Abstract
The pkd1 and pkd2 genes encode for the proteins polycystin-1 (PC1) and polycystin-2 (PC2). These genes are mutated in patients diagnosed with autosomal dominant polycystic kidney disease. PC1 and PC2 interact via their C-terminal, cytosolic regions, which is an essential step in the regulation of cell proliferation and differentiation. Here, we developed an assay that allowed us to quantitatively ...
Abstract
The pkd1 and pkd2 genes encode for the proteins polycystin-1 (PC1) and polycystin-2 (PC2). These genes are mutated in patients diagnosed with autosomal dominant polycystic kidney disease. PC1 and PC2 interact via their C-terminal, cytosolic regions, which is an essential step in the regulation of cell proliferation and differentiation. Here, we developed an assay that allowed us to quantitatively monitor the interaction of the C-terminal region of PC1 (cPC1) with that of PC2 (cPC2) to be able to answer the question of how Ca2+ influences the PC1/PC2 complex formation. By means of the quartz crystal microbalance (QCM) technique, we were able to determine binding affinities and kinetic constants of the cPC1/cPC2 interaction using a model based on the scaled particle theory. The results suggest that cPC2 forms trimers in solution in the absence of Ca2+, which bind in a one step process to cPC1. (C) 2010 Elsevier B.V. All rights reserved.