Yeast Ataxin-2, A Protein with Many Friends: Identification of a Novel Role for Pbp1 in Mitochondrial Biogenesis

Mitochondria need to adapt quickly to environmental challenges to meet metabolic demands. Switching yeast cells from growth in a glycolytic to a respiratory environment forces the cell to use mitochondrial respiration, and as a result, mitochondrial biogenesis is induced. Puf3 functions as a glucose sensor in yeast to support mitochondrial biogenesis in respiratory conditions. It facilitates a rapid stabilization of its target transcripts, such as cytochrome c oxidase components. Yeast-Ataxin2, Pbp1, is a poly(A)tail binding protein and a negative regulator of TORC1. Previous work showed that cells lacking Pbp1 in respiratory conditions exhibited mitochondrial dysfunction. I thus hypothesized that Pbp1 has an essential role in mitochondrial respiration. Utilizing genetics and biochemical assays, I discovered that loss of Pbp1 leads to decreased Puf3-specific mitochondrial proteins, suggesting a functional relationship between Pbp1 and Puf3. I also found that Pbp1 stabilizes and promotes Puf3-target mRNAs in respiratory conditions using a Puf3 reporter assay. Lastly, I showed genetic and physical interaction between Pbp1 and Puf3 through their low complexity domains. These findings provide clear evidence that Pbp1 works together with Puf3 to regulate mitochondrial biogenesis. It also sets the stage to investigate whether similar mechanisms for Ataxin2 in mitochondrial biogenesis exist.

Author dc:creator

• van de Poll, Floortje Paulien

Contributors dc:contributor

• Wang, Fei
• Kohler, Jennifer J.
• Nijhawan, Deepak
• Tu, Benjamin

• Mitochondria
• RNA-Binding Proteins
• Saccharomyces cerevisiae
• Saccharomyces cerevisiae Proteins
• Carrier Proteins

Language dc:language

en

Identifier

1482732364

OAI identifier oai:identifier

oai:utswmed-ir.tdl.org:2152.5/10440