| First Author | Noch EK | Year | 2021 |
| Journal | J Comp Neurol | Volume | 529 |
| Issue | 2 | Pages | 434-449 |
| PubMed ID | 32449185 | Mgi Jnum | J:304474 |
| Mgi Id | MGI:6508660 | Doi | 10.1002/cne.24956 |
| Citation | Noch EK, et al. (2021) Distribution and localization of phosphatidylinositol 5-phosphate, 4-kinase alpha and beta in the brain. J Comp Neurol 529(2):434-449 |
| abstractText | Phosphatidylinositol-4,5-bisphosphate (PI-4,5-P2 ) is critical for synaptic vesicle docking and fusion and generation of the second messengers, diacylglycerol and inositol-1,4,5-trisphosphate. PI-4,5-P2 can be generated by two families of kinases: type 1 phosphatidylinositol-4-phosphate 5-kinases, encoded by PIP5K1A, PIP5K1B and PIP5K1C, and type 2 phosphatidylinositol-5-phosphate 4-kinases, encoded by PIP4K2A, PIP4K2B, and PIP4K2C. While the roles of the type 1 enzymes in brain function have been extensively studied, the roles of the type 2 enzymes are poorly understood. Using selective antibodies validated by genetic deletion of pip4k2a or pip4k2b in mouse brain, we characterized the location of the enzymes, PI5P4Kalpha and PI5P4Kbeta, encoded by these genes. In mice, we demonstrate that PI5P4Kalpha is expressed in adulthood, whereas PI5P4Kbeta is expressed early in development. PI5P4Kalpha localizes to white matter tracts, especially the corpus callosum, and at a low level in neurons, while PI5P4Kbeta is expressed in neuronal populations, especially hippocampus and cortex. Dual labeling studies demonstrate that PI5P4Kalpha co-localizes with the oligodendrocyte marker, Olig2, whereas PI5P4Kbeta co-localizes with the neuronal marker, NeuN. Ultrastructural analysis demonstrates that both kinases are contained in axon terminals and dendritic spines adjacent to the synaptic membrane, which support a potential role in synaptic transmission. Immunoperoxidase analysis of macaque and human brain tissue demonstrate a conserved pattern for PI5P4Kalpha and PI5P4Kbeta. These results highlight the diverse cell-autonomous expression of PI5P4Kalpha and PI5P4Kbeta and support further exploration into their role in synaptic function in the brain. |
