AAV with Enh358MCK promoter driven TdTomato

This AAV expresses TdTomato driven by a muscle Enh358MCK promoter.

Muscle creatine kinase (MCK) is highly active in all striated muscles. MCK is the most abundant non-mitochondrial mRNA that is expressed in all skeletal muscle fiber types and is also highly active in cardiac muscle. The main regulatory regions in the murine MCK gene include a 358 bp proximal promoter and a muscle-specific, 200bp enhancer located approximately 1.1 kb away from the transcription start site. The muscle-specific enhancer contains 2 copies of E-Boxes, which are believed to be critical for the enhancer activity. Enh358MCK (Enh stands for enhancer, and 358MCK stands for the 358bp MCK proximal promoter) is constructed by ligating the ~200bp enhancer with the 358 bp proximal promoter of the murine MCK gene. This artificial promoter of about 0.6 Kb displays more or less the same activity as that of the full length 1.3 Kb MCKpromoter.

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.