title: Genetic deletion of the EGFR ligand epigen does not affect mouse embryonic development and tissue homeostasis.
abstract: The epidermal growth factor receptor (EGFR) is a tyrosine kinase receptor with manifold functions during development, tissue homeostasis and disease. EGFR activation, the formation of homodimers or heterodimers (with the related ERBB2-4 receptors) and downstream signaling is initiated by the binding of a family of structurally related growth factors, the EGFR ligands. Genetic deletion experiments clarified the biological function of all family members except for the last characterized ligand, epigen. We employed gene targeting in mouse embryonic stem cells to generate mice lacking epigen expression. Loss of epigen did not affect mouse development, fertility, or organ physiology. Quantitative RT-PCR analysis revealed increased expression of betacellulin and EGF in a few organs of epigen-deficient mice, suggesting a functional compensation by these ligands. In conclusion, we completed the genetic analysis of EGFR ligands and show that epigen has non-essential functions or functions that can be compensated by other EGFR ligands during growth and tissue homeostasis.
authors.affiliation: Institute of Molecular Animal Breeding and Biotechnology, Gene Center, LMU Munich, Feodor-Lynen-Str. 25, 81377 Munich, Germany.
authors.forename: Maik
authors.initials: M
authors.lastname: Dahlhoff
authors.forename: Matthias
authors.initials: M
authors.lastname: Schäfer
authors.forename: Eckhard
authors.initials: E
authors.lastname: Wolf
authors.forename: Marlon R
authors.initials: MR
authors.lastname: Schneider
mesh_terms: D000825:Animal Structures / Q000196:embryology / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D047108:Embryonic Development / Q000235:genetics*; D004815:Epidermal Growth Factor / Q000235:genetics*; D066261:Epigen; D066246:ErbB Receptors / Q000378:metabolism; D005260:Female; D017353:Gene Deletion; D006706:Homeostasis / Q000235:genetics*; D008024:Ligands; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010641:Phenotype; D011247:Pregnancy
chemical_list: C587855:Epgn protein, mouse; D066261:Epigen; D008024:Ligands; D004815:Epidermal Growth Factor; C541485:EGFR protein, mouse; D066246:ErbB Receptors