Differential Expression of GABRD Modulates GABA-Mediated Tonic Inhibition in Parvalbumin- and Somatostatin-Positive Interneurons in Mouse Hippocampus

Inhibitory interneurons are essential for the organization and regulation of neuronal circuity to attune brain functions. Dysfunction of inhibitory interneurons is associated with multiple neurological disorders. The two major types of inhibitory interneurons, parvalbumin-positive (PV+) and somatostatin-positive (SST+) interneurons, have distinct physiological function but both are critical for information processing and memory formation in the hippocampus. However, the molecular mechanisms regulating the specialized roles of PV+ and SST+ interneurons remains unclear. We utilized the ribosome tagging (RiboTag) approach to compare the transcriptome of PV+ and SST+ interneurons in the hippocampus. Our results indicated that the expression of voltage-gated ion channels and GABAA receptor-related genes are distinct between PV+ and SST+ interneurons. Part of differential expressed genes between these two interneurons are associated with schizophrenia and epilepsy. Our results provide insight into the molecular mechanism underlying the difference in tonic inhibition of PV+ and SST+ interneurons.