Polycystic Kidney And Hepatic Disease 1 Protein (PKHD1)

PKHD1 is predicted to have a single transmembrane (TM)-spanning domain and multiple copies of an immunoglobulin-like plexin-transcription-factor domain. Alternative splicing results in two transcript variants encoding different isoforms. Other alternatively spliced transcripts have been described, but the full length sequences have not been determined. Several of these transcripts are predicted to encode truncated products which lack the TM and may be secreted. Mutations in this gene cause autosomal recessive polycystic kidney disease, also known as polycystic kidney and hepatic disease-1. The large protein encoded by PKHD1 contains multiple copies of a domain, TIG, shared with plexins and transcription factors. It was thought that fibrocystin may be a receptor protein that acts in collecting duct and biliary differentiation.