H. Ledford

“Whoosh!” bragged geneticist Michael Myre, spreading his fingers and pushing his hands away from his body. “That’s what they’ll do.”

‘Whoosh’ is not a word often applied to the slime mould Dictyostelium discoideum — affectionately called ‘Dicty’ by its devoted following of cell biologists and geneticists — but Myre, a researcher at Harvard Medical School in Boston, Massachusetts, was feeling confident. It was 16 May, the start of the great Dicty World Race, and Myre had faith that his entry would be the first to glide across the finish line of the 800-micrometre-long track.

The results, announced today, show that Myre was not far off in his prediction. His strains, which lack a Dicty gene that is similar to a human gene linked to a childhood neurological disorder called Batten disease, placed fourth in the race. The champion was a strain from the Netherlands, engineered to be more sensitive to a signaling molecule used in the race as a chemical attractant.

D. discoideum is called a ‘social amoeba’ because single cells swarm together to form multi-cellular structures. That behaviour also makes the cells ideal models of cell movement and migration. Biochemist Arjan Kortholt of the University of Groningen, a member of the team that submitted the fleet-pseudopodded winning strain, says that when Dicty hits its stride it moves like an ice skater, with a right-then-left gliding motion.

The Dicty World Race encouraged genetic and chemical doping — anything that would help researchers learn more about what makes the slime moulds swift and smart as they scurried through the maze-like race track and dashed towards high concentrations of a signaling molecule called cyclic-AMP.

The race also pitted Dicty against leukemia cells called HL60 cells. Those cells are typically faster than Dicty but have more difficulty negotiating complex mazes.

Bioengineer Daniel Irimia of the Massachusetts General Hospital in Boston hosted the race in his lab, and said he hoped the effort would call attention to the research while also introducing the community to tools they could use to standardize their cell migration assays. Kortholt says the race particularly captured the imagination of students, and he thinks may have attracted a few to his laboratory.

The winning team gets US$5000 and an opportunity to speak at the annual Dicty meeting in Germany this August. Kortholt says his team also plans to celebrate with drinks this week, and a barbeque, weather permitting.

Videos of all the contestants are available at the Dicty World Race site.