Skip to main content
PMC home page
The Journal of General Physiology logoLink to The Journal of General Physiology
. 1986 Nov 1;88(5):651–673. doi: 10.1085/jgp.88.5.651

Electrophysiological study of Drosophila rhodopsin mutants

PMCID: PMC2228850  PMID: 3097245

Abstract

Electrophysiological investigations were carried out on several independently isolated mutants of the ninaE gene, which encodes opsin in R1-6 photoreceptors, and a mutant of the ninaD gene, which is probably important in the formation of the rhodopsin chromophore. In these mutants, the rhodopsin content in R1-6 photoreceptors is reduced by 10(2)-10(6)-fold. Light-induced bumps recorded from even the most severely affected mutants are physiologically normal. Moreover, a detailed noise analysis shows that photoreceptor responses of both a ninaE mutant and a ninaD mutant follow the adapting bump model. Since any extensive rhodopsin-rhodopsin interactions are not likely in these mutants, the above results suggest that such interactions are not needed for the generation and adaptation of light-induced bumps. Mutant bumps are strikingly larger in amplitude than wild-type bumps. This difference is observed both in ninaD and ninaE mutants, which suggests that it is due to severe depletion of rhodopsin content, rather than to any specific alterations in the opsin protein. Lowering or buffering the intracellular calcium concentration by EGTA injection mimics the effects of the mutations on the bump amplitude, but, unlike the mutations, it also affects the latency and kinetics of light responses.

Full Text

The Full Text of this article is available as a PDF (1.3 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Baylor D. A., Lamb T. D., Yau K. W. The membrane current of single rod outer segments. J Physiol. 1979 Mar;288:589–611. [PMC free article] [PubMed] [Google Scholar]
  2. Brown H. M., Cornwall M. C. Spectral correlates of a quasi-stable depolarization in barnacle photoreceptor following red light. J Physiol. 1975 Jul;248(3):555–578. doi: 10.1113/jphysiol.1975.sp010988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Dodge F. A., Jr, Knight B. W., Toyoda J. Voltage noise in Limulus visual cells. Science. 1968 Apr 5;160(3823):88–90. doi: 10.1126/science.160.3823.88. [DOI] [PubMed] [Google Scholar]
  4. FUORTES M. G., YEANDLE S. PROBABILITY OF OCCURRENCE OF DISCRETE POTENTIAL WAVES IN THE EYE OF LIMULUS. J Gen Physiol. 1964 Jan;47:443–463. doi: 10.1085/jgp.47.3.443. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Harris W. A., Stark W. S., Walker J. A. Genetic dissection of the photoreceptor system in the compound eye of Drosophila melanogaster. J Physiol. 1976 Apr;256(2):415–439. doi: 10.1113/jphysiol.1976.sp011331. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Hillman P., Hochstein S., Minke B. A visual pigment with two physiologically active stable states. Science. 1972 Mar 31;175(4029):1486–1488. doi: 10.1126/science.175.4029.1486. [DOI] [PubMed] [Google Scholar]
  7. Lisman J. E., Bering H. Electrophysiological measurement of the number of rhodopsin molecules in single Limulus photoreceptors. J Gen Physiol. 1977 Nov;70(5):621–633. doi: 10.1085/jgp.70.5.621. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Lisman J. E., Brown J. E. Effects of intracellular injection of calcium buffers on light adaptation in Limulus ventral photoreceptors. J Gen Physiol. 1975 Oct;66(4):489–506. doi: 10.1085/jgp.66.4.489. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Martinez J. M., 2nd, Srebro R. Calcium and the control of discrete wave latency in the ventral photoreceptor of Limulus. J Physiol. 1976 Oct;261(3):535–562. doi: 10.1113/jphysiol.1976.sp011573. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Nolte J., Brown J. E., Smith T. G., Jr A hyperpolarizing component of the receptor potential in the median ocellus of Limulus. Science. 1968 Nov 8;162(3854):677–679. doi: 10.1126/science.162.3854.677. [DOI] [PubMed] [Google Scholar]
  11. O'Tousa J. E., Baehr W., Martin R. L., Hirsh J., Pak W. L., Applebury M. L. The Drosophila ninaE gene encodes an opsin. Cell. 1985 Apr;40(4):839–850. doi: 10.1016/0092-8674(85)90343-5. [DOI] [PubMed] [Google Scholar]
  12. Ostroy S. E. Characteristics of Drosophila rhodopsin in wild-type and norpA vision transduction mutants. J Gen Physiol. 1978 Nov;72(5):717–732. doi: 10.1085/jgp.72.5.717. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Pak W. L., Conrad S. K., Kremer N. E., Larrivee D. C., Schinz R. H., Wong F. Photoreceptor function. Basic Life Sci. 1980;16:331–346. doi: 10.1007/978-1-4684-7968-3_24. [DOI] [PubMed] [Google Scholar]
  14. RALL W. Membrane potential transients and membrane time constant of motoneurons. Exp Neurol. 1960 Oct;2:503–532. doi: 10.1016/0014-4886(60)90029-7. [DOI] [PubMed] [Google Scholar]
  15. Scavarda N. J., O'tousa J., Pak W. L. Drosophila locus with gene-dosage effects on rhodopsin. Proc Natl Acad Sci U S A. 1983 Jul;80(14):4441–4445. doi: 10.1073/pnas.80.14.4441. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Schinz R. H., Lo M. V., Larrivee D. C., Pak W. L. Freeze-fracture study of the Drosophila photoreceptor membrane: mutations affecting membrane particle density. J Cell Biol. 1982 Jun;93(3):961–967. doi: 10.1083/jcb.93.3.961. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Schwemer J., Henning U. Morphological correlates of visual pigment turnover in photoreceptors of the fly, Calliphora erythrocephala. Cell Tissue Res. 1984;236(2):293–303. doi: 10.1007/BF00214230. [DOI] [PubMed] [Google Scholar]
  18. Stephenson R. S., O'Tousa J., Scavarda N. J., Randall L. L., Pak W. L. Drosophila mutants with reduced rhodopsin content. Symp Soc Exp Biol. 1983;36:477–501. [PubMed] [Google Scholar]
  19. Steward R., Nüsslein-Volhard C. The genetics of the dorsal-Bicaudal-D region of Drosophila melanogaster. Genetics. 1986 Jul;113(3):665–678. doi: 10.1093/genetics/113.3.665. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Wong F., Knight B. W. Adapting-bump model for eccentric cells of Limulus. J Gen Physiol. 1980 Nov;76(5):539–557. doi: 10.1085/jgp.76.5.539. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Wong F., Knight B. W., Dodge F. A. Adapting bump model for ventral photoreceptors of Limulus. J Gen Physiol. 1982 Jun;79(6):1089–1113. doi: 10.1085/jgp.79.6.1089. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Wu C. F., Pak W. L. Light-induced voltage noise in the photoreceptor of Drosophila melanogaster. J Gen Physiol. 1978 Mar;71(3):249–268. doi: 10.1085/jgp.71.3.249. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Wu C. F., Pak W. L. Quantal basis of photoreceptor spectral sensitivity of Drosophila melanogaster. J Gen Physiol. 1975 Aug;66(2):149–168. doi: 10.1085/jgp.66.2.149. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Yeandle S., Spiegler J. B. Light-evoked and spontaneous discrete waves in the ventral nerve photoreceptor of Limulus. J Gen Physiol. 1973 May;61(5):552–571. doi: 10.1085/jgp.61.5.552. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Zuker C. S., Cowman A. F., Rubin G. M. Isolation and structure of a rhodopsin gene from D. melanogaster. Cell. 1985 Apr;40(4):851–858. doi: 10.1016/0092-8674(85)90344-7. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of General Physiology are provided here courtesy of The Rockefeller University Press

RESOURCES