First discovery of animals making their own carotene

Washington, Apr 30 (ANI): In what could be called as the first among animals, insects, known as aphids, can make their own essential nutrients called carotenoids, say University of Arizona researchers.

To date, no other animals are known to make the potent antioxidants.

And scientists had been thinking that the only way animals could obtain the orangey-red compounds was from their diet.

"It is written everywhere that animals do not make carotenoids," said Nancy Moran, leader of the UA team that overturned the conventional wisdom.

Carotenoids are building blocks for molecules crucial for vision, healthy skin, bone growth and other key physiological functions. Beta-carotene, the pigment that makes carrots orange, is the building block for Vitamin A.

The researchers also figured out how the aphids they studied, known as pea aphids, acquired the ability to make carotenoids.

"What happened is a fungal gene got into an aphid and was copied," said Moran.

She added that, although gene transfers between microorganisms are common, finding a functional fungus gene as part of an animal's DNA is a first.

"Animals have a lot of requirements that reflect ancestral gene loss. This is why we require so many amino acids and vitamins in the diet. Until now it has been thought that there is simply no way to regain these lost capabilities. But this case in aphids shows that it is indeed possible to acquire the capacity to make needed compounds," she said.

"Possibly this will be an extraordinarily rare case. But so far in genomic studies, a single initial case usually turns out to be only an example of something more widespread."

A lucky accident in the lab plus the recent sequencing of the pea aphid genome made the discovery possible, said Moran.

The researchers have published their discovery in the latest issue of the journal Science. (ANI)