Fig. 3. Expression profile of markers in Gfi1 mutant ears. (A,C,E,G,I,K) Gfi1 wild type (+/+); (B,D,F,H,J,L) Gfi1 null (-/-) mice. The inner hair cell is denoted by a red arrow and the outer hair cells by green arrows. (A-F) Anti-myosin VI/VIIa (Myo) staining of inner ear hair cells showing abnormal cell shape (arrow) and organization (arrowhead) at E13.5 (A,B) and E14.5 (C,D) in the developing vestibular organs. Note that some mutant hair cells are maintained in the support cell layer (arrowhead). (E,F) Hair cells in the mutant organ of Corti are disorganized. (G,H) Math1 in situ showing that mRNA expression in the organ of Corti at E17.5 is unaffected in the mutants, but hair cells are disorganized. (I,J) Brn3c in situ showing Brn3c mRNA expression in the organ of Corti at E18.5 is unaffected in the mutant, but the hair cells are disorganized. (K,L) Anti-TUJ1 staining marking the neurons at E17.5 showing abnormal TUJ1 staining in the outer hair cells of the mutant. Note that in wild type, innervation stops at the base of the outer hair cells, but the TUJ1 staining of the mutant outer hair cells appears to be all over the cell body. The inner hair cell is indicated by a red arrow and the outer hair cells by green arrows.