Branch site mutated mice revealed distinct roles of two Runx2 isoforms in bone development (opens in new tab)

Runx2 is a key regulator of osteoblast differentiation and chondrocyte maturation. However, the distinct functions of the two functional isoforms remain to be clarified. Transcription of two isoforms, Runx2-I and Runx2-II, starts from the proximal and distal promoters upstream of exons 2 and 1, respectively. To investigate the functions of the two isoforms, we generated a novel mouse model (Runx2-brmut/mut), in which intron 1 splicing for Runx2-II was disrupted by mutating the branch site ess...