All Phenotypes Lhx3<tm1Lmgd> MGI Mouse

prenatal lethality, complete penetrance ( J:33050 )

• homozygotes are still born or die within the first 24 hours after birth

• those born alive are able to breath and so no obvious cause for death

adrenal cortical hyperplasia ( J:33050 )

abnormal corticotroph morphology ( J:33050 )

• corticotroph cell lineage present but fails to proliferate

decreased gonadotroph cell number ( J:33050 )

• no LH-expressing cells could be detected in the pituitary primordia at E18.5, suggesting an absence or at least a severely reduced number of gonadotrophs

absent lactotrophs ( J:33050 )

absent somatotrophs ( J:33050 )

• anterior pituitary expression of GH was absent at E16.5, indicating an absence of somatotrophs

absent thyrotrophs ( J:33050 )

• anterior pituitary expression of TSHbeta was absent at E16.5, indicating an absence of thyrotrophs

absent adenohypophysis ( J:33050 , J:51420 )

abnormal pituitary gland development ( J:33050 )

• homozygotes lack the anterior and intermediate lobes of the pituitary gland

• however, the posterior lobe is grossly normal

abnormal Rathke's pouch development ( J:33050 )

• Rathke's pouch is normal at E10.5 but fails to develop further

• at E10.5, the opening of Rathke's pouch to the oral cavity is wider than normal and the epithelial cells lining the pouch are multilayered and less columnar

• at E12.5 and E15.5, the wall of the pouch remains a thin layer of epithelium and retains a narrow connection to the oral cavity

• arrest of growth and differentiation is due to a proliferation failure rather than increased apoptosis

absent pituitary intermediate lobe ( J:33050 , J:51420 )

nervous system phenotype ( J:51420 )

N	• motor neuron development is normal