Protocol to dissect and dissociate the mouse brainstem for single-cell RNA-seq applications

Processing dissociated cells for transcriptomics is challenging when targeting small brain structures, like brainstem nuclei, where cell yield may be low. Here, we present a protocol for dissecting, dissociating, and cryopreserving mouse brainstem that allows asynchronous sample collection and downstream processing of cells obtained from brainstem tissue in neonatal mice. Although we demonstrate this protocol with the isolated preBötzinger complex and downstream SmartSeq3 cDNA library preparation, it could be readily adapted for other brainstem areas and library preparation approaches.