2022 Volume 6 Issue 2 Pages 93-100
Phosphoinositides (PIPs), which are phosphorylated forms of phosphatidylinositol (PI), are minor but essential components of membrane phospholipids. There are seven PIP classes differing in phosphorylation at the 3, 4, and 5 positions of the inositol ring of PI. Each PIP class plays crucial roles in various cellular events, such as signal transduction and membrane trafficking, while dysregulation of PIP metabolism is associated with the development of diseases such as cancer. Recent studies suggest the importance of the composition of the two fatty acyl chains in PIPs as well as the phosphorylation status of the inositol ring of PIPs. Therefore, there is an increasing demand for analysis of PIPs by mass spectrometry which can provide information on the fatty acyl chains of PIPs. Recently, mass spectrometric methods that can comprehensively analyze molecular species of all PIP regioisomers have been developed. In this short review, we describe past and present mass spectrometric analyses of PIPs as well as potential future improvements in the method.
