AAV with mIP2 promoter driven FLPo

This AAV expresses FLPo driven by an islet mIP2 promoter.

This promoter is based on the 1.1 Kb regulatory region of mouse pre-proinsulin II gene, also known as ins2, ins-2, ins-II, insulin-II, or Mody4. It is commonly used for beta cell-specific gene expression in the pancreatic islet. (m)INS2 promoter is also referred as the mIP2 or mIP2 promoter.

FLPo is a codon-optimized version of FLPe that greatly increases the protein expression and the FRT recombination efficiency in mouse cells. FLP is a site-specific recombinase (SSR) from the _ integrase family which recognizes distinct 34 bp FRT sites. Like Cre/LoxP system, the FLP/FRT system has been widely used for gene expression and generating conditional knockout mice, mediated by the FLP/FRT system. Initial use of FLP in mammalian cells revealed inefficient recombinase activity due to thermal instability of the FLP protein. Subsequent screening for thermostable mutants resulted in the identification of FLPe which has a 4-fold higher recombination efficiency at 37oC than original FLP. However, the recombination efficiency of FLPe in cells remains very low relative to other recombinases because of its non-mammalian origin. FLPo is engineered by codon optimization of FLPe, and gives much higher expression and activity than FLPe.