Date of Defense
Date of Graduation
Specialization and development of the vertebrate ear occurred in order for there to be differences between the cochlea and the vestibular system in mammals. It has been previously shown that early deletion of Gata3 in the inner ear of mice results in abnormal development of inner ear neurosensory epithelia. However, Gata3 expression begins in the otocyst and spans from early embryogenesis through adulthood. To better understand the function of Gata3 at later postnatal time points we conditionally knocked out Gata3 when hair cells are just starting to differentiate utilizing the Atoh1-cre mouse line, and shortly after differentiation of the inner hair cells utilizing the Fgf8-cre mouse line. Absence of Gata3 at the time of hair cell differentiation results in a disorganized arrangement of hair cells, in the middle and apical regions while the basal region appears normal. While the hair cells appear disorganized, the organization of supporting cells appear normal. However, the organization and orientation of the stereocilia appears vestibular like. Knocking out Gata3 later in hair cell differentiation results in a similar, but less severe pattern of hair cell disorganization and a more prominent vestibular stereocilia of the inner hair cells.
Blinkiewicz, Paige, "Changes in the Gata3 Gene Regulatory Network Was Necessary for the Evolution of Mammalian Hearing" (2019). Honors Theses. 3202.