Phenotypes associated with this allele

• Allele Symbol: Atoh1⁺
• Allele Name: wild type
• Allele ID: MGI:2433372
• Summary: 4 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
cn1	Atoh1^tm3Hzo/Atoh1^+ Gt(ROSA)26Sor^tm1(cre/ERT)Nat/Gt(ROSA)26Sor^tm1(Smo/EYFP)Amc	involves: 129 * 129S7/SvEvBrd * 129X1/SvJ	MGI:4420943
cn2	Atoh1^tm4.1Hzo/Atoh1^+ Piezo2^tm2.2Apat/Piezo2^tm2.2Apat Tg(KRT14-cre)1Amc/0	involves: 129S7/SvEvBrd * C57BL/6 * CBA	MGI:5577087
cx3	Atoh1^tm2Hzo/Atoh1^+ Tcf4^tm1Zhu/Tcf4^+	involves: 129P2/OlaHsd	MGI:3776856
cx4	Atoh1^tm2Hzo/Atoh1^+ Gfi1^tm1Sho/Gfi1^tm1Sho	involves: 129S1/Sv * C57BL/6J	MGI:3696821

Genotype
MGI:4420943

cn1

• Allelic Composition: Atoh1^tm3Hzo/Atoh1⁺; Gt(ROSA)26Sor^{tm1(cre/ERT)Nat}/Gt(ROSA)26Sor^{tm1(Smo/EYFP)Amc}
• Genetic Background: involves: 129 * 129S7/SvEvBrd * 129X1/SvJ

• ♀: phenotype observed in females
• ♂: phenotype observed in males
• N: normal phenotype

nervous system

abnormal neuronal precursor proliferation ( J:155047 )

• ectopic masses show numerous mitotic granule neuron precursors 10 days after tamoxifen treatment

abnormal cerebellum morphology ( J:155047 )

• 10 days after tamoxifen treatment, neoplastic and preneoplastic lesions in which the external granule layer lacks the normal layered structure develop in the external layer of the cerebellum

abnormal cerebellum external granule cell layer morphology ( J:155047 )

• hypertrophic 10 days after tamoxifen treatment

irregular external granule cell layer thickness ( J:155047 )

• 10 days after tamoxifen treatment, neoplastic and preneoplastic lesions in which the external granule layer lacks the normal layered structure develop in the external layer of the cerebellum

cellular

abnormal neuronal precursor proliferation ( J:155047 )

• ectopic masses show numerous mitotic granule neuron precursors 10 days after tamoxifen treatment

Genotype
MGI:5577087

cn2

• Allelic Composition: Atoh1^tm4.1Hzo/Atoh1⁺; Piezo2^tm2.2Apat/Piezo2^tm2.2Apat; Tg(KRT14-cre)1Amc/0
• Genetic Background: involves: 129S7/SvEvBrd * C57BL/6 * CBA

behavior/neurological

abnormal mechanical nociception ( J:211312 )

• upon mechanical stimulation of Merkel cells, mutant cells do not display mechanically-activated currents but wild-type cells show a robust response

• sustained depolarization seen in wild-type cells upon injection of current is absent in Piezo2-deficient Merkel cells

• in an automated von Frey filament test, mutants show decreased percent withdrawal responses at lower forces only with similar responses at higher forces

nervous system

abnormal nervous system electrophysiology ( J:211312 )

• firing frequencies of slowly adapting ABeta fibers at various frequencies are reduced, and conduction velocities is reduced in ex vivo skin-saphenous nerve ending recordings

• touch dome afferents display short reduced firing compare to wild-type cells; firing patterns are intermediately adapting compared to maintained firing of wild-type touch dome afferents such that spikes fired and overall firing rates are significantly reduced

Genotype
MGI:3776856

cx3

• Allelic Composition: Atoh1^tm2Hzo/Atoh1⁺; Tcf4^tm1Zhu/Tcf4⁺
• Genetic Background: involves: 129P2/OlaHsd

mortality/aging

neonatal lethality ( J:125313 )

• mice die within the first 24 hours of birth but no embryonic lethality is observed as previously noted

nervous system

abnormal brain development ( J:125313 )

• the pontine nuclei is disrupted

Genotype
MGI:3696821

cx4

• Allelic Composition: Atoh1^tm2Hzo/Atoh1⁺; Gfi1^tm1Sho/Gfi1^tm1Sho
• Genetic Background: involves: 129S1/Sv * C57BL/6J

hearing/vestibular/ear

abnormal cochlear hair cell morphology ( J:80025 )

• at E15.5, the characteristic rows of IHCs and OHCs are not as clearly defined in the basal cochlea

• at E17.5, mutants display disorganization of hair cells and decreased hair cell numbers in the basal cochlea

• at P0, the apical cochlea shows little to no hair cell loss, but exhibits a disorganization similar to that seen in basal cochlea at E15.5

cochlear hair cell degeneration ( J:80025 )

• cochlear IHCs and OHCs are initially specified by E15.5 but are subsequently lost in a basal-to-apical gradient at P0

• by P3, the basal cochlea has few hair cells while the medial cochlea still retains most IHCs but has lost almost all OHCs

• in all cases, OHCs in a given region degenerate prior to IHCs cells

abnormal vestibular hair cell morphology ( J:80025 )

• at P0, the saccule shows disorganization of the hair cell layer, with some hair cells found in the supporting cell layer

• in contrast, cristae exhibit a relatively normal development of hair cells

abnormal vestibular hair cell stereociliary bundle morphology ( J:80025 )

• at P0, mutant vestibular hair cells appear to have less well organized stereocillia relative to wild-type hair cells

nervous system

abnormal cochlear hair cell morphology ( J:80025 )

• at E15.5, the characteristic rows of IHCs and OHCs are not as clearly defined in the basal cochlea

• at E17.5, mutants display disorganization of hair cells and decreased hair cell numbers in the basal cochlea

• at P0, the apical cochlea shows little to no hair cell loss, but exhibits a disorganization similar to that seen in basal cochlea at E15.5

cochlear hair cell degeneration ( J:80025 )

• cochlear IHCs and OHCs are initially specified by E15.5 but are subsequently lost in a basal-to-apical gradient at P0

• by P3, the basal cochlea has few hair cells while the medial cochlea still retains most IHCs but has lost almost all OHCs

• in all cases, OHCs in a given region degenerate prior to IHCs cells

abnormal vestibular hair cell morphology ( J:80025 )

• at P0, the saccule shows disorganization of the hair cell layer, with some hair cells found in the supporting cell layer

• in contrast, cristae exhibit a relatively normal development of hair cells

abnormal vestibular hair cell stereociliary bundle morphology ( J:80025 )

• at P0, mutant vestibular hair cells appear to have less well organized stereocillia relative to wild-type hair cells