Analysis Tools
growth/size/body
|
• mutants have normal molar crowns but reduced roots
|
|
• mature individuals are only one fourth the weight of their normal sibs
• reduced size begins after 14th day
|
skeleton
|
• mutants have normal molar crowns but reduced roots
|
hearing/vestibular/ear
|
• the repeated pattern of outer hair cells in P14 and P25 mutants is disrupted
• mean surface area of outer hair cells is reduced by about 15%
|
|
• the orientation of the outer hair cell bundles in P14 and P25 mutants is disrupted
|
|
• mice exhibit a small fraction of outer hair cell degeneration by P42 along the cochlea, although most outer hair cells survive
• the most prominent hair cell loss is in the lower apical region
|
|
• outer hair cells are about 24% shorter than in wild-type mice
|
|
• the tectorial membrane has a more prominent Hensen's stripe that persists through P42
|
|
• organization of the cytoskeleton is abnormal in pillar cells at P25 which persists through P42
|
|
• delay in the opening of the tunnel of Corti at P12, but by P21, the opening is indistinguishable from wild-type mice
|
|
• stria is smaller in width at P21 and P42, due to reduced contribution of intermediate cells
• abnormalities in the stria vascularis are more obvious at P42 than at P12 or P21
• stria vascularis shows less interdigitation of the intermediate cells with the basal aspect of the marginal cells and less infolding of the basolateral membrane
• accumulation of dark lipofuscin-like deposits in the stria vacularis of P42 old mutants
|
|
• deterioration of the intermediate cells
|
|
• the tectorial membrane contains an abnormal protrusion at P21 which appears to be a more prominent Hensens stripe that persists through P42
|
|
• abnormalities in the structure of the striated-sheet matrix in the tectorial membrane
|
|
• 50% and 45% reduction in endocochlear potential in 3 and 6 week old mice, respectively
|
|
• mutant outer hair cells have varying mixtures of low- and high-voltage activated conductances compared to wild-type cells which have a dominant low-voltage activated KCNQ4 current and a reduction in KCNQ4 currents
|
|
• adult mutants lack cochlear microphonics, indicating compromised outer hair cell function
• lack of a cochlear microphonics response is indicated by the absence of a frequency-dependent phase shift
|
|
• adult mutants lack DPOAE, indicating compromised outer hair cell function
|
pigmentation
|
• deterioration of the intermediate cells
|
reproductive system
infertility
(
J:13120
)
|
• both males and females are entirely sterile
|
homeostasis/metabolism
|
• GH was undetectable from birth to 6 weeks of age
|
|
• PRL was undetectable from birth to 6 weeks of age
|
|
• minimal concentrations of PRL were detected in the plasma
|
endocrine/exocrine glands
|
• PRL-producing mammotropes were absent
|
|
• GH-producing somatotropes were absent
|
|
• almost complete absence of TSH-producing thyrotroph
|
nervous system
|
• PRL-producing mammotropes were absent
|
|
• GH-producing somatotropes were absent
|
|
• almost complete absence of TSH-producing thyrotroph
|
|
• the repeated pattern of outer hair cells in P14 and P25 mutants is disrupted
• mean surface area of outer hair cells is reduced by about 15%
|
|
• the orientation of the outer hair cell bundles in P14 and P25 mutants is disrupted
|
|
• mice exhibit a small fraction of outer hair cell degeneration by P42 along the cochlea, although most outer hair cells survive
• the most prominent hair cell loss is in the lower apical region
|
|
• outer hair cells are about 24% shorter than in wild-type mice
|
|
• mutant outer hair cells have varying mixtures of low- and high-voltage activated conductances compared to wild-type cells which have a dominant low-voltage activated KCNQ4 current and a reduction in KCNQ4 currents
|
|
• adult mutants lack cochlear microphonics, indicating compromised outer hair cell function
• lack of a cochlear microphonics response is indicated by the absence of a frequency-dependent phase shift
|
craniofacial
|
• mutants have normal molar crowns but reduced roots
|
cellular
|
• organization of the actin cytoskeleton is abnormal in pillar cells at P25 through P42, as shown by FITC-phalloidin staining
|
