Ancestral photoreceptor diversity as the basis of visual behaviour

Nature Ecology & Evolution, Journal Year: 2024, Volume and Issue: 8(3), P. 374 - 386

Published: Jan. 22, 2024

Language: Английский

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Morphology and connectivity of retinal horizontal cells in two avian species

Frontiers in Cellular Neuroscience, Journal Year: 2025, Volume and Issue: 19

Published: March 4, 2025

In the outer vertebrate retina, visual signal is separated into intensity and wavelength information. birds, seven types of photoreceptors (one rod, four single cones, two members double cone) mediate signals to >20 second-order neurons, bipolar cells horizontal cells. Horizontal contribute color contrast processing by providing feedback feedforward fish, reptiles, amphibians they either encode or show color-opponent responses. Yet, for bird number cell not fully resolved even more importantly, synapses between have never been quantified any species. With a combination light microscopy serial EM reconstructions, we found different in distantly related species, domestic chicken European robin. agreement with some earlier studies, confirmed highly abundant (H1, H2) rare (H3, H4), which H1 an axon-bearing cell, whereas H2-H4 are axonless. made chemical one type interplexiform amacrine at their soma. Dendritic contacts H1-H4 were type-specific similar turtle confirms high degree evolutionary conservation retina. Our data further suggests that potentially H2 may intensity, H3 H4 represent opponent birds’ superb and/or acuity vision.

Language: Английский

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From water to land: Evolution of photoreceptor circuits for vision in air

PLoS Biology, Journal Year: 2024, Volume and Issue: 22(1), P. e3002422 - e3002422

Published: Jan. 22, 2024

When vertebrates first conquered the land, they encountered a visual world that was radically distinct from of their aquatic ancestors. Fish exploit strong wavelength-dependent interactions light with water by differentially feeding signals up to 5 spectral photoreceptor types into behavioural programmes. However, above same rules do not apply, and this called for an update circuit strategies. Early tetrapods soon evolved double cone, still poorly understood pair new photoreceptors brought “ancestral terrestrial” complement 7. Subsequent nonmammalian lineages adapted highly parallelised retinal input strategy diverse ecologies. By contrast, mammals shed most ancestral converged on is exceptionally general. In eutherian including in humans, parallelisation emerges gradually as signal traverses layers retina brain.

Language: Английский

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Ancient origin of the rod bipolar cell pathway in the vertebrate retina

Nature Ecology & Evolution, Journal Year: 2024, Volume and Issue: 8(6), P. 1165 - 1179

Published: April 16, 2024

Language: Английский

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Species–specific circuitry of double cone photoreceptors in two avian retinas

Communications Biology, Journal Year: 2024, Volume and Issue: 7(1)

Published: Aug. 14, 2024

Abstract In most avian retinas, double cones (consisting of a principal and accessory member) outnumber other photoreceptor types have been associated with various functions, such as encoding luminance, sensing polarized light, magnetoreception. However, their down-stream circuitry is poorly understood, particularly across bird species. Analysing species differences important to understand changes in driven by ecological adaptations. We compare the ultrastructure postsynaptic bipolar cells between night-migratory European robin non-migratory chicken. discover four previously unidentified cell retina, including midget-like mainly connected one member. A downstream ganglion reveals complete circuit similar peripheral primate retina. Additionally, we identify selective transmitting information from specific subset members. Our data highlight species-specific cone connectivity, potentially reflecting

Language: Английский

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Single cones give rise to multi-cone types in the retinas of fishes

Scientific Reports, Journal Year: 2025, Volume and Issue: 15(1)

Published: March 6, 2025

Retinal cone photoreceptors are specialized neurons that capture light to begin the process of daylight vision. They occur as individual cells (i.e., single cones), or combinations structurally linked cells, such double and triple cones found in retinas non-eutherian vertebrates. These different morphological types form mosaics varying regularity, with patterned nearly perfect lattices many bony fishes (teleosts) some geckos. Although were first reported over 150 years ago, how they whether from coalescing cones, progenitors) remains uncertain. In turn, there is a general vertebrate sequence appearance unknown. Here, developing seven species teleosts examined revealing only arranged hexagonal-like mosaics, present at earliest stages photoreceptor differentiation. Double arose formation multi-cone type (such square mosaic, where each surrounded by four cones) followed dynamics depending on was altricial precocial. Single therefore primordial which all preceded other mosaic patterns. Based observations transitional retinas, we propose model for transformation hexagonal square. The those land vertebrates constitute an example convergent evolution achieve elliptical waveguide structure, likely improved spatio-temporal resolution.

Language: Английский

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Comparative transcriptomic insights into the evolution of vertebrate photoreceptor types

Current Biology, Journal Year: 2025, Volume and Issue: unknown

Published: April 1, 2025

Language: Английский

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A standardized nomenclature for the rods and cones of the vertebrate retina

PLoS Biology, Journal Year: 2025, Volume and Issue: 23(5), P. e3003157 - e3003157

Published: May 7, 2025

Vertebrate photoreceptors have been studied for well over a century, but fixed nomenclature referring to orthologous cell types across diverse species has lacking. Instead, variably—and often confusingly—named according morphology, presence/absence of ‘rhodopsin’, spectral sensitivity, chromophore usage, and/or the gene family opsin(s) they express. Here, we propose unified vertebrate rods and cones that aligns with naming systems other retinal classes is based on photoreceptor type’s putative evolutionary history. This classification informed by functional, anatomical, developmental, molecular identities neuron as whole, including expression deeply conserved transcription factors required development. The proposed names will be applicable all vertebrates indicative widest possible range properties, their postsynaptic wiring, hence allude common species-specific roles in vision. Furthermore, system open-ended accommodate future discovery as-yet unknown types.

Language: Английский

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Birds multiplex spectral and temporal visual information via retinal On- and Off-channels

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Aug. 31, 2023

In vertebrate vision, early retinal circuits divide incoming visual information into functionally opposite elementary signals: On and Off, transient sustained, chromatic achromatic. Together these signals can yield an efficient representation of the scene for transmission to brain via optic nerve. However, this long-standing interpretation function is based on mammals, it unclear whether functional arrangement common all vertebrates. Here we show that male poultry chicks use a fundamentally different strategy communicate from eye brain. Rather than using pairs output channels, encode polarity, timing, spectral composition stimuli in highly correlated manner: fast achromatic encoded by Off-circuits, slow overwhelmingly On-circuits. Moreover, most channels combine On- Off-circuits simultaneously encode, or multiplex, both information. Our results birds conform evidence fish, amphibians, reptiles which retain full ancestral complement four types cone photoreceptors.

Language: Английский

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Comparative connectomics reveals noncanonical wiring for color vision in human foveal retina

Proceedings of the National Academy of Sciences, Journal Year: 2023, Volume and Issue: 120(18)

Published: April 25, 2023

The Old World macaque monkey and New common marmoset provide fundamental models for human visual processing, yet the ancestral lineage diverged from these lineages over 25 Mya. We therefore asked whether fine-scale synaptic wiring in nervous system is preserved across three primate families, despite long periods of independent evolution. applied connectomic electron microscopy to specialized foveal retina where circuits highest acuity color vision reside. Synaptic motifs arising cone photoreceptor type sensitive short (S) wavelengths associated with "blue-yellow" (S-ON S-OFF) color-coding circuitry were reconstructed. found that distinctive arises S cones each species. contacted neighboring L M (long- middle-wavelength sensitive) humans, but such contacts rare or absent macaques marmosets. discovered a major S-OFF pathway established its absence Further, S-ON chromatic pathways make excitatory-type types not Our results predict early-stage signals are distinct imply solving connectome at nanoscale level will be critical fully understanding neural basis vision.

Language: Английский

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