Emily Liman, Ph.D.

Laboratory of Sensory Neurobiology, USC

Work in the Liman laboratory is focused on understanding sensory information is detected and transduced, using a combination of electrophysiology, molecular biology, genetics and genomics. Professor Liman trained with Linda Buck, in whose lab she cloned and characterized sensory transduction components of the main olfactory and vomeronasal sysmtes (see Liman and Buck, 1992 for an example).  As a research assisitant professor at Harvard she identified an ion channel essential for pheromone detection in vertebrates (TRPC2; see Liman, Corey and Dulac, 1999 for an example).  Interestingly, this protein is not found in humans (it is encoded by a pseudogene), indicating that humans have lost much of their ability to respond to pheromones. Work in the Liman lab showed that the functional protein was lost in human evolution at the same time that humans developed trichromatic vision, suggesting that vision has replaced pheromone detection in human reproductive biology (Liman and Innan, 2003).

Ongoing work in the Liman lab is focused on mechanisms of taste signaling, mechanisms of pain signaling, and the identification of ion channels that contribute to these processes. In recent work, we showed that an ion channel responsible for the detection of spicy mustards, TRPA1, is also activated by carbon dioxide (Wang et al, 2010). This may explain some of the pungency we feel when we drink carbonated beverages. In a separate study, we examined the mechanism of taste transduction using genetically modified mice in which subsets of taste cells are fluorescently labeled. Using patch clamp electrophysiology and uv-uncaging of protons we showed that sour taste is mediated by an apically located proton channel (Chang et al, 2010). Future experiments in the lab are aimed at identifying the molecular nature of this proton channel. The lab uses methods of molecular biology, including generation of transgenic animals, combined with patch clamp electrophysiology and calcium imaging.

Emily Liman, Ph.D. is an assoicate professor of Biological Sciences, in the Section of Neurobiology at the University of Southern California.