AAV with CAG promoter driven TdTomato

This AAV expresses TdTomato driven by an ubiquitous CAG promoter.

The roughly 1.8Kb CAG promoter (also known as CBA promoter or CAGGS promoter) is a strong synthetic promoter frequently used to drive high levels of gene expression in mammalian cells. The CAG promoter is composed of the following regulatory elements: (C) cytomegalovirus (CMV) early enhancer element; (A) the promoter region, the first exon, and the first intron of chicken beta-Actin gene, and (G) the splice acceptor of the rabbit beta-Globin gene. Like the EF1a promoter, the CAG promoter is commonly used as an alternative for the CMV promoter, from which the expression is decreased due to methylation/silencing. In many cell types tested, the CAG and EF1a promoters give much higher levels of expression than other commonly used cellular promoters such as the UBC and PGK promoters.

dTomato belongs to a family of fluorescent proteins called mFruit. Two dTomato units were joined head-to-tail through a linker, yielding a tandem dimer fluorescent protein, tdTomato. The tdTomato derivative is the brightest fluorescent protein yet reported, featuring an orange-red emission maximum at 581nm and is one of the most photo-stable fluorescent proteins. Other fluorescent proteins with similar emission spectra include DsRed, DsRed2, TurboRFP, TagRFP, and TagRFP-T.