Lesson plan
Torulene
Torulene (3',4'-didehydro-β,γ-carotene) is a carotene (a hydrocarbon carotenoid) which is notable for being synthesized by red pea aphids (Acyrthosiphon pisum), imparting the natural red color to the aphids, which aids in their camouflage and escape from predation. The aphids have gained the ability to synthesize torulene by horizontal gene transfer of a number of genes for carotenoid synthesis, apparently from fungi. Plants, fungi, and microorganisms can synthesize carotenoids, but torulene made by pea aphids is the only carotenoid known to be synthesized by an organism in the animal kingdom at the time of its discovery (2010). In 2012, the spider mite Tetranychus urticae was found to produce its own caretinoids using homologous genes, likely derived from similar fungi. In 2013, the Acyrthosiphon caretinoid synthesis genes were found to be present in aphid relatives, adelgids and phylloxerids.
Article summary
Torulene (3',4'-didehydro-β,γ-carotene) is a carotene (a hydrocarbon carotenoid) which is notable for being synthesized by red pea aphids (Acyrthosiphon pisum), imparting the natural red color to the aphids, which aids in their camouflage and escape from predation. The aphids have gained the ability to synthesize torulene by horizontal gene transfer of a number of genes for carotenoid synthesis, apparently from fungi. Plants, fungi, and microorganisms can synthesize carotenoids, but torulene made by pea aphids is the only carotenoid known to be synthesized by an organism in the animal kingdom at the time of its discovery (2010). In 2012, the spider mite Tetranychus urticae was found to produce its own caretinoids using homologous genes, likely derived from similar fungi. In 2013, the Acyrthosiphon caretinoid synthesis genes were found to be present in aphid relatives, adelgids and phylloxerids.
Key claims
No claims recorded.
Discussion questions
- Summarise the article in your own words. Which single claim would you verify first, and why?
- Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
- If two sources disagreed about one of these facts, what would you need in order to trust one over the other?
Bibliography
No sources recorded.
Key claims and bibliography are generated from the same tracked claims and sources as the article page.