Cla4, or Inositol 1,4,5-trisphosphate receptor, type 1, is a human gene encoded by ITPR1. It may also be known as: Inositol 1,4,5-trisphosphate receptor type 1; IP3 receptor isoform 1; IP3R 1; InsP3R1; Type 1 inositol 1,4,5-trisphosphate receptor; Type 1 InsP3 receptor; protein phosphatase 1, regulatory subunit 94; ACV; CLA4; IP3R1; PPP1R94; SCA15; SCA16; SCA29. The encoded protein has an amino acid length of 2758 and a mass of 313.9 kDa. Other isoforms may exist. Cla4 is a member of the InsP3 receptor family. Homologs of this gene exist in other organisms, including: Mouse, Fly, Rat, Zebrafish, Frog, Chicken.