Newly deciphered ant genomes offer clues on ant social life, pest control

Washington, Feb 1 (ANI): An international team of scientists has decoded the genome of a persistent household pest -- the Argentine ant, an invasive species that is threatening native insects across the world.

The newly sequenced genomes of the Argentine ant (Linepithema humile) and the red harvester ant (Pogonomyrmex barbatus) could provide new insights on how embryos with the same genetic code develop into either queens or worker ants and may advance our understanding of invasion biology and pest control.

The scientists reported the results as part of a series of three decoded ant genomes, including the Argentine ant, the red harvester ant and the fire ant published in the Proceedings of the National Academy of Sciences.

In addition, the genome of the leaf cutter ant is scheduled for publication in the Feb. 24 issue of the Public Library of Science Genetics.

"We now know that ants have the genes and genome signature of DNA methylation -- the same molecular mechanism that published honeybee studies have shown is responsible for switching whether the genome is read to be a worker or queen," said Christopher D. Smith, assistant professor of biology at San Francisco State University, an author on three of the four genome studies.

Similar to bees, ants have sophisticated social structures. Queen ants typically have larger bodies, wings and fertile ovaries, and are responsible for reproduction in the colony. Worker ants are smaller, wingless and infertile, and are tasked with foraging for food and caring for the queen's offspring.

Analysis of these new ant genomes suggests that chemical modification of certain sections of DNA could be responsible for the differential development of queens and workers.

As an ant larva develops, DNA methylation, which involves methyl chemical groups attaching onto the DNA, may switch off the genes that control reproductive capacity and wing growth.

"Our analysis suggests that ants may utilize the same genetic system as honeybees to create their social structures, although we have yet to understand whether the process works in exactly the same way across species," Smith said.

Smith co-led the Argentine ant research with Neil Tsutsui of University of California, Berkeley; was a lead author on the red harvester ant genome along with Chris R. Smith of Earlham College and J|rgen Gadau of Arizona State University; and was a co-author on the leaf-cutter ant genome.

The mapping of the Argentine ant genome may enable the development of novel pest control solutions.

A better understanding of how larvae develop into queens or workers could support the development of new control methods that use more benign chemicals to limit the number of queens born in a colony, effectively sterilizing the population. (ANI)