title: The C-terminal domain of the adenomatous polyposis coli (Apc) protein is involved in thyroid morphogenesis and function.
abstract: Adenomatous polyposis coli (APC) is a multifunctional protein as well as a tumor suppressor. To determine the functions of the C-terminal domain of Apc, we have investigated Apc                         (                            1638T/1638T                         ) mice, which express a truncated Apc that lacks the C-terminal domain. Apc                         (                            1638T/1638T                         ) mice are tumor free and exhibit growth retardation. In the present study, we analyzed the morphology and functions of the thyroid gland in Apc                         (                            1638T/1638T                         ) mice. There was no significant difference in the basal concentration of serum thyroid hormones between Apc                         (                            1638T/1638T                         ) and Apc                         (+/+) mice. Thyroid follicle size was significantly larger in Apc                         (                            1638T/1638T                         ) mice than in Apc                         (+/+) mice. The extent of serum T4 elevation following exogenous thyroid-stimulating hormone (TSH) injection was lower in Apc                         (                            1638T/1638T                         ) mice than in Apc                         (+/+) mice. TSH also induced a greater reduction in thyroid follicle size in Apc                         (                            1638T/1638T                         ) mice than in Apc                         (+/+) mice. Analyses using immunohistochemistry and electron microscopy indicated that follicular epithelial cells in Apc                         (                            1638T/1638T                         ) mice had an enlarged rough endoplasmic reticulum of irregular shape. These results suggest that the C-terminal domain of Apc is involved in thyroid morphology and function.
authors.affiliation: Department of Anatomy I, Fujita Health University School of Medicine, Toyoake, Aichi, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Yokoyama
authors.forename: Ryuji
authors.initials: R
authors.lastname: Nomura
authors.forename: Masafumi
authors.initials: M
authors.lastname: Kurosumi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Shimomura
authors.forename: Takanori
authors.initials: T
authors.lastname: Onouchi
authors.forename: Akiko
authors.initials: A
authors.lastname: Iizuka-Kogo
authors.forename: Ron
authors.initials: R
authors.lastname: Smits
authors.forename: Naohisa
authors.initials: N
authors.lastname: Oda
authors.forename: Riccardo
authors.initials: R
authors.lastname: Fodde
authors.forename: Mitsuyasu
authors.initials: M
authors.lastname: Itoh
authors.forename: Takao
authors.initials: T
authors.lastname: Senda
mesh_terms: D025601:Adenomatous Polyposis Coli Protein / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000818:Animals; D020869:Gene Expression Profiling; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009024:Morphogenesis; D010446:Peptide Fragments / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion; D013961:Thyroid Gland / Q000254:growth & development* / Q000378:metabolism / Q000648:ultrastructure; D013972:Thyrotropin / Q000494:pharmacology / Q000502:physiology; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
chemical_list: D025601:Adenomatous Polyposis Coli Protein; D010446:Peptide Fragments; D011994:Recombinant Proteins; D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine