| First Author | Nasr T | Year | 2020 |
| Journal | Dis Model Mech | PubMed ID | 33328171 |
| Mgi Jnum | J:302292 | Mgi Id | MGI:6506963 |
| Doi | 10.1242/dmm.046573 | Citation | Nasr T, et al. (2020) Disruption of a hedgehog-foxf1-rspo2 signaling axis leads to tracheomalacia and a loss of sox9+ tracheal chondrocytes. Dis Model Mech :dmm.046573 |
| abstractText | Congenital tracheomalacia, resulting from incomplete tracheal cartilage development, is a relatively common birth defect that severely impairs breathing in neonates. Mutations in the Hedgehog (HH) pathway and downstream Gli transcription factors are associated with tracheomalacia in patients and mouse models; however, the underlying molecular mechanisms are unclear. Using multiple HH/Gli mouse mutants including one that mimics Pallister-Hall Syndrome, we show that excessive Gli repressor activity prevents specification of tracheal chondrocytes. Lineage tracing experiments show that Sox9+ chondrocytes arise from HH-responsive splanchnic mesoderm in the fetal foregut that expresses the transcription factor Foxf1. Disrupted HH/Gli signaling results in 1) loss of Foxf1 which in turn is required to support Sox9+ chondrocyte progenitors and 2) a dramatic reduction in Rspo2, a secreted ligand that potentiates Wnt signaling known to be required for chondrogenesis. These results reveal a HH-Foxf1-Rspo2 signaling axis that governs tracheal cartilage development and informs the etiology of tracheomalacia. |
