UNLV Assistant Professor of Life Sciences Allen Gibbs is the co-recipient of a three-year, $950,000 grant from the National Science Foundation to study how organisms adapt and survive in extremely arid environments, such as the Mojave and Sonoran deserts of the Southwestern United States.
Gibbs is collaborating with William Etges, professor of biological sciences at the University of Arkansas, to study how certain environmental stresses - such as extreme temperatures, lack of water and noxious chemicals produced by cacti - affect the genetic responses of desert fruit flies in the laboratory and in the wild. The results will be integrated with physiological and biochemical studies to identify which genes interact and allow the insect to survive in such harsh environmental conditions.
"Understanding how current biological communities function in arid environments may help us predict how other species will respond to the conditions predicted by global climate change models," said Gibbs. "The implications of understanding these genetic adaptions are significant, particularly when you consider the potential consequences of losing beneficial insect species, such as crop pollinators."
Approximately 40 percent of the earth's landmass is classified as arid or semi-arid, with that number expected to increase as a result of global climate change and human activity. Gibbs says the research will enhance understanding of how an animal's entire genome responds to environmental variability and stress by integrating available ecological, behavioral, genetic, and historical information about the desert fruit fly into their study.
Gibbs and Etges will study Drosophila mojavensis, a relative of the common laboratory fly, Drosophila melanogaster. Fruit flies are excellent genetic model systems for researchers to study because they reproduce quickly and can create many generations in a short time span. Gibbs calls this species the "bionic" fly, because it has to survive temperatures from over 100 degrees Fahrenheit to below freezing and sustain long periods without water, all while living and growing in cacti containing dozens of toxic chemicals. The desert fruit fly is the only desert plant or animal whose genome has been fully sequenced, allowing scientists to more easily analyze and manipulate relationships between various genes and environmental conditions.
Gibbs and Etges will use DNA microarrays - slides containing microscopic DNA spots, each representing a different gene in the fruit fly genome - to determine what genes are being used to help the fruit fly survive under various environmental conditions. To do so, they will collect fruit flies from different locations under varying degrees of temperature and water stress and extract their RNA - the chemical that contains the information about what genes are being expressed during those conditions. They will then copy that RNA into fluorescent DNA. Copies of expressed genes will then stick to specific spots on the microarray, providing a "map"of the genes that are being expressed and those that are not.
During the course of the study, several undergraduate and graduate students, as well as post-doctoral researchers, will receive training and become an integral part of the research. The grant is one of three NSF awards received in the past month by the UNLV School of Life Sciences, totaling more than $2.1 million.
