We are focusing on the fly visual system to dissect the mechanisms of activation and transport of the founding TRP channel, and the light receptor, rhodopsin. In addition, we are unraveling unconventional roles for rhodopsins.
We are defining the taste receptors and cells that explain how fruit flies discriminate different types of chemicals in foods, and how flies undergo plastic changes in their taste preferences in response to long-term exposure to different diets.
Our lab is dissecting the cellular and molecular mechanisms through Drosophila is able to discriminate very small differences in comfortable temperature range. We found that this behavior is mediated in part through a thermosensory signaling cascade that is initiated by rhodopsin and culminates with activation of the TRPA1 channel.
Rhodopsins are ancient and evolutionarily conserved light receptors. Based on >100 years of study, the dogma was that they function exclusively in light reception. Our recent and ongoing work challenges this tenet. We uncovered the first light-independent role for these evolutionarily conserved light sensors. Remarkably, opsins enable fruit flies to discriminate between tiny temperature differences within the comfortable range.
Courtship and mating in Drosophila depends on visual, auditory, olfactory and gustatory cues. Male-male aggression also depends on information obtained from these senses. We are decoding the cells, receptors and neurotransmitters employed for sensing and transmitting signals initiated by pheromones that promote male-female courtship, male-male aggression, and suppress male-male courtship.
Plants and insects have complex relationship. While some insects are pollination vectors, many insects feed on plants and are therefore detrimental. Therefore, plants produce both volatile and non-volatile chemicals to ward away insect pests. We are identifying the receptors and ion channels that sense naturally occurring repellents and insecticides produced by plants.
Circadian rhythms are one of the most fundamental processes in nature. Organisms ranging from cyanobacteria to plants and animals exhibit physiological or behavioral changes that are set by the circadian cycle. The fruit fly, Drosophila melanogaster, senses day/night cycles in part through rhodopsin-dependent light reception in their classoca. However, a more significant pathway for light entrainment is mediated in central pacemaker neurons. The Drosophila circadian clock is extremely light sensitive.
Among the most devastating infectious diseases worldwide are insect-borne diseases that are spread by mosquitoes. One such mosquito vector, Aedesaeypti, is of particular concern because it spreads the viruses that cause diseases such as Dengue and Zika, which are increasing in incidence. Using molecular genetic approaches, our laboratory is developing transgenic forms of Aedes aeypti that are intended to eliminate this insect vector.