PIK3C2B, encoding for the class II phosphatidylinositol 3-kinase PI3K-C2β, is involved in lipid signalling and phosphorylates intracellular inositol lipids to regulate signalling and intracellular vesicular trafficking [2,4]. It is associated with pathways like AKT/mTOR, which play crucial roles in cell growth, metabolism, and autophagy [1].

In animal models, muscle-specific ablation of Pik3c2b in an Mtm1-deficient mouse model completely prevented the myotubular myopathy (MTM) phenotype, and postsymptomatic targeting promoted a striking rescue of the disease [3]. In zebrafish, certain PI3K inhibitors, which likely target PIK3C2B, prevented the development of the mtm phenotype [3]. Mutant Pik3c2b alleles in mice caused dose-dependent neuronal hyperexcitability and increased seizure susceptibility, indicating haploinsufficiency as a key driver of focal epilepsy [2]. Also, mice expressing a kinase-inactive form of PI3K-C2β displayed enlarged blood vessels due to mTORC1 activation in endothelial cells [4].

In conclusion, PIK3C2B is a critical regulator in multiple biological processes. Gene-knockout or conditional-knockout mouse models have revealed its significance in diseases such as focal epilepsy and MTM. Understanding PIK3C2B's function provides insights into disease mechanisms and potential therapeutic strategies for these conditions.