Smouse testis pdha-2 promoter upstream sequences confer tissue- and temporal-specific activity in transgenic mice

Spermatogenesis is a complex process requiring the coordinate expression of a number of testis-specific genes. One of these, Pdha-2, codes for the murine testis-specific isoform of the Ela subunit of the pyruvate dehydrogenase complex. To elucidate the mechanisms regulating its expression in vivo, we have begun to investigate the Pdha-2 promoter in transgenic mice. In this paper, a construct containing 3 • 0 kb of promoter and upstream sequences is reported to be sufficient for directing the testis-specific expression of a CAT reporter gene in mice harbouring the transgene. Similarly to the endogenous Pdha-2, the CAT gene is expressed in testis in a stage-specific manner. However, the 3-0-kb Pdha-2 promoter is not active in somatic tissue suggesting that repressor elements may be present within these sequences.