Elucidating the Molecular Mechanism of Macroautophagy in Aging Dietary Restriction Utilizing an Integrated Mouse Genetic-proteomic Approach

Autophagy, the lysosomal pathway for degrading long-lived proteins, protein aggregates and damaged organelles, decreases in aged cells and tissues. Defects in autophagy are implicated in many age-related diseases, and inducing autophagy prolongs lifespan in mice. Despite the importance of autophagy in aging and age-related diseases, the mammalian autophagy pathway is far from understood. We propose to uncover molecular component(s) of the autophagy pathway modulating lifespan that are mediated through a tightly­ regulated and context-dependent protein network. Beclin 1 is a key mammalian autophagy regulator known to have an anti-aging role. Utilizing a novel integrated mouse genetic-proteomic approach, we successfully identified two novel Seclin 1 interactors as positive and negative autophagy regulators. In Aim 1, we will establish a context-dependent autophagy interactome to test the hypothesis that with age, Beclin 1 protein complexes change contributing to decreased autophagy. Since dietary restriction (DR) decelerates aging, likely through inducing autophagy, we will test in Aim 2 the hypothesis that Beclin 1 protein complexes change with acute DR in an age-dependent and tissue­ specific manner. For those Beclin 1 interactors showing age differences or differences with acute DR, we will modulate their expression levels to address their functions. By establishing a context-dependent mammalian autophagy interactome, this study will provide new insights into how the mammalian autophagy pathway changes with age and diet, and, identify potential target(s) for decelerating age-dependent decline of autophagy in aging and age-related diseases .