Mutations in IRF6 (interferon regulatory factor 6) cause isolated and syndromic forms of cleft lip and palate – birth defects affecting the upper lip and roof of the mouth. Recent reports suggest IRF6 may also be expressed in other developing tissues, including the tongue.
Steven Goudy, M.D., associate professor of Otolaryngology, and colleagues explored potential roles for IRF6 in tongue development. They report Feb. 22 in PLoS ONE that IRF6 is expressed in cells that give rise to the tongue musculature (Myf5+ cells). In the absence of IRF6, the number of Myf5+ cells is reduced, and the cells are poorly organized and have aberrant cytoskeletal structures. The researchers show that IRF6 also influences the proliferation of cranial neural crest cells that give rise to tongue connective tissue.
The findings demonstrate that IRF6 plays important roles in muscular differentiation and cytoskeletal formation in the tongue. Reduced cell proliferation in humans with IRF6 mutations may explain the wound-healing complications that follow cleft lip and palate repair in these patients.
This research was supported by grants from the National Institutes of Health (DE017953, HL097195, HL086324, DK078640, HL086964, HL092551, HL105334, DE013413, DK058404, GM058008, GM103391).