Neely Delgueil, AlanDe Giorgis Oliva, Daniela2024-05-062024-05-062023-04https://repositoriobibliotecas.uv.cl/handle/uvscl/13765Voltage-gated Calcium Channels (CaV) are the main entryway for calcium influx into excitable cells. High Voltage-gated Calcium Channels (HVA) have four homologous but nonidentical repeats encompassing a voltage-sensing domain (VSD) and a quarter of the pore. In a physiological context, HVA can be modulated at least by two accessory subunits 2, and . In 1993, Neely et al. reported that CaV subunits could facilitate channel opening without altering gating currents' voltage dependence, suggesting that the energetic interaction between voltage sensors and the pore is modified. I tested this hypothesis using the Voltage Clamp Fluorometry technique to track the movement of human CaV1.2 individual VSDs in the presence or absence of CaV subunits. I expressed 1c pore-forming subunit with 2-1 in Xenopus oocytes and used the cut-open technique to implement voltage-clamp. I found that CaV modulates mostly VSD II with negligible impact on VSD III and VSD IV behavior and that this VSDII is moving in two steps.enCANALES DE CALCIOSENSORESFLUOROMETRIARegulation of voltage sensing structures of CaV1.2 calcium channel by the auxiliary β-subunitThesis