Biophysics of structure and mechanism

, Volume 9, Issue 3, pp 171–180 | Cite as

Ultraviolet sensitivity of fly photoreceptors R7 and R8: Evidence for a sensitising function

  • R. C. Hardie
  • K. Kirschfeld


Responses to continuous spectral scans in the ultraviolet (uv) have been measured intracellularly from the central retinula cells R7 and R8 in the fly (Musca, female). The spectral sensitivities thus obtained have a resolution limited by the bandwidth of the light supplied by the mono-chromator (0.3–1.5 nm).

One class of R7 cells, classified as 7y (Kirschfeld et al. 1978) shows three conspicuous peaks of sensitivity at 337, 355 and 373 nm (Fig. 3a). The underlying R8 cells (8y) also show three peaks but at slightly shorter wavelengths — 334, 350, and 369 nm (Fig. 3c), coinciding with those seen in the peripheral photoreceptors R1–6 (Gemperlein et al. 1980; Kirschfeld et al. 1982). Another class of R7 cells (7p) showed a spectral sensitivity function with a single peak at 330 nm. The underlying R8 cells (8p) also show a single-peaked function with maximum at 460 nm (Fig. 3b and d).

The results are interpreted as providing evidence for the hypothesis that uv sensitivity in 7y and 8y cells is conferred by a uv absorbing sensitising pigment similar to that demonstrated in R1-6 cells. The spectra of both 7p and 8p cells can be simply interpreted as deriving directly from the absorption of a rhodopsin with the appropriate λ max.

Key words

Musca-photoreceptors R7 and R8 uv sensitivity Sensitising pigment 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Förster T (1951) Fluoreszenz organischer Verbindungen. Vandenhoeck und Ruprecht, GöttingenGoogle Scholar
  2. Franceschini N (1983) In vivo microspectrofluorimetry of visual pigments. In: Cosens D (ed) Biology of photoreceptors. Cambridge University Press, CambridgeGoogle Scholar
  3. Franceschini N, Kirschfeld K, Minke B (1981a) Fluorescence of photoreceptor cells observed in vivo. Science 213: 1264–1267Google Scholar
  4. Franceschini N, Hardie RC, Ribi W, Kirschfeld K (1981b) Sexual dimorphism in a photoreceptors. Nature 291: 241–244Google Scholar
  5. Fugate RD, Song P (1980) Spectroscopic characterisation of Β-lactoglobulin-retinol complex. Biochim Biophys Acta 625: 28–42Google Scholar
  6. Gemperlein R, Paul R, Lindauer E, Steiner A (1980) UV fine structure of the spectral sensitivity of flies visual cells. Naturwiss 67: 565–566Google Scholar
  7. Hamdorf K (1979) The physiology of invertebrate visual pigments. In: Autrum H (ed) Handbook of sensory physiology VII/6A. Springer, Berlin Heidelberg New YorkGoogle Scholar
  8. Hardie RC (1978) Peripheral visual function in the fly. Thesis, CanberraGoogle Scholar
  9. Hardie RC (1979) Electrophysiological analysis of the fly retina. I. Comparative properties of R1-6 and R7 and 8. J Cornp Physiol 129: 19–33Google Scholar
  10. Hardie RC, Franceschini N, McIntyre PD (1979) Electrophysiological analysis of the fly retina. II. Spectral and polarisation sensitivity in R7 and R8. J Comp Physiol 133: 23–29Google Scholar
  11. Hardie RC, Franceschini N, Ribi W, Kirschfeld K (1981) Distribution and properties of sex-specific photoreceptors in the fly Musca domestica. J Comp Physiol 145: 139–152Google Scholar
  12. Hemley R, Kohler BE, Siviski P (1979) Absorption spectra for the complexes formed from vitamin A and Β-lactoglobulin. Biophys J 28: 447–455Google Scholar
  13. Kirschfeld K (1979) The function of photostable pigments in fly photoreceptors. Biophys Struct Mech 5: 117–128Google Scholar
  14. Kirschfeld K, Franceschini N, Minke B (1977) Evidence for a sensitising pigment in fly photoreceptors. Nature 269: 386–390Google Scholar
  15. Kirschfeld K, Feiler R, Franceschini N (1978) A photostable pigment within the rhabdomere of fly photoreceptors no 7. J Comp Physiol 125: 275–284Google Scholar
  16. Kirschfeld K, Feiler R, Franceschini N, Hardie RC, Vogt K (1983) Sensitising pigment in fly photoreceptors: properties and candidates. Biophys Struct Mech 9 (in press)Google Scholar
  17. Kuo A (1980) Elektrophysiologische Untersuchungen zur Spektral- und Polarisationsempfindlichkeit der Sehzellen von Calliphiora erythrocephala I. Sci Sin 23: 1182–1196Google Scholar
  18. Kuo A (1981a) ibid.. Sci Sin 24: 272–286Google Scholar
  19. Kuo A (1981b) ibid.. Sci Sin 24: 542–553Google Scholar
  20. McIntyre PD, Kirschfeld K (1981) Absorption properties of a photostable pigment (P 456) in rhabdomere 7 of the fly. J Comp Physiol 143: 3–15Google Scholar
  21. Minke B, Kirschfeld K (1979) The contribution of the sensitising pigment to the photosensitivity spectra of fly rhodopsin and metarhodopsin. J Gen Physiol 73: 517–540Google Scholar
  22. Smola U, Meffert P (1979) The spectral sensitivity of the visual cells R7 and R8 in the eye of the blowfly Calliphora erythrocephala. J Comp Physiol 133: 41–52Google Scholar
  23. Stark WS, Ivanyshyn AM, Greenberg RM (1977) Sensitivity and photopigments of R1-6, a two-peaked photoreceptor in Drosophila, Calliphora and Musca. J Comp Physiol 121: 289–305Google Scholar
  24. Vogt K, Kirschfeld K (1983) Sensitising pigment in the fly. Biophys Struct Mech 9 (in press)Google Scholar

Copyright information

© Springer-Verlag 1983

Authors and Affiliations

  • R. C. Hardie
    • 1
  • K. Kirschfeld
    • 1
  1. 1.Max-Planck-Institut für biologische KybernetikTübingenGermany

Personalised recommendations