Figure 10From: Lung mesenchymal expression of Sox9plays a critical role in tracheal developmentConcept diagram of Sox9 function in lung development. Sox9 acts downstream of Tbx4/5[6]. Sox9 feeds back negatively on Tbx4 and Tbx5 in the tracheal mesenchyme. Cartilage ring formation requires functional Sox9 expression in the tracheal mesenchyme. Lack of cartilage rings induce altered tracheal epithelium differentiation (increased Clara cells, and decreased basal and goblet cells) and defective development of tracheal vasculature structurest.Back to article page