In short, GFP-ATG8. GFP is a protein in the jellyfish Aequorea Victori that exhibits bright green fluorescence when excited at a wavelength of 488nm and has an emission peak at about 507nm ( blue to ultraviolet range).
GFP is served as biological marker for monitoring physiological processes, visualizing protein localization, and detecting transgenic expression.
GFP consists of 238 amino acid with 27 kilo Dalton of the protein size. When ATG8 fused to GFP (GFP-ATG8), the ATG8 here as a protein of interest (ATG8 is a ubiquitin-like protein required for the formation of autophagosomal membranes) to carry the GFP which used as a reporter and exhibit green signal.
GFP-ATG8 will serve as a protein visualized marker gene which localized on the double membrane vesicle, the autophosome.