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Vibratome Sectioning Mouse Retina to Prepare Photoreceptor Cultures

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Published on: December 22, 2014

Evolution of vertebrate retinal photoreception.

Trevor D Lamb¹

¹ARC Centre of Excellence in Vision Science, The Australian National University, Canberra ACT 0200, Australia. trevor.lamb@anu.edu.au

Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences

|September 2, 2009

Summary

The evolution of vertebrate photoreceptors and retina involved a closer relationship between ciliary and rhabdomeric photoreceptors than previously thought. This study proposes a scenario for their evolutionary steps, including cell class origins.

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A Bioinformatics Pipeline for Investigating Molecular Evolution and Gene Expression using RNA-seq

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Published on: May 28, 2021

Area of Science:

Evolutionary biology
Retinal cell biology
Photoreceptor evolution

Background:

Vertebrate ciliary photoreceptors and invertebrate rhabdomeric photoreceptors share more similarities than previously assumed.
Understanding photoreceptor evolution requires examining opsin phylogenies and retinal cell origins.

Purpose of the Study:

To elucidate the evolutionary steps leading to vertebrate photoreceptors and retina.
To propose a plausible evolutionary scenario based on recent findings.

Main Methods:

Phylogenetic analysis of ciliary and rhabdomeric opsins.
Integration of knowledge on retinoid pathways and photoreversal limitations.
Comparative analysis of vertebrate and invertebrate photoreceptor systems.

Main Results:

Ciliary and rhabdomeric photoreceptors are not entirely distinct.
Cones, rods, and bipolar cells likely evolved from a primordial ciliary photoreceptor.
Ganglion, amacrine, and horizontal cells likely evolved from rhabdomeric photoreceptors.

Conclusions:

A unified evolutionary pathway for vertebrate photoreceptors and retina is proposed.
Environmental factors like deep-ocean light levels may have influenced retinal evolution.
Molecular and circuitry differences between rods and cones provide insights into their evolution.