A current view of molecular dissection in autophagy machinery

Macroautophagy (hereafter called autophagy) is a highly conserved lysosomal pathway for catabolism of intracellular material in eukaryotic cells. Autophagy is also an essential homeostatic process through which intracellular components are recycled for reuse or energy production. The extremely regulated autophagy process begins with the formation of hallmarked double membrane bound organelles called autophagosomes which in turn fuse with lysosomes called autolysosomes and finally degrade the autophagic cargos. The multistages molecular machinery of autophagy is critically orchestrated by the action of a set of the autophagy proteins (Atg) and a supreme regulator, mTOR (mechanistic target of rapamycin). However, individual stages of autophagy are mechanistically complex and partially understood. In this review, the individual stages of autophagy are dissected, and the corresponding molecular regulation is discussed in view of current scientific knowledge of autophagy. This understanding of sequential events of autophagy machinery through this review may lead to great interest in the therapeutic potential for manipulating of autophagy in established diseases.