Autophagosome

An autophagosome is a unique, double-membraned organelle that is a key component of macroautophagy (a type of autophagy). It's formation is the first step in autophagy after the genesis of a phagophore, and it mediates the sequestering of cytosolic macromolecules. It precedes the formation of an autolysosome, where a lysosome bonds to the autophagosome.