inositol 1,3,4,5-tetrakisphosphate

Inositol 1,3,4,5-tetrakisphosphate (IP₄) is a naturally occurring small molecule and a member of the inositol polyphosphates family. It is produced by phosphorylation of inositol trisphosphates and acts as a second messenger involved primarily in cellular calcium signaling. IP₄ increases intracellular calcium levels by two distinct mechanisms: it can open calcium channels on the endoplasmic reticulum to release stored Ca²⁺ and also increase entry of Ca²⁺ across the plasma membrane[2][9][10]. It is functionally related to myo-inositol and plays roles as a metabolite and signaling molecule within cells[1][3]. In addition to its role as a second messenger for Ca²⁺ mobilization[8], it has been reported to act as an inhibitor or regulator of certain phosphatases involved in phosphoinositide metabolism[6]. Experimental evidence suggests that IP₄ may also interact with tyrosine-protein kinase BTK (Bruton's tyrosine kinase), although this mechanism remains less well characterized[4].

Other names

inositol 1,3,4,5-tetrakisphosphatemyo-inositol 1,3,4,5-tetrakisphosphateinositol 1,3,4,5-tetraphosphateD-myo-inositol 1,3,4,5-tetrakis(phosphate)102850-29-3