Acts as a positive regulator of hedgehog signaling and regulates ciliary function. Functions as a co-chaperone for CCT in the assembly of heterotrimeric G protein complexes, facilitates the assembly of both Gbeta-Ggamma and RGS-Gbeta5 heterodimers. Acts as a negative regulator of heterotrimeric G proteins assembly by trapping the preloaded G beta subunits inside the CCT chaperonin. Forms a complex with the beta and gamma subunits of the GTP-binding protein, transducin. Interacts with the CCT chaperonin complex. Expressed ubiquitously, highest levels are found in neural tissues amounting to 10% of total PDCL mRNA. Belongs to the phosducin family.