Exploring the Pannexin 1 interactome:In silicocross-analyses with postsynaptic proteins and neuropsychiatric disorder susceptibility genes

Abstract

The Pannexin 1 (Panx1) channel-forming protein is enriched in the central nervous system, and has been associated with several critical neurodevelopmental and plasticity functions; these include dendritic spine formation, neuronal network development, synaptic plasticity, and pathological brain states such as ischemia, epilepsy, and neurodegeneration. Despite major advances in understanding the properties and activation modes of Panx1, the Panx1 interactome remains largely uncharacterized. Considering that Panx1 has been implicated in critical neurodevelopmental and neurodegenerative processes and diseases, we investigated the Panx1 interactome (482 Panx1-interacting proteins) identified from mouse N2a cells. These proteins were cross-analyzed with the postsynaptic proteome of the adult mouse brain previously identified by mass spectrometry (LC-MS/MS), and neurodegenerative disease and neurodevelopmental disorder susceptibility genes previously identified by genome-wide association studies (GWAS); and then further investigated using various bioinformatics tools (PANTHER, GO, KEGG and STRING databases). A total of 104 of the Panx1-interacting proteins were located at the postsynapse, and 99 of these formed a 16-cluster protein-protein interaction (PPI) network (hub proteins: Eef2, Rab6A, Ddx39b, Mapk1, Fh1, Ndufv1 et cetera). The cross-analysis led to the discovery of proteins and candidate genes involved in synaptic function and homeostasis. Of particular note, our analyses also revealed that certain Panx1-interacting proteins are implicated in Parkinson disease, Alzheimer disease, Huntington disease, amyotrophic lateral sclerosis, schizophrenia, autism spectrum disorder and epilepsy. Altogether, our work revealed important clues to the role of Panx1 in neuronal function in health and disease by expanding our knowledge of the PPI network of Panx1, and unveiling previously unidentified Panx1-interacting proteins and networks involved in biological processes and disease.