Education

PhD in Biochemistry, Montana State University, 2013

Lab information

Voltage sensing phosphatases (VSP) bridge two fundamental cell signals, voltage and phosphatidylinositol phosphate (PIPs) concentrations, through voltage regulated enzyme catalysis. The voltage sensing domain (VSD) from VSP senses membrane voltage changes triggering the cytosolic phosphatase domain (PD) to dephosphorylate PIPs. VSP activity directly links voltage to PIP concentrations, both of which are key components in cell excitability, migration and immune response. Although, we understand what reactions are catalyzed by VSP, the underlying biophysics and the physiological role are still unclear. Hence, understanding the biophysics of VSPs will play a critical role in identifying the biological context. My post-doctoral work in Dr. Kohout’s lab has shown that VSP from Ciona intestinalis (Ci-VSP) dimerizes predominantly through the VSD and that Ci-VSP dimers can act in a dominant-negative fashion. This is a paradigm shift in the VSP field. Ci-VSP was functionally considered a monomer although that work was done only at a single, low concentration of protein. My work in the paper explored a range of Ci-VSP concentrations and proved that the dimerization of Ci-VSP is a concentration dependent process. I utilized two-electrode voltage clamp fluorometry, co-immunoprecipitation and FRET based measurements to test Ci-VSP’s dimerization capability and its in vivo phosphatase activity. The functional impact of dimerization in VSPs across species could ultimately reveal how they may be involved in voltage dependent PIP signaling in cells.
http://www.montana.edu/cbn/faculty-staff/kohout.html

Publications