Abstract
The cationic conductances of purified bovine retinal rod membranes were studied by incorporation of vesicles into planar lipid bilayers. When the membranes were stripped of all peripheral proteins [guanine nucleotide-binding protein (G protein) and cGMP phosphodiesterase (3',5'-cyclic-GMP 5'-nucleotidohydrolase), EC 3.1.4.35], sodium and calcium fluxes were almost only observed in the presence of cGMP. Reconstitution experiments in which purified cGMP phosphodiesterase alone or with G protein were reassociated to the vesicles in proportions similar to those found in the native rod provide evidence for a direct interaction between the cGMP-dependent channel protein and the phosphodiesterase. (i) In its inhibited state, phosphodiesterase markedly stimulates the activity of the channels in the presence of cGMP (situation in the dark-adapted rod) but is not capable of activating the channels in the absence of cGMP. (ii) In the absence of cGMP, activation of the phosphodiesterase by G protein with GTP bound (equivalent to photoexcitation) induces the opening of cation channels that have the same conductance for sodium ions as cGMP-activated channels (20-22 pS, with two sublevels of about 7 pS and 13 pS).
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- Baehr W., Devlin M. J., Applebury M. L. Isolation and characterization of cGMP phosphodiesterase from bovine rod outer segments. J Biol Chem. 1979 Nov 25;254(22):11669–11677. [PubMed] [Google Scholar]
- Baehr W., Morita E. A., Swanson R. J., Applebury M. L. Characterization of bovine rod outer segment G-protein. J Biol Chem. 1982 Jun 10;257(11):6452–6460. [PubMed] [Google Scholar]
- Bauer P. J. Evidence for two functionally different membrane fractions in bovine retinal rod outer segments. J Physiol. 1988 Jul;401:309–327. doi: 10.1113/jphysiol.1988.sp017164. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bennett N. A functional link between the dark Mg-ATPase activity and the light-induced enzymatic cascade in rod outer segments. Eur J Biochem. 1986 Jun 16;157(3):487–495. doi: 10.1111/j.1432-1033.1986.tb09693.x. [DOI] [PubMed] [Google Scholar]
- Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1016/0003-2697(76)90527-3. [DOI] [PubMed] [Google Scholar]
- Brown A. M., Birnbaumer L. Direct G protein gating of ion channels. Am J Physiol. 1988 Mar;254(3 Pt 2):H401–H410. doi: 10.1152/ajpheart.1988.254.3.H401. [DOI] [PubMed] [Google Scholar]
- Caretta A., Cavaggioni A. Fast ionic flux activated by cyclic GMP in the membrane of cattle rod outer segments. Eur J Biochem. 1983 Apr 15;132(1):1–8. doi: 10.1111/j.1432-1033.1983.tb07317.x. [DOI] [PubMed] [Google Scholar]
- Cook N. J., Hanke W., Kaupp U. B. Identification, purification, and functional reconstitution of the cyclic GMP-dependent channel from rod photoreceptors. Proc Natl Acad Sci U S A. 1987 Jan;84(2):585–589. doi: 10.1073/pnas.84.2.585. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fesenko E. E., Kolesnikov S. S., Lyubarsky A. L. Induction by cyclic GMP of cationic conductance in plasma membrane of retinal rod outer segment. Nature. 1985 Jan 24;313(6000):310–313. doi: 10.1038/313310a0. [DOI] [PubMed] [Google Scholar]
- Hanke W., Cook N. J., Kaupp U. B. cGMP-dependent channel protein from photoreceptor membranes: single-channel activity of the purified and reconstituted protein. Proc Natl Acad Sci U S A. 1988 Jan;85(1):94–98. doi: 10.1073/pnas.85.1.94. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Haynes L. W., Kay A. R., Yau K. W. Single cyclic GMP-activated channel activity in excised patches of rod outer segment membrane. Nature. 1986 May 1;321(6065):66–70. doi: 10.1038/321066a0. [DOI] [PubMed] [Google Scholar]
- Koch K. W., Kaupp U. B. Cyclic GMP directly regulates a cation conductance in membranes of bovine rods by a cooperative mechanism. J Biol Chem. 1985 Jun 10;260(11):6788–6800. [PubMed] [Google Scholar]
- Koch K. W., Stryer L. Highly cooperative feedback control of retinal rod guanylate cyclase by calcium ions. Nature. 1988 Jul 7;334(6177):64–66. doi: 10.1038/334064a0. [DOI] [PubMed] [Google Scholar]
- Kondo H., Miller W. H. Rod light adaptation may be mediated by acceleration of the phosphodiesterase-guanylate cyclase cycle. Proc Natl Acad Sci U S A. 1988 Feb;85(4):1322–1326. doi: 10.1073/pnas.85.4.1322. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
- Liebman P. A., Evanczuk A. T. Real time assay of rod disk membrane cGMP phosphodiesterase and its controller enzymes. Methods Enzymol. 1982;81:532–542. doi: 10.1016/s0076-6879(82)81074-4. [DOI] [PubMed] [Google Scholar]
- Matesic D., Liebman P. A. cGMP-dependent cation channel of retinal rod outer segments. Nature. 1987 Apr 9;326(6113):600–603. doi: 10.1038/326600a0. [DOI] [PubMed] [Google Scholar]
- Matthews G. Single-channel recordings demonstrate that cGMP opens the light-sensitive ion channel of the rod photoreceptor. Proc Natl Acad Sci U S A. 1987 Jan;84(1):299–302. doi: 10.1073/pnas.84.1.299. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Matthews H. R., Murphy R. L., Fain G. L., Lamb T. D. Photoreceptor light adaptation is mediated by cytoplasmic calcium concentration. Nature. 1988 Jul 7;334(6177):67–69. doi: 10.1038/334067a0. [DOI] [PubMed] [Google Scholar]
- Nakatani K., Yau K. W. Calcium and light adaptation in retinal rods and cones. Nature. 1988 Jul 7;334(6177):69–71. doi: 10.1038/334069a0. [DOI] [PubMed] [Google Scholar]
- Pearce L. B., Calhoon R. D., Burns P. R., Vincent A., Goldin S. M. Two functionally distinct forms of guanosine cyclic 3',5'-phosphate stimulated cation channels in a bovine rod photoreceptor disk preparation. Biochemistry. 1988 Jun 14;27(12):4396–4406. doi: 10.1021/bi00412a029. [DOI] [PubMed] [Google Scholar]
- Pepe I. M., Panfoli I., Cugnoli C. Guanylate cyclase in rod outer segments of the toad retina. Effect of light and Ca2+. FEBS Lett. 1986 Jul 14;203(1):73–76. doi: 10.1016/0014-5793(86)81439-9. [DOI] [PubMed] [Google Scholar]
- Puckett K. L., Goldin S. M. Guanosine 3',5'-cyclic monophosphate stimulates release of actively accumulated calcium in purified disks from rod outer segments of bovine retina. Biochemistry. 1986 Apr 8;25(7):1739–1746. doi: 10.1021/bi00355a044. [DOI] [PubMed] [Google Scholar]
- Pugh E. N., Jr, Cobbs W. H. Visual transduction in vertebrate rods and cones: a tale of two transmitters, calcium and cyclic GMP. Vision Res. 1986;26(10):1613–1643. doi: 10.1016/0042-6989(86)90051-9. [DOI] [PubMed] [Google Scholar]
- Schnetkamp P. P., Bownds M. D. Na+- and cGMP-induced Ca2+ fluxes in frog rod photoreceptors. J Gen Physiol. 1987 Mar;89(3):481–500. doi: 10.1085/jgp.89.3.481. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stern J. H., Kaupp U. B., MacLeish P. R. Control of the light-regulated current in rod photoreceptors by cyclic GMP, calcium, and l-cis-diltiazem. Proc Natl Acad Sci U S A. 1986 Feb;83(4):1163–1167. doi: 10.1073/pnas.83.4.1163. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tanaka J. C., Furman R. E., Cobbs W. H., Mueller P. Incorporation of a retinal rod cGMP-dependent conductance into planar bilayers. Proc Natl Acad Sci U S A. 1987 Feb;84(3):724–728. doi: 10.1073/pnas.84.3.724. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Torre V., Matthews H. R., Lamb T. D. Role of calcium in regulating the cyclic GMP cascade of phototransduction in retinal rods. Proc Natl Acad Sci U S A. 1986 Sep;83(18):7109–7113. doi: 10.1073/pnas.83.18.7109. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Uhl R., Borys T., Abrahamson E. W. Evidence for structural changes in the photoreceptor disk membrane, enabled by magnesium ATPase activity and triggered by light. FEBS Lett. 1979 Nov 15;107(2):317–322. doi: 10.1016/0014-5793(79)80398-1. [DOI] [PubMed] [Google Scholar]
- Yamazaki A., Bartucca F., Ting A., Bitensky M. W. Reciprocal effects of an inhibitory factor on catalytic activity and noncatalytic cGMP binding sites of rod phosphodiesterase. Proc Natl Acad Sci U S A. 1982 Jun;79(12):3702–3706. doi: 10.1073/pnas.79.12.3702. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yau K. W., Nakatani K. Light-induced reduction of cytoplasmic free calcium in retinal rod outer segment. Nature. 1985 Feb 14;313(6003):579–582. doi: 10.1038/313579a0. [DOI] [PubMed] [Google Scholar]
- Zimmerman A. L., Baylor D. A. Cyclic GMP-sensitive conductance of retinal rods consists of aqueous pores. Nature. 1986 May 1;321(6065):70–72. doi: 10.1038/321070a0. [DOI] [PubMed] [Google Scholar]
- Zimmerman A. L., Yamanaka G., Eckstein F., Baylor D. A., Stryer L. Interaction of hydrolysis-resistant analogs of cyclic GMP with the phosphodiesterase and light-sensitive channel of retinal rod outer segments. Proc Natl Acad Sci U S A. 1985 Dec;82(24):8813–8817. doi: 10.1073/pnas.82.24.8813. [DOI] [PMC free article] [PubMed] [Google Scholar]

