The roles of a mitochondrial protein Miga in autophagy

Lingna Xu; Liquan Wang; Chao Tong

doi:10.1080/15548627.2022.2153569

The roles of a mitochondrial protein Miga in autophagy

Autophagy. 2023 Jul;19(7):2151-2152. doi: 10.1080/15548627.2022.2153569. Epub 2022 Dec 5.

Authors

Lingna Xu^{1

2}, Liquan Wang¹, Chao Tong^{1

2}

Affiliations

¹ Department of Obstetrics, Life Sciences Institute, the Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China.
² MOE Key Laboratory for Biosystems Homeostasis & Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou, China.

Abstract

Miga is an evolutionarily conserved protein that localizes to the outer membrane of mitochondria and mediates endoplasmic reticulum (ER)-mitochondrial contacts through interaction with VAP proteins in the ER. We recently reported that Miga is required for autophagosome-lysosome fusion during macroautophagy/autophagy. Miga binds to Atg14 and Uvrag, two alternative subunits of the class III phosphatidylinositol 3-kinase (PtdIns3K) complex. Miga regulates phosphatidylinositol-3-phosphate (PtdIns3P) levels through its interaction with Uvrag and its ER-mitochondrial contact site (ERMCS) tethering activity. Miga stabilizes Atg14, which maintains steady levels of the SNARE protein, Syx17. We propose that Miga establishes a direct link between mitochondria and autophagy to maintain cellular homeostasis.

Keywords: Autophagy; drosophila; endoplasmic reticulum-mitochondrial contacts; mitochondrion; phosphatidylinositol-3 kinase.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Autophagy* / physiology
Autophagy-Related Proteins / metabolism
Endoplasmic Reticulum / metabolism
Mitochondrial Proteins* / metabolism
SNARE Proteins / metabolism

Substances

Mitochondrial Proteins
SNARE Proteins
Autophagy-Related Proteins

Grants and funding

This work was supported by the National Natural Science Fundation of China [92157201, 92254305, 32030027, 91754103]; National Natural Science Foundation of China [32200593].