Striatum‐ and testis‐specific phosphodiesterase PDE10A

Abstract

PDE10A, a phosphodiesterase (PDE) exhibiting properties of a cAMP PDE and a cAMP‐inhibited cGMP PDE, was cloned and investigated in detail in rats. PDE10A transcripts were abundant in the brain and testis. In situ hybridization analysis using a PDE10A riboprobe demonstrated the presence of PDE10A transcripts in the neurons of the striatum and the olfactory tubercle regions of the brain. Rat PDE10A cDNAs were isolated from a brain cDNA library and nucleotide sequence analysis revealed several N‐terminal variants. The deduced amino‐acid sequence of one of the major variant forms contained 794 amino acids, and it was 96% identical to that of the human PDE10A2. The other major form has a distinct N‐terminal sequence that is not found in humans. PDE10A was partially purified from rat striatum and testis, and characterized with respect to K m , inhibitor sensitivity and immunoreactivity to an anti‐PDE10A serum. These findings indicate that PDE10A functions in these tissues.