Data for: Quantitative analysis of autophagy reveals the role of ATG9 and ATG2 in autophagosome formation

Autophagy is a catabolic pathway required for the recycling of cytoplasmic
materials. To define the mechanisms underlying autophagy it is critical to
quantitatively characterize the dynamic behavior of autophagy factors in
living cells. Using a panel of cell lines expressing HaloTagged autophagy
factors from their endogenous loci, we analyzed the abundance,
single-molecule dynamics, and autophagosome association kinetics of a wide
variety of autophagy proteins involved in autophagosome biogenesis.
Surprisingly, autophagosome formation is inefficient and requires
ATG2-mediated tethering to donor membranes. Furthermore, our observations
support the model that phagophores are initiated by the accumulation of
autophagy factors on mobile ATG9 vesicles, and that the ULK1 complex and
PI3-kinase form a positive feedback loop required for autophagosome
formation. Finally, we demonstrate that the duration of autophagosome
biogenesis is approximately 110 seconds. In total, our work provides
quantitative insight into autophagosome biogenesis and establishes an
experimental framework to analyze autophagy in human cells.