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Updated: Aug 7, 2026
08:33
Determination of Photoreceptor Cell Spectral Sensitivity in an Insect Model from In Vivo Intracellular Recordings
Published on: February 26, 2016
Evolving visual pigments: hints from the opsin-based proteins in a phylogenetically old "eyeless" invertebrate
Silvia Santillo1, Pierangelo Orlando, Luciano De Petrocellis
1Istituto di Cibernetica Eduardo Caianiello (ICIB), Consiglio Nazionale delle Ricerche (CNR), Via Campi Flegrei, 34 Comprensorio A Olivetti, Pozzuoli (Napoli), Italy.
Bio Systems
|July 18, 2006
Summary
Investigating Hydra
Area of Science:
- Vision research
- Molecular biology
- Evolutionary biology
Background:
- Opsin-based proteins are ubiquitous in metazoan visual systems.
- Metazoa possess non-visual photosensitive structures regulating physiology.
- Novel non-visual photopigments are a challenging research area.
Purpose of the Study:
- To investigate Hydra as a model for studying visual pigment differences.
- To explore molecular and functional aspects of extraretinal photoreception.
- To understand the evolution of visual pigments.
Main Methods:
- Overview of opsin-based protein subfamilies.
- Analysis of preliminary evidence for opsins in Hydra.
- Focus on molecular biology and evolutionary pathways.
Main Results:
- Hydra, an eyeless invertebrate, exhibits extraocular photoreception.
- Preliminary evidence for both image-forming and non-visual opsins in Hydra.
- Insights into Hydra's photoreception mechanisms.
Conclusions:
- Hydra serves as a valuable model for studying visual pigment evolution.
- The study provides new insights into the molecular biology of photoreception.
- Understanding opsin diversity is crucial for vision research.
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