Summary
We examined changes in guanosine triphosphatedependent signal transduction mechanisms in the retina from the early stages of the streptozotocin-diabetic rat, a model for Type 1 (insulin-dependent) diabetes mellitus. Guanosine triphosphate binding, guanosine triphosphatase activity, and binding of (azido) guanosine triphosphate decreased significantly in the retina as early as 2 weeks after the induction of diabetes. The ability of guanosine triphosphate to inhibit forskolin-stimulatable adenyl cyclase was also abolished. These data suggest functional deterioration of G-proteins, especially Gi, in diabetic retina. Further studies using retinal rod outer segments revealed deterioration in light-sensitive, guanosine triphosphate-dependent functions of transducin in diabetic rats. Pertussis toxin-catalysed ADP ribosylation of the α subunit of transducin, a heterotrimeric G-protein of rod outer segments, was also reduced in diabetes. No functional effects were seen in purified subunits of transducin subjected to non-enzymatic glycation in vitro. On the other hand, incubation of non-diabetic rod outer segments with (12-0-tetradeconyl) phorbol-13-acetate, a protein kinase C agonist, in the presence of magnesium and adenosine triphosphate resulted in the reduction of guanosine triphosphate-binding and hydrolysis, thus indicating that protein kinase C may be involved in the regulation of these activities. The significance of these observations in the early visual abnormalities associated with diabetes is discussed.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Gilman AG (1987) G Proteins: transducers of receptor-generated signals. Ann Rev Biochem 56: 615–649
Taylor CW (1990) The role of G-proteins in transmembrane signalling. Biochem J 272: 1–13
Robertson RP (1991) G-proteins and modulation of insulin secretion. Diabetes 40: 1–6
Yamazaki A, Tatsumi M, Torney DC, Bitensky MW (1987) The GTP-binding protein of rod outer segments. J Biol Chem 262: 9316–9323
Yamazaki A, Bitensky MW, Garcia-Sainz JA (1987) The GTP-binding protein of rod outer segments. (II) An essential role of Mg + in signal amplification. J Biol Chem 262: 9324–9331
Birnbaumer L, Abramowitz J, Brown AM (1990) Receptor-effector coupling of G-proteins. Biochim Biophys Acta 1031: 163–224
Birnbaumer L (1990) G proteins in signal transduction. Ann Rev Pharmacol Toxicol 30: 675–705
Burgoyne RD (1989) Small GTP-binding proteins. TIBS 14: 394–396
Udrisor D, Rodbell M (1990) Microsomal and cytosolic fractions of guinea pig hepatocytes contain 100 kilodalton GTP-binding proteins reactive with antisera against α subunits of stimulatory and inhibitory heterotrimeric GTP-binding proteins. Proc Natl Acad Sci USA 87: 6321–6325
Pennington SR (1987) G proteins and diabetes. Nature 327: 188–189
Gawler D, Milligan G, Spiegel AM, Unson CG, Houslay MD (1987) Abolition of the expression of inhibitory guanine nucleotide regulatory protein Gi activity in diabetes. Nature 327: 229–232
Green A, Johnson JL (1991) Evidence for impaired coupling of receptors to Gi protein in adipocytes from streptozotocin-induced diabetic rats. Diabetes 40: 88–94
Merimee TJ (1990) Diabetic retinopathy. N Engl J Med 322: 978–983
Hardy KJ, Lipton J, Scase MO, Foster DH, Scarpello JHB (1990) Colour vision abnormalities in insulin-dependent diabetic patients with little or no retinopathy. Diabetologia 33 [Suppl]: A 88 (Abstract)
Henson DB, North RV (1979) Dark adaptation in diabetes mellitus. Br J Ophthalmol 63: 539–541
Begg IS, Broome SJ, Schulzer M (1982) Photostress recovery time in type # 1 diabetics. ARVO Meetings 2: 68
Elsner AE, Burns SA, Lobes LA, Doft BH (1987) Cone pigment bleaching abnormalities in diabetics. Invest Ophthalmol Vis Sci 28: 718–724
Kowluru A, Kowluru R, Bitensky MW, Corwin EJ, Solomon SS, Johnson JD (1987) Suggested mechanism for the selective excretion of glycosylated albumin. J Exp Med 166: 1259–1279
Kowluru RA, Bitensky MW, Kowluru A, Dembo M, Keaton PA, Buican T (1989) Reversible sodium pump defect and swelling in the diabetic red cell: effects on filterability and implications for microcirculation. Proc Natl Acad Sci USA 86: 3327–3331
O'Brien PJ, Zatz M (1984) Acylation of bovine rhodopsin by [3H]palmitic acid. J Biol Chem 259: 5054–5057
Birnbaumer L, Codina J, Ribeiro-Neto F, Mattera R, Iyengar R (1987) Techniques in the study of transmembrane signal transduction regulating cAMP formation. In: Schrader WJ, O'Malley BW (eds) The laboratory methods. Manual for hormone action and molecular endocrinology. Houston Biological Association, Houston, pp 1–46
Yada Y, Okano Y, Nozawa Y (1990) Enhancement of GTP S binding activity by cAMP-dependent phosphorylation of a filament-like 250 kd membrane protein in human platelets. Biochem Biophys Res Commun 172: 256–261
Kowluru A, MacDonald MJ (1984) Protein phosphorylation in pancreatic islets: evidence for separate calcium and cAMP phosphorylation of two 57,000 Mr proteins. Biochem Biophys Res Commun 118: 797–804
Kowluru A, MacDonald MJ (1984) Glucose-induced, calcium mediated protein phosphorylation in intact pancreatic islets. Arch Biochem Biophys 231: 320–327
Laemmli UK (1970) Cleavage of structural proteins during assembly of the head of bacteriophage T4. Nature 227: 680–684
Bradford MM (1976) A rapid and sensitive method for the quantitation of microgram quantities of protein. Anal Biochem 72: 248–254
Yamazaki A, Tatsumi M, Bitensky MW (1988) Purification of rod outer segment GTP-binding protein subunits and cyclic GMP phosphodiesterase by single step column chromatography. Meth Enzymol 159: 702–710
Bitensky MW, Kowluru A, Kowluru R (1989) Non-enzymatic glycation and protein recognition. In: Baynes JW, Monnier VM (eds) The maillard reactions in aging, diabetes, and nutrition. Alan R. Liss, New York, pp 185–203
Kowluru RA, Heidorn DB, Edmondson SP et al. (1989) Glycation of calmodulin: chemistry and structural and functional consequences. Biochemistry 28: 2220–2228
Metzger H, Linder E (1981) Forskolin: a novel adenylate cyclase-activator. IRCS Med Sci 9: 99
Seamon KB, Daly JW (1982) Guanosine 5′ (β-imido) triphosphate inhibition of forskolin activated adenylate cyclase by putative inhibitory guanine nucleotide regulatory protein. J Biol Chem 259: 5054–5057
Brownlee M, Vlassara H, Cerami A (1984) Nonenzymatic glycosylation and the pathogenesis of diabetic complications. Ann Intern Med 101: 527–537
Kondo T, Muurakami K, Ohtsuka Y et al. (1987) Estimation and characterization of glycosylated carbonic anhydrase I in erythrocytes from patients with diabetes mellitus. Clin Chim Acta 166: 227–236
Ditzel J, Anderson H, Daugaard-Peters N (1975) Oxygen affinity of hemoglobin and red cell 2,3-diphosphoglycerate in childhood diabetes. Acta Pediatr Scand 64: 355–361
Taniguchi N, Kinoshita N, Arai K, Izuka S (1989) Inactivation of erythrocyte Cu-Zn superoxide dismutase through non-enzymatic glycosylation. In: Baynes JW, Monnier VM (eds) The maillard reactions in aging, diabetes, and nutrition. Alan R. Liss, New York, pp 185–203
Zick Y, Eisenberg RS, Pines M, Gierschik P, Spiegel AM (1986) Multiple phosphorylation of the α subunit of transducin by the insulin receptor kinase and protein kinase C. Proc Natl Acad Sci USA 83: 9294–9297
Eisenberg RS (1989) GTP-binding proteins as possible targets for protein kinase C action. TIBS 14: 355–357
Katada T, Gilman AG, Watanabe Y, Bauer S, Jacobs KH (1985) Protein kinase C phosphorylates the inhibitory guanine nucleotide binding regulatory component and apparently suppresses its function in hormonal inhibition of adenylate cyclase. Eur J Biochem 151: 431–437
Watanabe Y, Imaizumi T, Misaki N, Iwakura K, Yoshida H (1988) Effects of phosphorylation of inhibitory GTP-binding protein by cAMP dependent protein kinase on its ADP-ribosylation by pertussis toxin, islet activating protein. FEBS Lett 236: 372–374
Lee TS, Saltsman KA, Ohashi H, King GL (1989) Activation of protein kinase C by elevation of glucose concentration: proposal for a mechanism in the development of diabetic complications. Proc Natl Acad Sci USA 86: 5141–5145
Strassheim D, Milligan G, Houslay MD (1990) Diabetes abolishes the GTP-dependent, but not the receptor-dependent inhibitory guanine-nucleotide binding regulatory protein (Gi) on adipocyte adenylate cyclase activity. Biochem J 266: 521–526
Bastyr EJ, Stowe R, Green A, Vinik AI, Kadrofske MM (1990) GTP-binding proteins are altered in platelets of type 1 diabetic patients with decreased PLC activity. Diabetes 39 [Suppl]: 28 A (Abstract)
Kowluru R, Kowluru A, Yamazaki A (1991) Altered erythrocyte G-protein metabolism in diabetes. FASEB J 5: 3151A (Abstract)
Hadjiconstanitnou M, Qu Z-X, Moroi-Fetters SE, Neff NH (1988) Apparent loss of Gi protein activity in diabetic retina. Eur J Pharmacol 149: 193–194
Kowluru A, Kowluru R (1992) Phospholipid N-methylation in diabetic erythrocytes: effects on membrane Na + -K + ATPase activity. Cell Biochem Funct (In press)
Pierce GN, Kutryk MJB, Dhalla NS (1983) Alterations in Ca2+ binding by and composition of the cardiac sarcolemmal membrane in chronic diabetes. Proc Natl Acad Sci USA 80: 5412–5416
Griffiths SL, Houslay MD (1990) G-protein αsubunit mRNAs in diabetic tissues. Biochem Soc Trans 18: 475–476
Ohkubo S, Yamada E, Endo T, Itoh H, Hidaka H (1984) Vitamin A acid-induced activation of Ca+2 activated, phospholipid dependent protein kinase from rabbit retina. Biochem Biophys Res Commun 118: 460–466
Kapoor CL, O'Brien PJ, Chadder GJ (1987) Phorbol ester and light-induced endogenous phosphorylation of rat rod outer segment proteins. Exp Eye Res 45: 545–556
Kelleher DJ, Johnson GL (1985) Purification of protein kinase from bovine rod outer segments. J Cyclic Nucleotide Prot Phos Res 10: 579–591
Fowles C, Akhtar M, Cohen P (1989) Interplay of phosphorylation and dephosphorylation in vision: protein phosphatase of bovine rod outer segments. Biochemistry 28: 9385–9391
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Kowluru, A., Kowluru, R.A. & Yamazaki, A. Functional alterations of G-proteins in diabetic rat retina: a possible explanation for the early visual abnormalities in diabetes mellitus. Diabetologia 35, 624–631 (1992). https://doi.org/10.1007/BF00400253
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00400253