Phenotypes for Foxi1 MGI:3056282 MGI Mouse

abnormal inner ear morphology ( J:82307 )

inner ear cyst ( J:82307 )

• homozygotes display cystic dilatation of the inner ears at E18.5

abnormal cochlea morphology ( J:82307 )

• at E16.5, the basal turn of the cochlea is larger while the apical turn has formed an apical cyst

absent cochlear modiolus ( J:82307 )

abnormal common crus morphology ( J:82307 )

• at E16.5, homozygotes show a prominent expansion of the common crus

dilated lateral semicircular canal ( J:82307 )

• at E16.5, homozygotes show a prominent expansion of the lateral semicircular canal

dilated posterior semicircular canal ( J:82307 )

• at E16.5, homozygotes show a prominent expansion of the posterior semicircular canal, common crus and ampullae

abnormal membranous labyrinth morphology ( J:82307 )

• at E16.5, the entire membranous labyrinth appears enlarged; no major aberrations are observed up to E13.5

enlarged utricle ( J:82307 )

• at E16.5, the mutant utricle is significantly enlarged relative to wild-type

enlarged vestibular saccule ( J:82307 )

• at E16.5, the mutant saccule is significantly enlarged relative to wild-type

dilated endolymphatic duct ( J:82307 )

• at E16.5, homozygotes exhibit a pronounced expansion of the endolymphatic compartment

• by P12, the peri- and endolymphatic compartments of the inner ear have been replaced by a common irregular cavity

dilated endolymphatic sac ( J:82307 )

• at E16.5, homozygotes exhibit a severe dilatation of the endolymphatic sac

absent otoliths ( J:82307 )

• homozygotes show complete absence of the normally white utricular and saccular otoconia found in wild-type, suggesting defective crystallization of calcium carbonate crystals

absent endocochlear potential ( J:82307 )

• homozygotes lack an endocochlear potential indicating a primary defect in fluid homeostasis in the inner ear

deafness ( J:82307 )

• homozygotes are deaf

abnormal temporal bone morphology ( J:82307 )

• the mutant temporal bone is thinner adjacent to the inner ear relative to wild-type

• at E18.5, homozygotes show abnormal integration of the otic capsule into the temporal bone anlagen associated with ectopic cartilage and/or bone formation

increased apoptosis ( J:82307 )

• at E16.5, homozygotes show a minor increase of apoptosis in a small mesenchymal cell population adjacent to the expanded endolymphatic duct

abnormal cerebellum morphology ( J:82307 )

• the mutant cerebellum appears compressed due to the severe expansion of the inner ear

renal tubular acidosis ( J:90907 )

• homozygotes fail to secrete protons in response to both a chronic as well as an acute acidic load

• homozygotes are unable to acidify the urine and display a reduced systemic buffer capacity

• homozygotes develop renal tubular acidosis in response to a prolonged acidic load

increased urine pH ( J:90907 )

• homozygotes produce urine with elevated pH relative to wild-type

abnormal kidney collecting duct epithelium morphology ( J:90907 )

• homozygotes show ultrastructural changes in the epithelium of the cortical collecting duct (CCD)

• mitochondria-rich cells with a protruding "tussock-like" apex are missing from mutants CCDs

• the distal nephron epithelium with its two major cell types (principal and intercalated cells) is replaced by a single cell type positive for both principal and intercalated cell markers