Abstract
The GTP-binding subunit of transducin (T alpha) activates the cGMP phosphodiesterase (PDE) of bovine retinal rods by relieving the constraint imposed by the inhibitory subunit PDE gamma. We have isolated and characterized the complex T alpha.GTP gamma S-PDE gamma formed when T alpha is activated by the nonhydrolyzable analog GTP gamma S. Sedimentation and light-scattering techniques demonstrate that, in contrast to free T alpha.GTP gamma S, which is soluble, the T alpha.GTP gamma S-PDE gamma complex, as well as T alpha.GTP-PDE gamma, is membrane bound at cytosolic ionic strength. It is eluted from the membrane at low ionic strength as a monomeric and 1:1 stoichiometric complex. The relative affinities of PDE gamma for PDE alpha beta and for T alpha.GTP are discussed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.