A knock‐in allele of Hand2 expressing Dre recombinase

Abstract

SummaryHAND2 is a basic helix–loop–helix transcription factor with diverse functions during development. To facilitate the investigation of genetic and functional diversity among Hand2‐expressing cells in the mouse, we have generated Hand2Dre, a knock‐in allele expressing Dre recombinase. To avoid disrupting Hand2 function, the Dre cDNA is inserted at the 3′ end of the Hand2 coding sequence following a viral 2A peptide. Hand2Dre homozygotes can therefore be used in complex crosses to increase the proportion of useful genotypes among offspring. Dre expression in mid‐gestation Hand2Dre embryos is indistinguishable from wild‐type Hand2 expression, and HandDre efficiently recombines rox target sites in vivo. In combination with existing Cre and Flp mouse lines, Hand2Dre will therefore extend the ability to perform genetic intersectional labeling, fate mapping, and functional manipulation of subpopulations of cells characterized by developmental expression of Hand2.