OSR2  is a 312 amino acid protein that contains five zinc finger domains. It is expressed in the kidneys, skeletal muscle, testis, and mouse embryos and may be involved in transcriptional activity and osteoblast function. The expression of OSR2 is regulated by C/EBP regulatory elements. OSR2 plays a role in regulating palatal development and expression of alkaline phosphatase. Two isoforms, OSR2A and OSR2B, are produced due to alternative splicing. OSR2B is 36 amino acids shorter than OSR2A and contains only three zinc finger motifs. Both isoforms localize to the nucleus and are thought to exhibit opposite transcriptional activities. Mutations in the gene encoding OSR2 can alter the gene expression of Pax-9 and TGF beta3.