AAV with ALB(1.9) promoter driven roGFP1

This AAV expresses roGFP1 driven by a liver ALB(1.9) promoter.

The ALB(1.9) is a synthetic promoter of ~1.9 Kb. It is based on the human Albumin promoter as well as several other regulatory elements. This synthetic promoter gives an extremely high level of long-term, liver-specific transgene expression that is 100-100 fold greater than that of the CMV promoter. For short-term (1-2 weeks post-injection into mouse liver), ALB(1.9) gives comparable expression relative to that of the CMV promoter. However, the expression level of the CMV promoter decreases 100-1000 fold from its peak level within 10-20 weeks of DNA administration whereas the ALB(1.9) promoter sustains its initial high level of expression for over 1 year. Compared to the regular ALB promoter, which is also commonly used for liver-specific transgene expression, the expression level from ALB(1.9) is about 10-100 fold greater.

roGFP1 is a reduction-oxidation sensitive green fluorescent protein used as a biosensor. Two cysteines were introduced into the beta-barrel structure of GFP; the oxidation state, reduced dithiol or the oxidized disulfide, of the engineered thiols determines the fluorescent properties of the sensor. roGFPs (roGFP1 and roGFP2), have two fluorescent excitation maxima at about 400 and 490 nm, respectively and display rapid and reversible ratiometric changes in fluorescence in response to changes in redox potential in vitro and in vivo.