Hearing loss, caused by the death of hair cells in the inner ear, is the third most common public health issue in the United States. Currently, there are no therapeutic strategies to restore hearing. In her thesis research, Dr. Amrita A. Iyer investigated the possibility of regenerating functional hair cells by reprogramming non-hair cells of the mouse inner ear. She found that overexpression of a single transcription factor, ATOH1, can successfully reprogram non-sensory cells into hair cells with typical characteristics in neonatal mice. However, a combination of three transcription factors - ATOH1, GFI1, and POU4F3 - was required to reprogram inner hair cells in 1-week old mice. Her findings provide a window into the developmental and gene expression requirements for regeneration of inner ear hair cells in mammals, and may inform future therapeutic strategies for hearing loss in humans.