Assistant Professor, University of Texas Health Sciences Center-Houston
B.S., University of Delhi, India, 1997
Ph.D., University of Maryland School of Medicine, 2002
Postdoc, Johns Hopkins School of Medicine, MD, 2003-08
Signal transduction in the Drosophila nervous system
Every organism needs to adapt to changes in its environment to ensure optimal growth and survival. In eukaryotes, the nervous system is responsible for gathering and processing information concerning changes in both the internal and external environments. To achieve this vital task, all organisms employ a variety of sensory modalities. The gathered information is deciphered and processed via complex circuits; ultimately allowing the organism to respond in a manner which is best suited for its survival and growth under the changing conditions. Elucidation of the molecular pathways, signaling networks and neuronal circuits involved in this pas de deux between an organism’s environment and its survival is the long-term interest of our laboratory.
TRP channels constitute a super-family of cation channels conserved from yeast to humans. A unifying theme in the physiology of this remarkable family of proteins is that they play fundamental roles in sensory transduction. Not only do they allow organisms to detect changes in the external environment by mediating the classical Aristotelian senses of taste, touch, smell, sight and hearing, but they also allow individual cells and even intracellular organelles to respond to changes in their local environment! Therefore, it is not surprising that many human diseases arise due to mutations affecting TRP channel function.
In our laboratory, we study the physiological functions of TRP channels using Drosophila melanogaster as a model organism. Using a plethora of genetic and cell biological tools available for studying the neurobiology of Drosophila, we are engaged in understanding how these channels sense and transmit information to the nervous system. In addition to identifying the mechanisms involved in channel activation and regulation, we hope to map the neuronal circuits that utilize these channels. Keeping these goals in mind, the active areas of research in the lab at the moment are:
- Role of TRP channels in the maintenance of neuronal viability and prevention of neurodegeneration.
- Role of TRP channels in the regulation of developmental timing.
- Function of TRP channels in innate immunity, with particular emphasis on the bidirectional cross-talk between the nervous and immune systems.
Due to the broad areas of interest, we utilize a variety of eclectic tools to address these fundamental questions in neurobiology. These include classic cell biological, molecular and biochemical strategies, as well as state of the art optical imaging and electrophysiological approaches.
Ma HT, Venkatachalam K, Li HS, Montell C, Kurosaki T, Patterson RL, Gill DL (2001) Assessment of the role of the inositol 1,4,5-trisphosphate receptor in the activation of transient receptor potential channels and store-operated Ca2+ entry channels. Journal of Biological Chemistry 276:18888-18896.
Venkatachalam K, Ma HT, Ford DL, Gill DL (2001) Expression of functional receptor-coupled TRPC3 channels in DT40 triple receptor InsP3 knockout cells. Journal of Biological Chemistry 276:33980-33985.
Ma HT, Venkatachalam K, Rys-Sikora KE, He LP, Zheng F, Gill DL (2003) Modification of phospholipase C-gamma-induced Ca2+ signal generation by 2-aminoethoxydiphenyl borate. Biochemical Journal 376:667-676.
Venkatachalam K, Zheng F, Gill DL (2003) Regulation of canonical transient receptor potential (TRPC) channel function by diacylglycerol and protein kinase C. Journal of Biological Chemistry 278:29031-29040.
Venkatachalam K, Hofmann T, Montell C (2006) Lysosomal localization of TRPML3 depends on TRPML2 and the mucolipidosis-associated protein TRPML1. Journal of Biological Chemistry 281:17517-17527.
Venkatachalam K, Long AA, Elsaesser R, Nikolaeva D, Broadie K, Montell C (2008) Motor deficit in a Drosophila model of mucolipidosis type IV due to defective clearance of apoptotic cells. Cell 135:838-851.
Venkatachalam K, Wasserman D, Wang X, Li R, Mills E, Elsaesser R, Li HS, Montell C (2010) Dependence on a retinophilin/myosin complex for stability of PKC and INAD and termination of phototransduction. Journal of Neuroscience 30:11337-11345.
Wong CO, Li R, Montell C, Venkatachalam K (2012) Drosophila TRPML Is Required for TORC1 Activation. Current Biology 22:1616-1621.
Kartik Venkatachalam, Ph.D.
Department of Integrative Biology and Pharmacology
University of Texas Health Sciences Center-Houston
MSB 4.214, 6431 Fannin Street
Houston, Texas 77030, U.S.A.
Tel: (713) 500-7504