title: Adenomatous polyposis coli (APC) is required for normal development of skin and thymus.
abstract: The tumor suppressor gene Apc (adenomatous polyposis coli) is a member of the Wnt signaling pathway that is involved in development and tumorigenesis. Heterozygous knockout mice for Apc have a tumor predisposition phenotype and homozygosity leads to embryonic lethality. To understand the role of Apc in development we generated a floxed allele. These mice were mated with a strain carrying Cre recombinase under the control of the human Keratin 14 (K14) promoter, which is active in basal cells of epidermis and other stratified epithelia. Mice homozygous for the floxed allele that also carry the K14-cre transgene were viable but had stunted growth and died before weaning. Histological and immunochemical examinations revealed that K14-cre-mediated Apc loss resulted in aberrant growth in many ectodermally derived squamous epithelia, including hair follicles, teeth, and oral and corneal epithelia. In addition, squamous metaplasia was observed in various epithelial-derived tissues, including the thymus. The aberrant growth of hair follicles and other appendages as well as the thymic abnormalities in K14-cre; Apc(CKO/CKO) mice suggest the Apc gene is crucial in embryonic cells to specify epithelial cell fates in organs that require epithelial-mesenchymal interactions for their development.
authors.affiliation: Harvard-Partners Center for Genetics and Genomics, Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Mari
authors.initials: M
authors.lastname: Kuraguchi
authors.forename: Xiu-Ping
authors.initials: XP
authors.lastname: Wang
authors.forename: Roderick T
authors.initials: RT
authors.lastname: Bronson
authors.forename: Rebecca
authors.initials: R
authors.lastname: Rothenberg
authors.forename: Nana Yaw
authors.initials: NY
authors.lastname: Ohene-Baah
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Lund
authors.forename: Melanie
authors.initials: M
authors.lastname: Kucherlapati
authors.forename: Richard L
authors.initials: RL
authors.lastname: Maas
authors.forename: Raju
authors.initials: R
authors.lastname: Kucherlapati
mesh_terms: D025601:Adenomatous Polyposis Coli Protein / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D000483:Alleles; D000818:Animals; D020964:Embryo Loss; D004622:Embryo, Mammalian / Q000002:abnormalities; D005786:Gene Expression Regulation; D005838:Genotype; D018859:Hair Follicle / Q000166:cytology / Q000473:pathology; D053823:Hedgehog Proteins / Q000235:genetics; D006801:Humans; D007633:Keratins / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008819:Mice, Nude; D008969:Molecular Sequence Data; D009928:Organ Specificity; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012867:Skin / Q000196:embryology / Q000254:growth & development*; D013950:Thymus Gland / Q000196:embryology / Q000254:growth & development*; D014070:Tooth / Q000166:cytology / Q000473:pathology; D051176:beta Catenin / Q000235:genetics
chemical_list: D025601:Adenomatous Polyposis Coli Protein; D053823:Hedgehog Proteins; D012333:RNA, Messenger; C465570:Shh protein, mouse; D051176:beta Catenin; D007633:Keratins