University of Hawaii researcher Joanne Yew christened her newest gene discovery Spidey, after comic-book legend Spider-Man, for the way it can be manipulated to make vinegar flies stick to whatever they fly into.
The real superhero, however, could be Yew if the genetic find reaches its full potential in the realm of pest control.
Spidey the gene was described in a recently published study by an international team of researchers, led by Yew, who works for UH’s Pacific Biosciences Research Center.
Most insects have a wax coating that essentially makes them waterproof and protects them from microbes and environmental extremes.
Spidey, as it turns out, is an important gene in the waterproofing process of the vinegar fly, or Drosophila melanogaster, regulating the levels of a hormone that maintains those wax-producing cells.
The discovery occurred as Yew and her colleagues employed a genetic technique that allowed them to “knock out” individual genes in a specialized group of cells that line the abdomen and play a role in pheromone production.
“We were doing a genetic screen, a fishing expedition,” said Yew, a 1992 Maryknoll School graduate who initially launched the research three years ago at the National University of Singapore, where she was an assistant professor. Last year she returned home, accepting a position running a lab at UH-Manoa.
Over the course of three years the researchers tested 160 combinations of genes using the knockout technique.
One gene in particular stood out — the gene that would be named Spidey. When it was knocked out, according to the study, the flies exhibited several striking characteristics: Their lifespan was shortened by about 50 percent and they lost almost all of their waxy coating.
Without an adequate coat of waxy protection, many of the flies got stuck to the sides of the plastic vials and were unable to free themselves.
“This last feature was reminiscent of the comic book character Spider-Man, which is why we named the gene Spidey,” Yew said.
The steroid hormone that Spidey regulates is already well known for playing a key role in the development and metamorphosis of larvae in the vinegar fly. The scientists did not expect to learn that it also plays a central role in maintaining tissues in the adult fly, including the wax-producing cells.
Many other insects rely on a waterproof coating for their survival. Yew said exploiting and controlling the gene that regulates the coating could be useful for interfering with the mating behavior and lifespan of disease-bearing insects or agricultural pests.
Invasive pest species such as the oriental, Mediterranean and melon fruit flies are a major threat to agriculture across the globe, especially Hawaii. Many millions of dollars are spent annually trying to prevent fruit fly crop damage.
Adult female fruit flies lay eggs in the flesh of ripening and ripe fruits and vegetables. Once the eggs hatch, the maggots begin to feed within the fruit, causing it to ripen prematurely, rot and drop to the ground in a mushy inedible mess.
Yew said the researchers plan to investigate how the Spidey gene works in fruit flies and other insects.
Already, the Spidey gene has been identified in several other fly species with the help of Scott Geib,
a U.S. Department of Agriculture scientist in Hilo,
who is working on sequencing the genomes of pest
fruit fly species such as the Mediterranean, olive and melon fly.
“We plan to test whether Spidey plays the same role in other species as it does in Drosophila using genome editing methods,” Yew said.
In the meantime, Spidey takes its place among the many genes with evocative names identified in the Drosophila fly, which has been described as the poster child for genetics. Other vinegar fly genes include sonic hedgehog, which affects cell development; fruitless, which affects sexual orientation; and amnesiac, which affects memory.
With characteristics and behavior that make it easy to work with, the vinegar fly is a simple insect widely used in scientific research.
Yew’s latest work, published June 22 in the journal PLOS Genetics, was funded by the Singapore National Research Foundation, the UH-Manoa Office of the Vice Chancellor for Research and the Pacific Biosciences Research Center.