Ion channel regulation by G protein signaling pathways

Our research is focused on elucidating the molecular mechanisms that regulate ion channel activity by G protein signaling pathways in the brain and heart. In the brain, these cell signaling events modulate neuronal excitability and may cause or contribute to a number of neurologic and psychiatric disorders when pathologically altered (i.e. epilepsy, Parkinson's, schizophrenia, depression, drug abuse).

Current studies in my lab are investigating the role of "Regulators of G-protein Signaling" (RGS proteins) in modulating G protein-gated potassium (GIRK) channels that inhibit neuronal firing when activated by specific G protein-coupled receptors (GPCR's). RGS proteins represent a large family of recently discovered genes that accelerate the termination of G protein signaling. The specificity and molecular mechanisms involved in the assembly and regulation of GPCR-RGS-ion channel signaling complexes are currently not known. Our long-term goal is that these studies will lead to a better molecular understanding of the specific RGS proteins that modulate GIRK channel activity in the brain and heart, and thereby facilitate the rational design of therapeutic interventions in the treatment of brain and heart disorders.

Dr. Craig Doupnik is also investigating novel proteins and cell signaling pathways involved in neural control of heart rate.