Yeast Vps13 promotes mitochondrial function and is localized at membrane contact sites

Area of Science:

• Cell Biology
• Molecular Biology
• Genetics

Background:

• The Vps13 protein family is vital in eukaryotic cells, with mutations linked to diseases like chorea acanthocytosis (ChAc).
• The precise cellular roles of Vps13 proteins remain incompletely understood, although yeast Vps13 is involved in vacuolar protein sorting and sporulation.

Purpose of the Study:

• To elucidate the cellular functions of Vps13 proteins, particularly their role in mitochondrial integrity.
• To investigate the localization and function of Vps13 at membrane contact sites.
• To explore the connection between Vps13 mutations and Chorea Acanthocytosis.

Main Methods:

• Utilizing yeast models to study Vps13 function.
• Investigating Vps13's role in mitochondrial integrity, DNA transfer, and mitophagy.
• Analyzing Vps13 localization at endosome-mitochondrion and nuclear-vacuole contact sites.
• Assessing the functional impact of Chorea Acanthocytosis-associated VPS13A mutations in yeast.

Main Results:

• VPS13 is essential for maintaining mitochondrial integrity, preventing mitochondrial DNA transfer to the nucleus, and suppressing mitophagy.
• Vps13 localizes to endosome-mitochondrion contacts and nuclear-vacuole junctions, indicating a role at membrane contact sites.
• VPS13 functions in parallel with the endoplasmic reticulum-mitochondrion encounter structure (ERMES).
• Chorea Acanthocytosis-associated VPS13A mutations impair Vps13's ability to compensate for the loss of ERMES.

Conclusions:

• Vps13 operates at multiple membrane contact sites, and its specific localization is critical for distinct cellular functions.
• Loss of Vps13 function at specific membrane contact sites may explain separation-of-function phenotypes.
• Mitochondrial dysfunction arising from impaired Vps13 function is a potential basis for Chorea Acanthocytosis.