Dorsal root ganglia (DRG) are diverse clusters of somatosensory neurons and glia involved in detecting sensory stimuli. A recent study in Cell from Lu, Wang and colleagues provides a single-nucleus RNA-sequencing atlas of human DRG development from gestational week (GW) 7 to GW21. The researchers identified two waves of neurogenesis, during which DRG neural crest cells differentiate into large sensory neurons including proprioceptors or mechanoreceptors (GW7–8) and small sensory neurons including nociceptors (GW7–12), respectively. After GW12, neural crest cells adopt more glial fates and differentiate into satellite glial cells (GW12–15) or Schwann cells (GW17–21). By comparing their data to previous single-cell studies in mice, the authors reported that human DRG development from GW7 to GW21 follows a similar trajectory to mouse DRG from embryonic day 12 to postnatal day 4. Additionally, human and mouse DRG differed in the extent and timing of nociceptor-related gene expression, which suggests that these species exhibit similar developmental profiles but on different time scales. Lastly, the authors developed a method for generating human DRG organoids from embryonic stem cells. After 60 days of differentiation, these organoids displayed cell-type composition and transcriptomic signatures similar to those of human DRG samples from GW7 to GW15. Altogether, this study provides a valuable transcriptomic resource and experimental model to explore the process of human DRG development.

Original reference: Cell 187, 7374–7393.e28 (2024)