Data Sheet 2_SST interneuron maturation extends beyond the second postnatal week and is driven by coordinated transcriptional and functional remodeling.pdf

Previous studies have suggested that key aspects of SST+ cIN maturation are largely established by the end of the second postnatal week. Here, we combined transcriptomic profiling and electrophysiological recordings to characterize the developmental trajectory of SST+ interneurons in the mouse neocortex from the second postnatal week through the end of the first postnatal month.

Bulk RNA sequencing of fluorescence-activated cell sorted SST+ cINs at P10, P15, and P30 revealed extensive transcriptional remodeling, including continued upregulation of genes associated with ion channel activity, synaptic transmission, and neuronal excitability beyond the second postnatal week. Consistent with these molecular changes, electrophysiological recordings demonstrated ongoing maturation of intrinsic and synaptic properties between P15 and P30.