Augmented BMP4 signal impairs tongue myogenesis

Tongue muscles are derived from mesodermal cells, while signals driven by cranial neural crest cells (CNCCs) regulate tongue myogenesis via tissue-tissue interaction. Based on such mechanisms of interaction, congenital tongue defects occur in CNC-related syndromes in humans. This study utilized a pathologic model for the syndrome of congenital bony syngnathia, Wnt1-Cre;pMes-Bmp4 mouse line, to explore impacts of enhanced CNCCs-originated BMP4 signal on tongue myogenesis via tissue-tissue interaction. Our results revealed that microglossia, a clinical phenotype of congenital bony syngnathia in humans exhibited in Wnt1-Cre;pMes-Bmp4 mice due to impaired myogenesis. The augmented BMP4 signal affected the distal distribution, proliferation, and differentiation of myogenic cells as well as tendon patterning, resulting in disarrangement and atrophy of tongue muscles and the loss of the anterior digastric muscle. This study demonstrated how a CNCCs-originated ligand impaired tongue myogenesis via a non-autonomous way, which provided potential formation mechanisms for understanding tongue abnormalities in CNC-related syndromes.

Automated summary

The study found that enhanced BMP4 signal originating from CNCCs led to impaired tongue myogenesis in the Wnt1-Cre;pMes-Bmp4 mouse model, resulting in microglossia similar to the clinical phenotype of congenital bony syngnathia in humans. The augmented BMP4 signal affected the distribution, proliferation, differentiation of myogenic cells, as well as tendon patterning, leading to disarrangement and atrophy of tongue muscles and the loss of the anterior digastric muscle. This study demonstrated how CNCCs-derived BMP4 signal can impair tongue myogenesis through tissue-tissue interaction, providing insights into the formation mechanisms of tongue abnormalities in CNC-related syndromes.