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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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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The vertebrate retina: a window into the evolution of computation in the brain

Current Opinion in Behavioral Sciences, Journal Year: 2024, Volume and Issue: 57, P. 101391 - 101391

Published: April 17, 2024

Animal brains are probably the most complex computational machines on our planet, and like everything in biology, they product of evolution. Advances developmental palaeobiology have been expanding general understanding how nervous systems can change at a molecular structural level. However, these changes translate into altered function — that is, 'computation' remains comparatively sparsely explored. What, concretely, does it mean for neuronal computation when neurons their morphology connectivity, new appear or old ones disappear, transmitter slowly modified over many generations? And evolution use possible knobs dials to constantly tune give rise amazing diversity animal behaviours we see today? Addressing major gaps benefits from choosing suitable model system. Here, I present vertebrate retina as one perhaps unusually promising candidate. The is ancient displays highly conserved core organisational principles across entire lineage, alongside myriad adjustments extant species were shaped by history visual ecology. Moreover, logic readily interrogated experimentally, existing retinal circuits handful serve an anchor exploring circuit adaptations tree life, fish deep aphotic zone oceans eagles soaring high up sky.

Language: Английский

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Restoration of cone-circuit functionality in the regenerating adult zebrafish retina

Developmental Cell, Journal Year: 2024, Volume and Issue: 59(16), P. 2158 - 2170.e6

Published: Aug. 1, 2024

Unlike humans, teleosts like zebrafish exhibit robust retinal regeneration after injury from endogenous stem cells. However, it is unclear if regenerating cone photoreceptors regain physiological function and integrate correctly into post-synaptic circuits. We used two-photon calcium imaging of living adult retina to examine photoreceptor responses before light-induced lesions. To assess functional recovery cones downstream outer circuits, we exploited color opponency; UV intrinsic Off-response blue light, but On-response green which depends on feedback signals Accordingly, assessed the presence quality Off- vs. On-responses found that regenerated both Off-responses short-wavelength long-wavelength light within 3 months lesion. Therefore, circuit functionality restored in photoreceptors, suggesting inducing a promising strategy for human repair.

Language: Английский

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On analogies in vertebrate and insect visual systems

Nature reviews. Neuroscience, Journal Year: 2025, Volume and Issue: unknown

Published: May 23, 2025

Language: Английский

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Comparative transcriptomic insights into the evolutionary origin of the tetrapod double cone

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 6, 2024

The tetrapod double cone is a pair of tightly associated cones called the "principal" and "accessory" member. It found in amphibians, reptiles, birds, as well monotreme marsupial mammals but absent fish eutherian mammals. To explore potential evolutionary origins cone, we analyzed single-cell -nucleus transcriptomic atlases photoreceptors from six vertebrate species: zebrafish, chicken, lizard, opossum, ground squirrel, human. Computational analyses separated principal accessory members chicken identifying molecular signatures distinguishing either member single rods same species. Comparative suggest that both originated ancestral red cones. Furthermore, gene expression variation among subtypes mirrors their spectral order (red

Language: Английский

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Conservation of cis-regulatory codes over half a billion years of evolution

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 14, 2024

ABSTRACT The identification of homologous cell types across species represents a crucial step in understanding type evolution. retina is particularly amenable to comparative analysis because the basic morphology, connectivity, and function its six major classes have remained largely invariant since earliest stages vertebrate Here, we show that retina’s highly conserved cellular architecture mirrored by deep conservation underlying cis -regulatory codes control gene expression. We use single-cell chromatin accessibility lamprey, fish, bird, mammalian retinas— representing over half billion years evolutionary divergence—to demonstrate cross-species all retinal classes. This persists despite extensive turnover regions between distant species. Conservation manifests as clustering multiple distinct high-affinity transcription factor (TF) binding sites toward center cell-class-specific open with little preservation higher-order syntax. Hierarchical machine-learning models from diverse recovers clusters corresponding Thus, Bauplan controlled which predate divergence extant vertebrates persist nearly complete enhancer turnover.

Language: Английский

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A heterogeneous population code at the first synapse of vision

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: May 5, 2024

SUMMARY Vision begins when photoreceptors convert light fluctuations into temporal patterns of glutamate release that drive the retinal network. The input-output relation at this first stage has not been systematically measured in vivo so it is known how operates across a photoreceptor population. Using kHz-rate imaging zebrafish, we find individual red cones encode visual stimuli with high reliability and time-precision, but routinely vary sensitivity to luminance, contrast, frequency Variations relations are generated by feedback from horizontal cell network effectively decorrelate feature representation. A model capturing zebrafish sample their environment indicates heterogeneity expands dynamic range retina improve coding natural scenes. Moreover, different kinetic components used distinct stimulus features parallel: sustained linearly encodes low amplitude dark contrasts, transient large contrasts. Together, study reveals an unprecedented degree functional within same-type illustrates separation synapse vision.

Language: Английский

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