The molecular pathway of Autophagy. Due to the microenvironmental stress, AMP-activated protein kinase (AMPK) is activated, leading to the activation of ULK-1 complex (ULK-1, ATG13, ATG101, and FIP200). ULK-1 complex activation leads the assembly of Class III Phosphoinositide 3-kinases (PI3Ks) (Beclin-1, Vps34, AMBRA, p150, and ATG14). Both ULK-1 complex and Class III PI3K translocate to the nucleation site and stimulate the establishment of the isolation membrane known as the phagophore. Elongation of the phagophore befalls via the effect of ATG5-ATG12-ATG16 and LC3-II until a double membrane vesicle is formed, known as the autophagosome. Autophagosomes fuse with the lysosome, which leads to degradation of cargo via the effect of lysosomal enzymes with release of biomolecules.