Invertebrate visual transduction

There is a long history of studying invertebrate model preparations. Because of the large cells, the horshshoe crab Limulus was used to demonstrate how lateral inhibition enhances contrast detection. Nobel prize paper -- H. K. Hartline, Visual receptors and retinal interaction, Science 164, 270- 278, 1969

(empahsis on Drosophila)

unlike vertebrate, photoreceptors depolarize in response to light, not cGMP PDE, but PLC
Review phosphoinositide cascade: PIP2 -> IP3 & DAG
S. Kim, Analysis of norpA encoded multiple subtypes of phospholipase C in Drosophila melanogaster, 1997, Ph.D. Dissertation, SUNY Buffalo
TRANSPARENCY PI -> PIP -> PIP2 -> IP3 + DG
IP3 -> IP2 ->IP
DG -> PA [ATP donates phosphate](phosphatidic acid) -> CDP-DG (citidine diphosphate diacylglycerol)
TRRANSPARENCY - a comparison of how a neurotransmitter would activate PLC beta (already covered) vs. how a growth factor (with its tyrosine kinase) would act through PLC gamma
TRANSPARENCY the domain structures of PLC's:
beta-1 ia 1215 amino acids, has X and Y (conserved) domains
gamma has SH (src homology) domains between X and Y, 1289 amino acids
delta1 is 756 amino acids

PICTURE (from the research portion of my web site) ommatidia (about 800/compound eye) with R1-6, R7 and R8, plus 3 simple eyes (ocelli)
photoreceptive organelle is called rhabdomere
"genetic dissection"field started in late '60's with screens for mutants by (mostly) Benzer and Pak
genetic diisection or retina : work by Harris Stark and Walker, 1976, J. Physiol., 256, 415-439:
PICTURE (from the research portion of my web site) R1-6 is sensitive to blue and UV, R7 to UV and R8 to blue-green
ninaE gene for R1-6 rhodposin, Rh1
(there are other opsins):
Rh2 (ocelli)
Rh3 & Rh4 (UV rhodopsins in R7) (work by Zuker -- Feiler et al., J. Neurosci., 12, 3862-3868, 1992)
Rh5 & Rh6 in R8 (work by Britt -- Chou et al., Neuron 17, 1101-1115, 1997, also Paulsen -- Huber et al., FEBS Lett. 406, 1997, 6-10)
TRANSPARENCY shows rhodopsin homologous to vertebrates, Figure is from:
W. L. Pak, Use of Drosophila mutants in vision research, Mol. Cells 6 117-124, 1996
"nina" stands for "neither inactivation nor afterpotential" (refers to ERG = electroretinogram)
ninaA is a photoreceptor - specific cyclophilin
pepitidyl-proline cis-trans isomerase
also chaperone

norpA = "no receptor potential"
shown to code for PLC
recent paper:
R.R.McKay, D.-M.-Chen, K.Miller, S.Kim, W.S.Stark,R.D.Shortridge, Phospholipase C rescues visual defect in norpA mutants of Drosophila melanogaster. J. Biol. Chem. 27013271-13276, 1995
attach norpA coding sequence to ninaE promoter,
put in P-element, insert gene into norpA mutant
recovery in:
western
activity
LM & EM immunocytochemistry
and ERG (electroretinogram)

TRANSPARENCY (that I drew) and TRANSPARENCY - Signal transduction cascade from
Zuker, C. S. The biology of vision in Drosophila. PNAS 93 571-576, 1996
talk about:
regeneration of PIP2
rdgA (retinal degeneration) in diacylglycerol kinase
rdgB is PI transfer protein
inaC (inactivation - no afterpotential) is eye-specific PKC
and others
TRP and TRPL (transient receptor potential [like]) channels
TRANSPARENCY shows comparison of vertebrate and invertebrate phototransduction cascades - from K. Scott & C. Zuker, Trends in Biochemical Sciences, 22, 350-354, 1997

To understand channels, TRANSPARENCY transduction scheme:
B. Minke & Z. Selinger, Inositol lipid pathway in fly photoreceptors: Excitation, calcium mobilization and retinal degeneration. In Prog. Retinal Res. vol 11, eds. N. N. Osborne & G. J. Chader, Oxford, Pergamon Press
microvilli vs submicrovillar cisternae

D. D. Friel, TRP: Its role in phototransduction and store-operated Ca2+ entry (minireview). Cell 85 617-619, 1996
1275 a.a. 6 membrane spans (=> 4/channel)
TRANSPARENCY store-operated channel = SOC

PDZ domains (already covered with respect to NMDA receptor - NOS interaction
INAD (ina = inactivation, no afterpotential) protein binds channel
The molecules of transduction are compartmentalized together in a transduceosome
TRANSPARENCY (from Kim thesis) Rhodopsin, trp, Cam, norpA, G-protein, inaC, PLC all nearby, and transduction is thus very fast
R. van Huizen et al., Two distantly positioned PDZ domains mediate multivalent INAD - phospholipase C interactions essential for G-protein-coupled signalling, EMBO Journal, 1998, in press
TRANSPARENCY (van Huizen) INAD has 5 PDZ domains, 2 binding PLC

References

D. D. Friel, TRP: Its role in phototransduction and store-operated Ca2+ entry (minireview). Cell 85 617-619, 1996

Harris, W.A., Stark, W.S. and Walker, J.A. Genetic dissection of the photoreceptor system in the compound eye of Drosophila melanogaster. Journal of Physiology, 1976, 256, 415-439.

H. K. Hartline, Visual receptors and retinal interaction, Science 164, 270- 278, 1969

S. Kim, Analysis of norpA encoded multiple subtypes of phospholipase C in Drosophila melanogaster, 1997, Ph.D. Dissertation, SUNY Buffalo
(this one is not on reserve)

McKay, R. R, Chen, D.-M., Miller, K., Kim, S., Stark, W. S., Shortridge,R. D. Phospholipase C rescues defect in norpA mutant of Drosophila melanogaster. Journal of Biological Chemistry, 1995, 270, 13271-13276. PubMed

B. Minke & Z. Selinger, Inositol lipid pathway in fly photoreceptors: Excitation, calcium mobilization and retinal degeneration. In Prog. Retinal Res. vol 11, eds. N. N. Osborne & G. J. Chader, Oxford, Pergamon Press

W. L. Pak, Use of Drosophila mutants in vision research, Mol. Cells 6 117-124, 1996

K. Scott & C. Zuker, Trends in Biochemical Sciences, 22, 350-354, 1997

van Huizen, R., Miller, K., Chen, D.-M., Li, Y., Lai, Z.-C., Raab, R.W., Stark, W. S., Shortridge, R. D., Li, M. Two distantly positioned PDZ domains mediate multivalent INAD-phospholipase C interactions essential for the G protein-coupled signalling. EMBO Journal, 1998, 17, 2285-2297. PubMed

Zuker, C. S. The biology of vision in Drosophila. PNAS 93 571-576, 1996

This page was last updated on December 19, 2000

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