AHR and asthma: Using two well-characterized inbred mouse strains, AJ and B6, with contrasting susceptibility to develop AHR, a hallmark of asthma in humans, we demonstrate that inhibiting RA signaling during an early developmental window that encompasses initiation of the airway SM program results in transcriptional rewiring of a selected population of Tgfbi+ mesenchymal progenitors in AJ lungs.