Itprid2-flox Mouse

Itprid2, also known as KRAS-induced actin-interacting protein (KRAP), is a cytoplasmic protein associated with filamentous-actin (F-actin). It plays a crucial role in regulating inositol 1,4,5-trisphosphate (IP3) receptor (IP3R) activity. IP3Rs are channels that regulate the redistribution of Ca2+ from the endoplasmic reticulum (ER) to the cytosol and other organelles. Itprid2 is involved in the Ca2+ signaling pathway, which is essential for various biological processes such as cell survival, adaptation, and death [2,3].

Studies in Itprid2-deficient mice have shown that loss of Itprid2 abolishes cytosolic and mitochondrial Ca2+ signals evoked by stimulation of IP3Rs via endogenous receptors. It is located at ER-mitochondrial membrane contact sites (ERMCSs) populated by IP3R clusters, and its loss reduces the number of ERMCSs. This indicates that Itprid2 regulates Ca2+ transfer from IP3Rs to mitochondria by licensing IP3R activity and stabilizing ERMCSs [1]. Additionally, knockdown of Itprid2 in cultured HEK293 or MCF7 cells diminishes ATP-induced Ca2+ release, suggesting its role in the proper regulation of IP3R-mediated Ca2+ release [4].

In conclusion, Itprid2 is essential for regulating IP3R-mediated Ca2+ release and Ca2+ transfer between the ER and mitochondria. Research using Itprid2-deficient mouse models has provided valuable insights into its role in the Ca2+ signaling pathway, which may have implications for understanding diseases related to abnormal Ca2+ signaling, such as certain types of cancer [1,4].