Phenotypes for Arx MGI:2451237 MGI Mouse

neonatal lethality, complete penetrance ( J:79871 )

• male hemizygotes are born at normal Mendelian ratios at E19.5 but die within 12 hrs after birth

• at E13.5, hemizygotes exhibit a nearly normal migration of neuroepithelial cells in the cortical plate, except for some projection neurons

• at E14.5, hemizygotes display loss of direct migration of interneurons from the medial ganglionic eminence to the cortical intermediate zone

• in contrast, the migration of interneurons from the medial ganglionic eminence to the cortical subventricular zone via the lateral ganglionic eminence appears unchanged

abnormal forebrain development ( J:79871 )

• hemizygotes display abnormalities in neuronal proliferation, interneuronal migration and differentiation of the embryonic forebrain

abnormal hippocampus development ( J:79871 )

• at E19.5, hemizygotes exhibit dysgenesis of the hippocampus

abnormal telencephalon development ( J:79871 )

abnormal cortical marginal zone morphology ( J:79871 )

• at E19.5, only a small number of neurons of detected in the marginal zone

abnormal cortical plate morphology ( J:79871 )

• in hemizygotes, glutaminergic neurons are abnormally distributed in layers II-V of the cortical plate instead of being located in layer V as in wild-type mice

thin cortical plate ( J:79871 )

• at E19.5, the cortical plate is thinner than normal

decreased cortical ventricular zone thickness ( J:79871 )

• at E12.5 and E14.5, the neocortical ventricular zone is thinner and contains fewer BrdU-positive cells than in wild-type mice

decreased brain size ( J:79871 )

• hemizygotes have small brains

enlarged third ventricle ( J:79871 )

• at E19.5, the third ventricle is expanded due to partial dysgenesis of the thalamus

abnormal brain internal capsule morphology ( J:79871 )

• at E18.5, thalamocortical axons to the internal capsule appear elongated via an ectopic pathway located in the vicinity of the amygdala

abnormal thalamus morphology ( J:79871 )

• at E12.5, hemizygotes display a deficiency in the thalamic eminence and part of the ventral thalamus

• as a result, the anterior medial thalamic nuclei and most of the central medial thalamic nuclei are lost at E19.5

abnormal central medial nucleus morphology ( J:79871 )

• at E19.5, most of the central medial thalamic nuclei are lost

abnormal telencephalon morphology ( J:79871 )

• at E19.5, hemizygotes display morphological abnormalities in the dorsal and ventral telencephalon

abnormal hippocampus CA3 region morphology ( J:79871 )

• at E19.5, hemizygotes display dysgenesis of the CA3 field

abnormal dentate gyrus morphology ( J:79871 )

• at E19.5, hemizygotes display dysgenesis of the dentate gyrus

absent hippocampal fimbria ( J:79871 )

• at E19.5, the hippocampal fimbria are lost

abnormal neocortex morphology ( J:79871 )

• at E14.5, the embryonic neocortex is thinner than normal as a result of reduced proliferation of neuroepithelial cells in the entire neocortical ventricular zone

abnormal olfactory bulb morphology ( J:79871 )

• the left and right olfactory bulbs are positioned with a wide interspace

small olfactory bulb ( J:79871 )

• hemizygotes have small olfactory bulbs

abnormal nervous system tract morphology ( J:79871 )

• at E18.5, hemizygotes display many aberrant nerve fiber tracts, including the passage of thalamocortical axons through the amygdala

abnormal corpus callosum morphology ( J:79871 )

• at E19.5, the corpus callosum appears abnormal with a shortened anterioposterior axis

absent hippocampal commissure ( J:79871 )

• at E19.5, the hippocampal commissure is lost

abnormal glutaminergic neuron morphology ( J:79871 )

• in hemizygotes, glutaminergic neurons are abnormally distributed in layers II-V of the cortical plate instead of being located in layer V as in wild-type mice

seminal vesicle hypoplasia ( J:79871 )

• hemizygotes display hypoplasia of the seminal vesicles

enlarged seminiferous tubules ( J:79871 )

• hemizygotes display seminiferous tubules of increased diameter relative to wild-type mice

abnormal fetal Leydig cell differentiation ( J:79871 )

• at E14.5, expression of the Leydig cell marker Hsd3b1 is severely reduced in the interstitial region of mutant testes, indicating a block in Leydig cell differentiation

• this effect is variable among individual mutant mice

small testis ( J:79871 )

• hemizygotes have small testes