ITPKC

The ITPKC gene provides instructions for making one version (isoform) of the inositol 1,4,5-trisphosphate 3-kinase (ITPK) enzyme. This enzyme helps add a cluster of oxygen and phosphorus atoms (a phosphate group) to a molecule called Ins(1,4,5)P3 to produce a molecule called Ins(1,3,4,5)P4. Both of these molecules are involved in regulating the amount of calcium in cells.

Several versions (isoforms) of the ITPK enzyme are produced from different genes. They play a variety of roles in processes throughout the body. The isoform produced from the ITPKC gene is called inositol 1,4,5-trisphosphate 3-kinase C (ITPKC). It is involved in a mechanism called the Ca(2+)/NFAT signaling pathway, which is affected by calcium levels. This pathway helps limit the activity of immune system cells called T cells. T cells identify foreign substances and defend the body against infection. Reducing the activity of T cells when appropriate prevents the overproduction of immune proteins called cytokines that lead to inflammation and which, in excess, cause tissue damage.

Kawasaki disease - increased risk from variations of the ITPKC gene

A variation in the ITPKC gene has been associated with an increased risk of Kawasaki disease, a sudden and time-limited (acute) illness affecting infants and children resulting in prolonged fever, inflammation, and other signs and symptoms. The variation changes a single DNA building block (nucleotide) in a region of the gene known as intron 1. It appears to reduce the efficiency of ITPKC gene transcription, which is the first step in producing the ITPKC enzyme. Researchers suggest that the variation may reduce the amount of ITPKC enzyme and interfere with the body's ability to limit T cell activity, leading to inflammation that damages blood vessels and results in the signs and symptoms of Kawasaki disease.