Atg9 cycling: The molecular mechanisms of anterograde and retrograde Atg9 trafficking

Abstract

Autophagy is a cellular catabolic pathway and plays an important role in various diseases such as cancer and neurodegeneration. In autophagy, there is the formation of an double-membrane vesicle called the autophagosome. The only currently known protein responsible for membrane delivery to the phagophore assembly site, where the autophagosome is formed, is Atg9. Atg9 cycles between its reservoirs and the PAS, but the mechanisms of this cycling are poorly understood. Here, I discuss what is currently known about the anterograde and retrograde of Atg9 trafficking in yeast and compare it with trafficking in mammalian cells. Finally, I show a few experiments which provide data on Atg18, one of the proteins involved in the retrograde transport of Atg9.