Phenotypes associated with this allele

• Allele Symbol: Nr2f1^tm1Mist
• Allele Name: targeted mutation 1, Michele Studer
• Allele ID: MGI:3521756
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Nr2f1^tm1Mist/Nr2f1^tm1Mist	involves: 129S2/SvPas * C57BL/6J	MGI:3688750
ht2	Nr2f1^tm1Mist/Nr2f1^+	B6.129S2-Nr2f1^tm1Mist/Cnrm	MGI:8253351

Genotype
MGI:3688750

hm1

• Allelic Composition: Nr2f1^tm1Mist/Nr2f1^tm1Mist
• Genetic Background: involves: 129S2/SvPas * C57BL/6J

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

mortality/aging

perinatal lethality, complete penetrance ( J:114098 )

• all homozygotes die at perinatal stages

nervous system

abnormal brain commissure morphology ( J:114098 )

• corpus callosum and hippocampal commissure are stunted at midline

abnormal corpus callosum morphology ( J:114098 )

• at E18.5, callosal projections in mutants fail to show decussation in most fetuses

• non-crossing commissural fibers have an abnormal defasciculated appearance

• at all levels, callosal projections form aberrantly oriented Probst bundles

• mutants fail to show segregation of anterior versus posterior projections

abnormal hippocampal commissure morphology ( J:114098 )

• failure of hippocampal commissure to cross midline is observed and ventrally oriented ectopic thick bundles are seen

• all hippocampal fibers form a thick bundle together with the fornix which shows aberrant growth into the septal region

abnormal anterior commissure morphology ( J:114098 )

• number of anterior limb branches of the anterior commissure (AC) in the olfactory cortex is increased

• anterior and posterior branching are abnormally positioned dorsoventrally; innervation of anteromedial cortex by these branches is through numerous tracts

• some AC fascicles show aberrant connections with hippocampal commissure

abnormal cerebral cortex morphology ( J:114098 )

• embryos present a significantly extended length of medial cortex compared with dorsoventral length of the telencephalon

abnormal cingulate gyrus morphology ( J:114098 )

• embryos present a ventrally extended cingulate cortex

abnormal neuron morphology ( J:114098 )

• cultured hippocampal neurons from mutants have no protrusions or a slightly elongated process after 12 hours

• when normal neurons show a symmetrical distribution of neurites, mutant neurons have no processes or abnormal neurites that tended to curl up on themselves

abnormal axon guidance ( J:114098 )

• all major forebrain commissures have guidance abnormalities along anterior-posterior and dorsoventral axesin mutants

abnormal axon morphology ( J:114098 )

• cultured neurons display numerous short filopodial extensions and growth cone-like structures around the cell body and neurites; axons roll up in an abnormal fashion

• Map1b protein levels in growing axons are decreased significantly

cellular

abnormal axon guidance ( J:114098 )

• all major forebrain commissures have guidance abnormalities along anterior-posterior and dorsoventral axesin mutants

Genotype
MGI:8253351

ht2

• Allelic Composition: Nr2f1^tm1Mist/Nr2f1⁺
• Genetic Background: B6.129S2-Nr2f1^tm1Mist/Cnrm

growth/size/body

decreased body weight ( J:373120 )

♂ • males, but not females, show a decrease in body weight at P100

♂ • however, body weight is normal at P4, P8, P12, P20, and P30

behavior/neurological

behavior/neurological phenotype ( J:373120 )

N • mice do not show alterations during the social interaction test, no abnormalities in the dark-light box test or in the hole board test, no changes in anxiety or exploratory behavior, and alternations in the active place avoidance test

abnormal locomotor coordination ( J:373120 )

• increase in front paw width, however the width between the hind paws is normal

• the proportion of time the ipsilateral forelimb and hindlimb remain in contact with the walkway is reduced, however diagonal and girdle support are not altered and no significant step sequence changes are seen

abnormal vocalization ( J:373120 )

• the proportion of complex calls is reduced at P4 and P8

decreased vocalization ( J:373120 )

• pups show a reduction in the number of ultrasonic vocalizations at P4, with the number of calls reduced by 30%

• mice exhibit reduced average call duration at P4 and P8

• however, by P8 and P12, no differences in call frequency are seen

nervous system

decreased corpus callosum size ( J:373120 )

• mice show corpus callosum thinning at P28, with a 17% reduction