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Updated: Aug 14, 2026
12:50
Using Whole Mount in situ Hybridization to Link Molecular and Organismal Biology
Published on: March 31, 2011
Visual pigment homologies revealed by DNA hybridization
Science (New York, N.Y.)
|June 6, 1986
Summary
Photosensory pigments, like rhodopsin, share a common evolutionary origin across diverse species. This study found homologous visual pigment genes in vertebrates, invertebrates, and even single-celled organisms, suggesting ancient ancestry.
Area of Science:
- Molecular Biology
- Evolutionary Biology
- Genetics
Background:
- Visual pigments are crucial for light detection in many organisms.
- Rhodopsin, a key visual pigment, has been extensively studied in vertebrates.
Purpose of the Study:
- To investigate the evolutionary origins of visual pigment genes.
- To identify homologous genes across a wide range of species using a bovine rhodopsin probe.
Main Methods:
- DNA hybridization techniques were employed to detect gene homology.
- Stringent and reduced stringency conditions were used to identify homologous fragments.
- A bovine rhodopsin complementary DNA probe was utilized.
Main Results:
- A single homologous fragment was found in most vertebrate genomic DNA under stringent conditions.
- Reduced stringency revealed additional homologies in some vertebrates.
- Homologous fragments were also detected in invertebrates, a unicellular alga, and an archaebacterium.
- Many fragments showed homology to a Drosophila opsin probe.
Conclusions:
- Photosensory pigments likely evolved from a common ancestral precursor.
- Gene homology suggests a shared evolutionary history for visual pigments across diverse taxa.
- The findings support the deep evolutionary roots of light-sensing mechanisms.
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