Architecture of the Inner Ear

Normal hearing is dependent upon a highly specialized structure in the inner ear called the tectorial membrane. How this precisely organized extracellular matrix is assembled had been unknown. However, Park and colleagues showed the inner ear membrane anchors to the cell surface during development and grows one layer at a time. This process depends upon anchoring and then release of the GPI-anchored protein TECTA. Once a layer is formed, TECTA is released, and the next layer is ‘printed' underneath it. The mechanism is similar to 3D printing and eventually results in a multi-layered architecture. This proposed 3D printing model provides novel insight into our understanding of the extracellular matrix morphogenesis process during development and tissue repair.