Conserved role of ENDOG in promoting autophagy.

ENDOG (endonuclease G), a mitochondrial endonuclease, is known to participate in apoptosis and paternal mitochondria elimination. However, the role and underlying mechanism of ENDOG in regulating macroautophagy remain unclear. We recently reported that ENDOG released from mitochondria promotes autophagy during starvation, which we demonstrated is evolutionarily conserved across species by performing experiments in human cell lines, mice, Drosophila, and C. elegans. This study demonstrates that ENDOG can be phosphorylated by GSK3B, which enhances the interaction between ENDOG with YWHAG and leads to the release of TSC2 and PIK3C3 from YWHAG, followed by MTOR pathway suppression and autophagy initiation. Additionally, the endonuclease activity of ENDOG is essential for activating the DNA damage response and thus inducing autophagy. Consequently, this study uncovered an exciting new role for ENDOG as a crucial regulator of autophagy.