beta-Catenin controls hair follicle morphogenesis and stem cell differentiation in the skin

Cell. 2001 May 18;105(4):533-45. doi: 10.1016/s0092-8674(01)00336-1.


beta-Catenin is an essential molecule in Wnt/wingless signaling, which controls decisive steps in embryogenesis. To study the role of beta-catenin in skin development, we introduced a conditional mutation of the gene in the epidermis and hair follicles using Cre/loxP technology. When beta-catenin is mutated during embryogenesis, formation of placodes that generate hair follicles is blocked. We show that beta-catenin is required genetically downstream of tabby/downless and upstream of bmp and shh in placode formation. If beta-catenin is deleted after hair follicles have formed, hair is completely lost after the first hair cycle. Further analysis demonstrates that beta-catenin is essential for fate decisions of skin stem cells: in the absence of beta-catenin, stem cells fail to differentiate into follicular keratinocytes, but instead adopt an epidermal fate.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Differentiation / physiology
  • Cell Lineage / physiology
  • Cytoskeletal Proteins / genetics*
  • Cytoskeletal Proteins / metabolism*
  • Gene Deletion
  • Gene Expression Regulation, Enzymologic
  • Hair Follicle / cytology*
  • Hair Follicle / embryology*
  • Integrases / genetics
  • Keratin-14
  • Keratinocytes / cytology
  • Keratinocytes / metabolism
  • Keratins / genetics
  • Mice
  • Mice, Knockout
  • Mutagenesis, Insertional / physiology
  • Phenotype
  • Stem Cells / cytology*
  • Stem Cells / metabolism
  • Trans-Activators*
  • Viral Proteins*
  • beta Catenin


  • CTNNB1 protein, mouse
  • Cytoskeletal Proteins
  • Keratin-14
  • Krt14 protein, mouse
  • Trans-Activators
  • Viral Proteins
  • beta Catenin
  • Keratins
  • Cre recombinase
  • Integrases