A New Receptor Potential of the Monkey Retina with no Detectable Latency

Brown, Kenneth T.; Murakami, Motohiko

doi:10.1038/201626a0

Cited by 239 publications

(75 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Microspectrophotometry (25)(26)(27). The amplitude of the M1 potential is thus linearly proportional to the amount of metarhodopsin5w in R1-6 photoreceptors activated by the light stimulus.…”

Section: Methodsmentioning

confidence: 99%

Drosophila locus with gene-dosage effects on rhodopsin

Scavarda

O'Tousa

Pak

1983

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Mutations that decrease the amplitude of the prolonged depolarizing afterpotential (PDA) in Drosophila melanogaster have been shown to have reduced rhodopsin content in the rhabdomeres of photoreceptor cells. In the present study, a genetic analysis of a class of third chromosome PDA-defective mutants localized the ninaE locus to the salivary band region 92A-B. In flies with only one copy of this region instead of the normal two copies, and in ninaE heterozygotes, the rhodopsin content of the major class of photoreceptors is reduced. Three doses of this region increase the rhodopsin content of these photoreceptors. There are three anatomical classes of photoreceptors in the Drosophila compound eve. The six peripheral photoreceptors (R1-6) all contain the same rhodopsin, which maximally absorbs at 480 nm (rhodopsin480), and photointerconverts with a thermostable metarhodopsin that absorbs maximally at 580 nm (metarhodopsin.%O) (2)(3)(4). This is the most abundant species of rhodopsin in the Drosophila eve. The other two classes of photoreceptors, R7 and R8, contain visual pigments that are spectrallv distinct from R1-6 rhodopsin (4)(5)(6).Mutations that reduce the amount of R1-6 rhodopsin were isolated by taking advantage of the prolonged depolarizing afterpotential (PDA). The PDA, which has been elicited from a wide variety of invertebrate photoreceptors studied (7-13), results from a net photoconversion of a substantial quantity (>20%) of rhodopsin to metarhodopsin. In the ERG of Drosophila, the R1-6 PDA is observed as a sustained corneal-negative potential that persists long after the termination of the PDA-inducing blue light stimulus (see Fig. la). During a fully developed PDA, the R1-6 photoreceptors are inactivated and do not respond to an additional blue light stimulus. The small, superimposed reThe publication costs of this article were defrayed in part by page charge payment. This article must therefore be herebv marked "advertisement" in accordance with 18 U.S.C. § 1734 solely to indicate this fact. (14). These genes are designated nina (neither inactivation nor afterpotential).The structural gene of a protein may be identified by examining the effect of varying the dosage of the gene on the amount of protein product synthesized (15). Because two copies of a gene are normally present, a flv with only one copy of a gene will have decreased levels of gene product, and a fly with three copies will have increased levels of gene product. In Drosophila this effect has been observed for the gene products of all known structural genes that have been assaved to date (15). In addition, genes that are thought to be of a regulatory nature in Drosophila have never been shown to exhibit dosage effects on the product of a second gene for both increased and decreased gene dosage. In this report we show that one of the nina loci, ninaE, has genetic properties expected of the R1-6 opsin structural gene. MATERIALS AND METHODSMutant Characterization. The ninaE mutants were recovered as described by Pak (16). The...

show abstract

Section: Methodsmentioning

confidence: 99%

Drosophila locus with gene-dosage effects on rhodopsin

Scavarda

O'Tousa

Pak

1983

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…It has also been shown that the chromophore is linked covalently to the lipoprotein (3,4), and that it may possibly undergo a change in covalent bonding (5). The mechanism by which the nerve impulse is initiated is still obscure; an early receptor potential accompanying retinal illumination has been observed (6); it may be related to isomerization or to the transfer (5) of the chromophore, but it is not clear whether this potential is part of the mechanism of excitation. 8…”

mentioning

confidence: 99%

Structures of the Visual Chromophores and Related Pigments: A Conformational Basis of Visual Excitation

Sundaralingam

Beddell

1972

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

“…Then a 'positive' photoresponse develops and the membrane potential reaches its maximum in the ms time scale. Both the kinetics and the direction of the electric vector prove similar to the early receptor potential that is also composed of oppositely-directed phases, Rl and R2 [21]. Computer analysis of the above data revealed the existence of at least two exponents in the 'positive' photoresponse, the r-values of the more rapid electrogenic phase being 50 PS for bacterial and 500 ps for animal rhodopsins.…”

Section: Methodsmentioning

confidence: 82%