Recombinant fission yeast cells and methods of using them are described, which provide for identification of chemical and biological inhibitors or activators of a target exogenous phosphodiesterase (PDE). The invention provides, in some aspects, compounds that inhibit cAMP PDE activity and compositions that include such compounds. The invention, in part, also includes methods of using cAMP PDE-inhibiting compounds in the treatment of cAMP PDE-associated diseases and/or disorders.
