On the activation of phosphodiesterase by a 26 kDa protein.
The effects of a 26 kDa protein isolated from vertebrate retina rod outer segments (ROS) and its reconstituted analog on the phosphodiesterase (PDE) activity and cGMP-dependent conductance have been studied [Nature 313 (1985) 310-313]. Using the patch-clamp technique it was shown that the 26 kDa protein in concentrations up to 1 microM accelerates hydrolysis of cGMP by near-membrane PDE by 1-2 orders of magnitude. This process is suggested to be mediated by some intracellular agent. At the same concentrations the 26 kDa protein was shown to inhibit cGMP-dependent conductance of the photoreceptor membrane. A possible role of these effects in the processes of phototransduction and adaptation is discussed.
Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region.
S S
SS
Nikonov
G N
GN
Filatov
E E
EE
Fesenko
D000818:Animals; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D006152:Cyclic GMP / Q000378:metabolism; D004789:Enzyme Activation; D005136:Eye Proteins / Q000378:metabolism*; D006868:Hydrolysis; D008564:Membrane Potentials; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism*; D051603:Recoverin; D012374:Rod Cell Outer Segment / Q000201:enzymology / Q000502:physiology; D014982:Xenopus laevis
D002135:Calcium-Binding Proteins; D005136:Eye Proteins; C067574:RCV1 protein, Bos taurus; D051603:Recoverin; D010727:Phosphoric Diester Hydrolases; D006152:Cyclic GMP