Consequences of the dual origin of the middle ear epithelium on function

The mammalian middle ear is an air-filled space, lined with an epithelium, that houses three small bones called ossicles, which conduct sound from the eardrum to the inner ear. Previously, it was thought that the lining of the middle ear was entirely endoderm-derived. However, Dr Tucker's recent work shows that the lining has a dual origin, as part of the middle ear is lined with neural crest cells that undergo a mesenchymal-to-epithelial transformation. She now aims to understand the normal development of the middle ear – and how defects during development have an impact on the function of the ear – by identifying the signals involved in this mesenchymal-to-epithelial transformation. In addition, she wishes to understand the consequence of the dual origin of the epithelium on susceptibility to ear infection (otitis media) and the development of middle-ear cysts (cholesteatomas), both major problems in the middle ear.