Loss of transcription factor AP-2gamma/TFAP2C impairs branching morphogenesis of the murine mammary gland

Dev Dyn. 2010 Mar;239(3):1027-33. doi: 10.1002/dvdy.22239.


Extensive development of the mammary gland occurs during puberty, when rising levels of ovarian hormones induce the formation of highly proliferative terminal end buds (TEBs) at the tips of mammary ducts. TEBs consist of an outer layer of cap cells and of inner body cells. TEBs invade the adipose stroma and bifurcate while extending the ducts to generate an arborized ductal network. We show that in murine mammary glands transcription factor AP-2gamma is strongly expressed in the cap cell layer and in a subset of body cells of TEBs. To decipher AP-2gamma functions during mammary development we generated AP-2gamma-deficient mice. Their mammary glands displayed impaired ductal branching and elongation. Cellular proliferation within TEBs was reduced. Although estrogen receptor was expressed, exogenously administered ovarian hormones could not restore normal development. Therefore, AP-2gamma is functionally involved in branching morphogenesis of the mammary epithelium, possibly by controlling genetic processes downstream of ovarian hormones.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Proliferation
  • Female
  • Gene Expression Regulation, Developmental*
  • Genotype
  • Mammary Glands, Animal / growth & development*
  • Mammary Glands, Animal / metabolism*
  • Mice
  • Mice, Knockout
  • Mice, Transgenic
  • Morphogenesis*
  • Ovary / growth & development*
  • Ovary / metabolism
  • Phenotype
  • Receptors, Estrogen / metabolism
  • Transcription Factor AP-2 / biosynthesis*
  • Transcription Factors / metabolism


  • Receptors, Estrogen
  • Transcription Factor AP-2
  • Transcription Factors