As aforementioned, in ADPKD, a decrease in ciliary Ca2+, due to loss of PC1 or PC2 function activates AC5/6, increasing intracellular cAMP and driving cystogenesis (Choi et al., 2011; Rees et al., 2014; Spirli et al., 2017; Wang et al., 2018). Here, PKD2 is linked to autosomal dominant polycystic kidney disease.