developed hypoketonic hypoglycemia, had higher levels of acylcarnitines and serum lactate, and died shortly after being born. 

Analyzing this data, researchers pinpointed that the protein translocase complex subunit Timm50 is probably a Pptc7 substrate whose phosphorylation lowers import activity.  This data also demonstrates that Pptc7 is necessary for healthy mammalian mitochondrial processes, such as metabolism, and biogenesis after birth.