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Distinct contributions of rod, cone, and melanopsin photoreceptors to encoding irradiance.

Lall GS, Revell VL, Momiji H, Al Enezi J, Altimus CM, Güler AD, Aguilar C, Cameron MA, Allender S, Hankins MW, Lucas RJ - Neuron (2010)

Bottom Line: These photoreceptors define circadian responses at very dim "scotopic" light levels but also at irradiances at which pattern vision relies heavily on cones.By contrast, cone input to irradiance responses dissipates following light adaptation to the extent that these receptors make a very limited contribution to circadian and pupillary light responses under these conditions.Our data provide new insight into retinal circuitry upstream of mRGCs and optimal stimuli for eliciting irradiance responses.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Life Sciences, AV Hill Building, University of Manchester, Manchester M13 9PT, UK.

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Enhanced Long-Wavelength Sensitivity of Cone Vision in Opn1mwR Mice(A) In Opn1mwR mice, the native mouse m-cone opsin (dotted green line, shows spectral sensitivity approximated by opsin nomogram [Govardovskii et al., 2000] with peak sensitivity [λmax] = 511 nm) is lost and replaced with a human red cone opsin (Smallwood et al., 2003) whose spectral sensitivity (red line; λmax = 556 nm) profile is quite distinct from that of mouse rod (λmax = 498 nm), melanopsin (λmax = 480 nm), and s-cone (λmax = 360 nm) opsins (black, blue, and purple lines, respectively).(B) Divergence in the spectral sensitivity of red cones, rods, and melanopsin is reflected in large differences in their relative sensitivity to mid- (500 nm) and long- (600 or 650 nm) wavelength light.(C) Red cone input to the pupil light reflex is revealed as a significant increase in response to a 1 min, 650 nm stimulus (3 × 1014 photons/cm2/s) in Opn1mwR mice compared with wild-type mice (mean ± SEM; t test, p < 0.01). The genotypes showed similar responses to an equivalent (1 min; 3 × 1014 photons/cm2/s) 500 nm stimulus (mean ± SEM; n = 8–12; t test, p > 0.05).
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fig1: Enhanced Long-Wavelength Sensitivity of Cone Vision in Opn1mwR Mice(A) In Opn1mwR mice, the native mouse m-cone opsin (dotted green line, shows spectral sensitivity approximated by opsin nomogram [Govardovskii et al., 2000] with peak sensitivity [λmax] = 511 nm) is lost and replaced with a human red cone opsin (Smallwood et al., 2003) whose spectral sensitivity (red line; λmax = 556 nm) profile is quite distinct from that of mouse rod (λmax = 498 nm), melanopsin (λmax = 480 nm), and s-cone (λmax = 360 nm) opsins (black, blue, and purple lines, respectively).(B) Divergence in the spectral sensitivity of red cones, rods, and melanopsin is reflected in large differences in their relative sensitivity to mid- (500 nm) and long- (600 or 650 nm) wavelength light.(C) Red cone input to the pupil light reflex is revealed as a significant increase in response to a 1 min, 650 nm stimulus (3 × 1014 photons/cm2/s) in Opn1mwR mice compared with wild-type mice (mean ± SEM; t test, p < 0.01). The genotypes showed similar responses to an equivalent (1 min; 3 × 1014 photons/cm2/s) 500 nm stimulus (mean ± SEM; n = 8–12; t test, p > 0.05).

Mentions: The red cone knockin allele (referred to here as Opn1mwR) results in a substantial, long-wavelength shift in the spectral sensitivity of those cones that would ordinarily express m-cone opsin (Figure 1; Smallwood et al., 2003). Electrophysiological and behavioral assessments suggest that these red cones retain normal function and retinal connectivity (Jacobs et al., 2007; Smallwood et al., 2003). To determine whether they are capable of driving NIF responses, we first compared pupillary responses to bright medium- (500 nm) and long-wavelength (650 nm) stimuli in Opn1mwR males with those of littermate wild-type mice. As expected, the two genotypes had equivalent responses to 500 nm (Figure 1C). However, 650 nm induced much larger constriction in Opn1mwR animals (Figure 1C), suggesting involvement of cones in this response.


Distinct contributions of rod, cone, and melanopsin photoreceptors to encoding irradiance.

Lall GS, Revell VL, Momiji H, Al Enezi J, Altimus CM, Güler AD, Aguilar C, Cameron MA, Allender S, Hankins MW, Lucas RJ - Neuron (2010)

Enhanced Long-Wavelength Sensitivity of Cone Vision in Opn1mwR Mice(A) In Opn1mwR mice, the native mouse m-cone opsin (dotted green line, shows spectral sensitivity approximated by opsin nomogram [Govardovskii et al., 2000] with peak sensitivity [λmax] = 511 nm) is lost and replaced with a human red cone opsin (Smallwood et al., 2003) whose spectral sensitivity (red line; λmax = 556 nm) profile is quite distinct from that of mouse rod (λmax = 498 nm), melanopsin (λmax = 480 nm), and s-cone (λmax = 360 nm) opsins (black, blue, and purple lines, respectively).(B) Divergence in the spectral sensitivity of red cones, rods, and melanopsin is reflected in large differences in their relative sensitivity to mid- (500 nm) and long- (600 or 650 nm) wavelength light.(C) Red cone input to the pupil light reflex is revealed as a significant increase in response to a 1 min, 650 nm stimulus (3 × 1014 photons/cm2/s) in Opn1mwR mice compared with wild-type mice (mean ± SEM; t test, p < 0.01). The genotypes showed similar responses to an equivalent (1 min; 3 × 1014 photons/cm2/s) 500 nm stimulus (mean ± SEM; n = 8–12; t test, p > 0.05).
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fig1: Enhanced Long-Wavelength Sensitivity of Cone Vision in Opn1mwR Mice(A) In Opn1mwR mice, the native mouse m-cone opsin (dotted green line, shows spectral sensitivity approximated by opsin nomogram [Govardovskii et al., 2000] with peak sensitivity [λmax] = 511 nm) is lost and replaced with a human red cone opsin (Smallwood et al., 2003) whose spectral sensitivity (red line; λmax = 556 nm) profile is quite distinct from that of mouse rod (λmax = 498 nm), melanopsin (λmax = 480 nm), and s-cone (λmax = 360 nm) opsins (black, blue, and purple lines, respectively).(B) Divergence in the spectral sensitivity of red cones, rods, and melanopsin is reflected in large differences in their relative sensitivity to mid- (500 nm) and long- (600 or 650 nm) wavelength light.(C) Red cone input to the pupil light reflex is revealed as a significant increase in response to a 1 min, 650 nm stimulus (3 × 1014 photons/cm2/s) in Opn1mwR mice compared with wild-type mice (mean ± SEM; t test, p < 0.01). The genotypes showed similar responses to an equivalent (1 min; 3 × 1014 photons/cm2/s) 500 nm stimulus (mean ± SEM; n = 8–12; t test, p > 0.05).
Mentions: The red cone knockin allele (referred to here as Opn1mwR) results in a substantial, long-wavelength shift in the spectral sensitivity of those cones that would ordinarily express m-cone opsin (Figure 1; Smallwood et al., 2003). Electrophysiological and behavioral assessments suggest that these red cones retain normal function and retinal connectivity (Jacobs et al., 2007; Smallwood et al., 2003). To determine whether they are capable of driving NIF responses, we first compared pupillary responses to bright medium- (500 nm) and long-wavelength (650 nm) stimuli in Opn1mwR males with those of littermate wild-type mice. As expected, the two genotypes had equivalent responses to 500 nm (Figure 1C). However, 650 nm induced much larger constriction in Opn1mwR animals (Figure 1C), suggesting involvement of cones in this response.

Bottom Line: These photoreceptors define circadian responses at very dim "scotopic" light levels but also at irradiances at which pattern vision relies heavily on cones.By contrast, cone input to irradiance responses dissipates following light adaptation to the extent that these receptors make a very limited contribution to circadian and pupillary light responses under these conditions.Our data provide new insight into retinal circuitry upstream of mRGCs and optimal stimuli for eliciting irradiance responses.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Life Sciences, AV Hill Building, University of Manchester, Manchester M13 9PT, UK.

Show MeSH
Related in: MedlinePlus