Affinities of bovine photoreceptor cGMP phosphodiesterases for rod and cone inhibitory subunits

FEBS Letters

Hamilton, Susan E.¹  Prusti, Rabi K.²  Bentley, J.Kelley¹  Beavo, Joseph A.¹  Hurley, James B.¹ 

[1] Department of Biochemistry and Howard Hughes Medical Institute, SL-15 University of Washington, Seattle, WA 98195, USA;Curative Technologies Inc., E. Setauket, NY 11733, USA

关键词: Retinal phosphodiesterase;    Inhibition;    Cyclic GMP;    Bovine retina;    cGMP;    guanosine 3';    5'-cyclic monophosphate;    HPLC;    high pressure liquid chromatography;    PAGE;    polyacrylamide gel electrophoresis;    PDE;    phosphodiesterase;    PMSF;    phenylmethylsulfonyl fluoride;    SDS;    sodium dodecyl sulfate;   

DOI  :  10.1016/0014-5793(93)80012-J

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Rods and cones have analogous phototransduction components and cycles, but differ from each other in their physiological response to light. Differences between the affinities of rod and cone phosphodiesterase (PDE) catalytic subunits for their respective inhibitory subunits could potentially contribute to these physiological differences. To test this idea, we expressed both the 13 kDa PDE subunit, unique to a subset of bovine retinal cones [(1990) J. Biol. Chem. 265, 11259-11264], and the rod PDE 11 kDa inhibitory subunit in E. coll, purified them, and compared their abilities to inhibit rod and cone PDE catalytic subunits. Rod PDE has similar K _i values (~80 pM) for both the rod and cone recombinant inhibitory subunits. Activated cone PDE has K _i values of 200 pM for the cone 13 kDa subunit and 600 pM for rod PDEγ.

【 授权许可】

Unknown