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bioRxiv · 10.1101/2021.08.01.454659

Transcriptomes of Electrophysiologically Recorded Dbx1-derived Inspiratory Neurons of the preBötzinger Complex in Neonatal Mice

Kallurkar, P. S.·Picardo, M. C.·Sugimura, Y.·Saha, M. A.·Conradi Smith, G. D.·Del Negro, C. A.
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Abstract

Breathing depends on interneurons in the preBotzinger complex (preBotC) derived from Dbx1-expressing precursors. Here we investigate whether rhythm- and pattern-generating functions reside in discrete classes of Dbx1 preBotC neurons. In a slice model of breathing with [~]5 s cycle period, putatively rhythmogenic Type-1 Dbx1 preBotC neurons activate 100-300 ms prior to Type-2 neurons, putatively specialized for output pattern, and 300-500 ms prior to the inspiratory motor output. We sequenced Type-1 and Type-2 transcriptomes and identified differential expression of 123 genes including ionotropic receptors (Gria3 and Gabra1) that may explain their preinspiratory activation profiles and Ca2+ signaling (Cracr2a, Sgk1) involved in inspiratory and sigh bursts. Surprisingly, neuropeptide receptors that influence breathing (e.g., {micro}-opioid and bombesin-like peptide receptors) were only sparsely expressed, which suggests that cognate peptides and opioid drugs exert their profound effects on a small fraction of the preBotC core. These data in the public domain help explain breathings neural origins.

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Kallurkar, P. S., Picardo, M. C., Sugimura, Y., Saha, M. A., Conradi Smith, G. D., Del Negro, C. A.. 2021-08-02. Transcriptomes of Electrophysiologically Recorded Dbx1-derived Inspiratory Neurons of the preBötzinger Complex in Neonatal Mice. https://doi.org/10.1101/2021.08.01.454659

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