At the Daphnia Genomics Consortium's annual meeting in Bloomington this week, Indiana University and Joint Genome Institute scientists announced they've completed a "shotgun" sequence for Daphnia pulex, or the water flea, as it's better known to high school biology students.
"Daphnia is important to the environmental sciences, where the goal is to understand the complexities of ecosystems by getting a handle on how species in natural settings respond genetically to their environments," said Daphnia Genomics Project leader John Colbourne. "Ecologists and evolutionary biologists would also want to learn more about how genetic variation is important for adaptation and how populations survive in a changing world."
Colbourne is a founding member of the Daphnia Genomics Consortium and the genomics director of the Center for Genomics and Bioinformatics at IU Bloomington.
The U.S. Department of Energy and the National Science Foundation funded the Daphnia project. Most of the sequencing work was done at DOE's Joint Genome Institute Production Genomics Facility in Walnut Creek, Calif.
Shotgun sequencing involves breaking a whole genome into smaller, more digestible DNA segments, then sequencing each one. The Daphnia genome was sequenced over eight times to ensure better coverage of all 12 pairs of chromosomes.
Daphnia's short generation time and small genome (a mere 200 million base pairs) makes it an ideal organism for laboratory and field studies of how environments influence -- and how they're influenced by -- an organism's genetics. The animals are common in lakes and ponds and have been used to monitor the health of aquatic environments. Members of the species can reproduce both with and without sex, which has important implications in evolutionary b