Promotes ciliogenesis in renal epithelial cells and therefore participates in the tubules formation and/ or ensures the maintenance of the architecture of the lumen of the kidney (By similarity). Has an impact on cellular symmetry by ensuring correct bipolar cell division through the regulation of centrosome duplication and mitotic spindle assembly and by maintaining oriented cell division (OCD) during tubular elongation through planar cell polarity (PCP) pathway . During epithelial cell morphogenesis regulates also cell-cell and cell-matrix adhesion and participates in cell motility (By similarity). Promotes cell-cell contact through the positive regulation of PTK2 kinase activity leading to either positive regulation of epithelial cell proliferation through the HRAS/RAF1 pathways, or negative regulation of apoptosis through the PDK1/AKT1 pathway (By similarity). May act in collecting-duct and biliary differentiation . May participate in the regulation of the cholangiocytes proliferation and the CCN2 production in an CXCL8-dependent manner .
Subcellular locations: Cell membrane, Cytoplasm, Cell projection, Cilium, Cytoplasm, Cytoskeleton, Cilium basal body, Cytoplasm, Cytoskeleton, Spindle, Chromosome, Centromere, Apical cell membrane, Nucleus, Secreted, Extracellular exosome, Secreted, Endoplasmic reticulum, Golgi apparatus
The intracellular C-terminal fragment (ICD) translocates to the nucleus and is not detected in primary cilia (, ). The extracellular domain (PECD) traffics beyond the mid-Golgi and localizes on exosome like vesicles (ELVs) attached to the primary cilium (By similarity). In the urine, the extracellular domain (PECD) exists as an highly abundant secreted form and a less abundant PECD form that is either tethered to or shed with the C-terminal fragment (PTM) in ELVs (By similarity). The majority of full length PKHD1 protein resides at the endoplasmic reticulum and cannot pass beyond the mid-Golgi apparatus and is not detected in primary cilia (By similarity). The intra-cellular C-terminal fragment of 21-kDa translocates to the nucleus. The extracellular domain traffics beyond the mid-Golgi and localizes on exosome like vesicles (ELVs) attached to the primary cilium (By similarity).
Predominantly expressed in fetal and adult kidney. In the kidney, it is found in the cortical and medullary collecting ducts. Also present in the adult pancreas, but at much lower levels. Detectable in fetal and adult liver. Rather indistinct signal in fetal brain.