Phosphodiesterase 8B (PDE8B)

Mammalian PDEs have been grouped into several families based on substrate affinities, inhibitor sensitivities, mode of regulation, and amino acid sequence homologies. The PDE8 family contains high-affinity cAMP-specific, IBMX (3-isobutyl-1-methyl-xanthine)-insensitive PDEs, such as PDE8B. All PDEs share a conserved C-terminal catalytic region and a variable N-terminal domain that presumably accounts for the distinctive regulatory properties unique to the individual families.Abundantly expressed in the thyroid. Also very weakly expressed in brain, spinal cord and placenta. In the thyroid isoform 1 predominates, and isoforms 2 and 6 are also highly expressed. In the placenta isoforms 1 and 2 are expressed equally. In the brain isoform 2 predominates.