Phenotypes associated with this allele

• Allele Symbol: Isl1^tm2Sev
• Allele Name: targeted mutation 2, Sylvia M Evans
• Allele ID: MGI:3817457
• Summary: 3 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
cn1	Isl1^tm1(cre/Esr1*)Krc/Isl1^tm2Sev	involves: 129 * 129S1/Sv * 129X1/SvJ * C57BL/6	MGI:3817491
cn2	Gt(ROSA)26Sor^tm1Sor/Gt(ROSA)26Sor^+ Isl1^tm2Sev/Isl1^tm2Sev H2az2^Tg(Wnt1-cre)11Rth/H2az2^+	involves: 129S1/Sv * 129X1/SvJ * C57BL/6 * CBA	MGI:3817490
cn3	Isl1^tm2Sev/Isl1^tm2.1Sev Tg(Hoxb6-cre)#Mku/0	involves: 129S1/Sv * 129X1/SvJ * FVB/N	MGI:5320482

Genotype
MGI:3817491

cn1

• Allelic Composition: Isl1^{tm1(cre/Esr1*)Krc}/Isl1^tm2Sev
• Genetic Background: involves: 129 * 129S1/Sv * 129X1/SvJ * C57BL/6

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

mortality/aging

perinatal lethality, complete penetrance ( J:141110 )

• induction of cre-recombinase expression at E11.5 leads to death of the animal during the perinatal period

nervous system

abnormal sensory neuron morphology ( J:141110 )

• the number of neurons expressing TrpVI and TrpM8 are markedly decreased in the dorsal root ganglion of E18.5 embryos that have had cre-recombinase induced at E11.5

Genotype
MGI:3817490

cn2

• Allelic Composition: Gt(ROSA)26Sor^tm1Sor/Gt(ROSA)26Sor⁺; Isl1^tm2Sev/Isl1^tm2Sev; H2az2^{Tg(Wnt1-cre)11Rth}/H2az2⁺
• Genetic Background: involves: 129S1/Sv * 129X1/SvJ * C57BL/6 * CBA

mortality/aging

neonatal lethality, complete penetrance ( J:141110 )

• mice die within a few hours of birth

nervous system

abnormal sensory neuron innervation pattern ( J:141110 )

• cutaneous branch of the ventral ramus is absent in E14.5 embryos

• innervation of the distal limbs at E14.5 confirmed a nearly complete loss of fine cutaneous sensory fibers with only a single sensory branch innervating one side of digits 1, 2 and 5 in both the forelimb and hindlimb

abnormal trigeminal ganglion morphology ( J:141110 )

• there is an increased rate of apoptosis within the trigeminal ganglia of E11.5 and E12.5 embryos

abnormal dorsal root ganglion morphology ( J:141110 )

• the dorsal root ganglion (DRG) of E12.5 embryos do not express Isl1 protein

• TrkA⁺ neurons are lower in number starting at E12.5 and by E14.5 are less than one-third of what is found in controls

• TrkB⁺ neurons are also lower in number starting at E12.5 and are markedly reduced at E14.5 and birth

• TrkC⁺ neurons do not appear until E12.5, a delay of two days compared to controls

dorsal root ganglion hypoplasia ( J:141110 )

• the DRG of E14.5 embryos is markedly smaller than controls with a smaller number neurons found within the ganglion

• an increased rate of apoptosis is noted in the E12.5 DRG

behavior/neurological

decreased chemical nociceptive threshold ( J:141110 )

• mice have a reduced response to a mild noxious stimulus that was applied to the skin of the trunk or limbs

Genotype
MGI:5320482

cn3

• Allelic Composition: Isl1^tm2Sev/Isl1^tm2.1Sev; Tg(Hoxb6-cre)#Mku/0
• Genetic Background: involves: 129S1/Sv * 129X1/SvJ * FVB/N

limbs/digits/tail

abnormal hindlimb bud morphology ( J:184018 )

• expression analysis indicates proximal patterning defects in the hindlimb buds

hindlimb oligodactyly ( J:184018 )

• variable severity of hindlimb digit loss

• almost half of mice display hindlimbs with only 3 digits

• less severely affected mice develop 4 hindlimb digits, lacking the posterior digit 5

abnormal hindlimb zeugopod morphology ( J:184018 )

• only a single zeugopodal element, likely corresponding to the tibia, is present in most mice with 1 - 3 digits on the hindlimb

• mice with 4 digits on the hindlimb show more variability in zeugopodal defects

absent hindlimb ( J:184018 )

• in severely affected mice

embryo

abnormal hindlimb bud morphology ( J:184018 )

• expression analysis indicates proximal patterning defects in the hindlimb buds

skeleton

abnormal ischium morphology ( J:184018 )

• patterning failure

absent pubis ( J:184018 )

• patterning failure