The winged helix gene, Foxb1, controls development of mammary glands and regions of the CNS that regulate the milk-ejection reflex.
The ability to lactate is a process restricted to mammals and is necessary for the survival of nonhuman mammals. Female mice carrying a null mutation in the winged helix transcription factor Foxb1 (previously Mf3/Fkh5/TWH) have lactation defects on inbred genetic backgrounds. To determine the cellular basis of the Foxb1 lactation defect we have inserted a tau-lacZ lineage marker into the locus to follow the fate of Foxb1 expressing cells. This approach has revealed that Foxb1 is expressed in epithelial cells of developing and adult mammary glands as well as previously described regions of the central nervous system. Mammary glands from C57BL/6 Foxb1-/- mice have incomplete lobuloalveolar development. In addition, the tau-lacZ lineage label was used to determine that the mammillothalamic tract was lost in all Foxb1-/- mice. Finally, morphological defects in the inferior colliculi of the midbrain in Foxb1-/- mice correlate with the inability to lactate, suggesting that the midbrain defect, but not the loss of the mammillothalamic tract, may be responsible for the lactation defect.
Kloetzli
J M
JM
Department of Cell and Developmental Biology, University of Pennsylvania, Philadelphia 19104-6058, USA.
Fontaine-Glover
I A
IA
Brown
E R
ER
Kuo
M
M
Labosky
P A
PA
D000818:Animals; D001921:Brain / Q000196:embryology / Q000254:growth & development*; D003433:Crosses, Genetic; D004268:DNA-Binding Proteins / Q000235:genetics*; D005260:Female; D051858:Forkhead Transcription Factors; D018390:Gene Targeting / Q000379:methods*; D006579:Heterozygote; D006720:Homozygote; D007124:Immunoenzyme Techniques; D007763:Lac Operon / Q000502:physiology; D008297:Male; D008321:Mammary Glands, Animal / Q000196:embryology / Q000254:growth & development*; D008326:Mammillary Bodies / Q000254:growth & development*; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D008893:Milk Ejection / Q000502:physiology*; D010641:Phenotype; D012018:Reflex / Q000235:genetics; D013234:Stem Cells / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics*; D016875:tau Proteins / Q000378:metabolism
D004268:DNA-Binding Proteins; D051858:Forkhead Transcription Factors; C491332:Foxb1 protein, mouse; D014157:Transcription Factors; D016875:tau Proteins