gene is deleted, but mice bred to be missing the gene grow more hair cells than control mice that have the gene. Additionally, the sonic hedgehog protein has been shown to block activity of the retinoblastoma protein, thereby inducing cell cycle re-entry and the regrowth of new cells. Several Notch signaling pathway inhibitors, including the gamma secretase inhibitor LY3056480, are being studied for their potential ability to regenerate hair cells in the cochlea. TBX2 (T-box transcription factor 2) has been shown to be a master regulator in the differentiation of inner and outer hair cells. This discovery has allowed researchers to direct hair cells to develop into either inner or outer hair cells, which could help in replacing hair cells that have died and prevent or reverse hearing loss. The cell cycle inhibitor p27kip1 (CDKN1B) has also been found to encourage regrowth of cochlear hair cells in mice following genetic deletion or knock down with siRNA targeting p27. Research on hair cell regeneration may bring us closer to clinical treatment for human hearing loss caused by hair cell damage or death. Additional images References Bibliography External links Molecular Basis of Hearing Outer hair cell dancing "rock around the clock" Dancing OHC video Yale Ear Lab NIF Search – Hair Cell via the Neuroscience Information Framework Hair-Tuning-Sound-Sensor A concise report on the recent development of sound sensors based on hair tuning by students of SMMEE, IIT Ropar Auditory system Receptor cells Human cells