Nitric oxide-regulated endogenous ADP-ribosylation of rod outer segment proteins.
Both membrane and cytosolic fractions of retinal rod outer segments contain ADP-ribosylases that modify proteins in the respective fractions. Nitroprusside and endogenously produced NO regulate the activities of these ADP-ribosylases. The ADP-ribosylation of the membrane proteins of molecular weight 116K, 66K and 46K is inhibited by NO and nitroprusside, while that of the 38K cytosolic protein and the 39K membrane-associated protein is activated. The 39K protein is identified as the alpha-subunit of G-protein. The ADP-ribosylation of this protein is activated 6 to 11-fold by NO suggesting that NO may play a significant role in modulating the activity of G-protein in visual transduction.
Pozdnyakov
N
N
Eye Research Institute, Oakland University, Rochester, MI 48309.
Lloyd
A
A
Reddy
V N
VN
Sitaramayya
A
A
D000246:Adenosine Diphosphate Ribose / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D003600:Cytosol / Q000378:metabolism; D005136:Eye Proteins / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000378:metabolism; D066298:In Vitro Techniques; D008565:Membrane Proteins / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D009599:Nitroprusside; D012374:Rod Cell Outer Segment / Q000378:metabolism*
D005136:Eye Proteins; D008565:Membrane Proteins; D009599:Nitroprusside; D000246:Adenosine Diphosphate Ribose; D009569:Nitric Oxide; D019204:GTP-Binding Proteins