Immunologic characterization of the photoreceptor outer segment cyclic GMP phosphodiesterase

J Biol Chem. 1984 Jul 10;259(13):8612-8.

Abstract

High affinity (KD approximately 1 X 10(-9) M) monoclonal antibodies (ROS-1 and ROS-2) were prepared to bovine photoreceptor outer segment cGMP phosphodiesterase. ROS-1 immunoadsorbed greater than 95% of the cGMP phosphodiesterase activity from a detergent-solubilized bovine retina extract while ROS-2 immunoadsorbed only a subfraction of the same activity. Sodium dodecyl sulfate gel analysis of these immunoadsorbates demonstrated that ROS-1 and ROS-2 specifically adsorbed only peptides that comigrated with purified rod outer segment phosphodiesterase. Limited trypsin digestion of purified rod outer segment phosphodiesterase greatly reduced its affinity for ROS-1 but not ROS-2. When a crude heat-stable inhibitor fraction was added back to the activated enzyme, the affinity for ROS-1 was restored, suggesting that the inhibitor was necessary for ROS-1 binding. ROS-1 but not ROS-2 was found to inhibit cGMP phosphodiesterase which had been activated either by dilution or guanyl nucleotide. The inhibitory property of ROS-1 may provide a useful probe for directly studying the effects of this phosphodiesterase on the phototransduction response in the retina. Sodium dodecyl sulfate gel analysis demonstrated that the ROS-1 immunoadsorbates from mammals, fish, and amphibia contained peptides of similar mobility. Immunocytochemistry performed with ROS-1 and fluorescein isothiocyanate-conjugated rabbit anti-mouse IgG localized the antigenic determinant to both rod and cone outer segments suggesting the presence of an antigenically similar phosphodiesterase in both types of photoreceptors.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 3',5'-Cyclic-GMP Phosphodiesterases / metabolism*
  • Animals
  • Antibodies, Monoclonal* / isolation & purification
  • Antigen-Antibody Complex
  • Cattle
  • Fluorescent Antibody Technique
  • Immunoglobulin G / isolation & purification
  • Kinetics
  • Photoreceptor Cells / enzymology*
  • Rod Cell Outer Segment / enzymology*

Substances

  • Antibodies, Monoclonal
  • Antigen-Antibody Complex
  • Immunoglobulin G
  • 3',5'-Cyclic-GMP Phosphodiesterases