The transgene comprises a fusion cDNA encoding enhanced green fluorescent protein joined at its C-terminus to rat microtubule-associated protein 1 light chain 3 beta under control of the "CAG promoter" -- which consists of the cytomegalovirus immediate-early enhancer (CMV-EI) followed by a 1.3-kb DNA segment including the promoter, first exon and first intron of the chicken beta-actin gene, with the 3' splice junction sequence replaced by that of the rabbit hemoglobin beta gene -- and followed by the SV40 late polyadenylation signal. Expression of the transgene is observed during prenatal stages and in nearly all tissues of the adult mouse. Its level is similar to that of endogenous MAP1LC3B in brain, but significantly higher in other tissues. In liver of fed mice, it occurs diffusely throughout the cytoplasm; upon starvation, it becomes localized to isolation membranes and phagosomes. Cytoplamsic aggregations of this fusion protein indicate autophagic activity.
The transgene insertion site is located in the distal region of chromosome 2, 106 bp upstream of the Gm14314 locus.