Preliminary functional characterization of a calcium-sensing receptor, polycystin-2 channel complex in the plasma membrane of LLC-PK1 cells

SCARINCI N; PEREZ PL; CANTERO MR; CANTIELLO HF

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2017

Polycystin-2 (PC2, TRPP2) is TRP-type, Ca2+-permeable nonselective cation channel. PC2 is encoded by the PKD2 gene, whose mutations are responsible for autosomal dominant polycystic kidney disease (ADPKD). PC2 has been detected in different cellular locations, including the plasma membrane, the endoplasmic reticulum, and the primary cilium. Recent studies from our laboratory (Dai et al 2017) determined that a plasma membrane PC2 is regulated by changes in external Ca2+ concentrations in wild type LLC-PK1 renal epithelial cells. The stimulatory effect of high external Ca2+ on the PC2-mediated whole-cell currents was mimicked by agonists of the Calcium-Sensing Receptor (CaSR), including spermine, gentamicin, and the calcimimetic R-568. CaSR was also identified, and observed to co-immuno-localize with the PC2 channel protein in a manner that depended on external Ca2+. The present study explored the effect of Ca2+ and CaSR agonists in the regulation of PC2 function in isolated plasma membranes from LLC-PK1 cells.