title: Over-expression of thymosin beta 4 promotes abnormal tooth development and stimulation of hair growth.
abstract: Thymosin beta 4 has multi-functional roles in cell physiology. It accelerates wound healing, hair growth and angiogenesis, and increases laminin-5 expression in corneal epithelium. Furthermore, thymosin beta 4 stimulates tumor growth and metastasis by induction of cell migration and vascular endothelial growth factor-mediated angiogenesis. Using a construct on the skin-specific keratin-5 promoter, we have developed thymosin beta 4 over-expressing transgenic mice to further study its functional roles. Thymosin beta 4 in adult skin and in embryonic stages of the transgenic mouse was analyzed by both Western blot and immunohistochemistry. The over-expression of thymosin beta 4 was observed especially around hair follicles and in the teeth in the transgenic mice. We examined the phenotype of the thymosin beta 4 over-expressing mice. Hair growth was accelerated. In addition, the transgenic mice had abnormally-shaped white teeth and dull incisors. We found that the expression of laminin-5 was up-regulated in the skin of the transgenic mice. We conclude that thymosin beta 4 has an important physiological role in hair growth and in tooth development.
authors.affiliation: Department of Parasitology and Genetics, College of Medicine, Kosin University, Busan, South Korea. hcha@kosin.ac.kr
authors.forename: Hee-Jae
authors.initials: HJ
authors.lastname: Cha
authors.forename: Deborah
authors.initials: D
authors.lastname: Philp
authors.forename: Soo-Hyun
authors.initials: SH
authors.lastname: Lee
authors.forename: Hye-Sung
authors.initials: HS
authors.lastname: Moon
authors.forename: Hynda K
authors.initials: HK
authors.lastname: Kleinman
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakamura
mesh_terms: D000818:Animals; D005260:Female; D006197:Hair / Q000000981:diagnostic imaging / Q000187:drug effects / Q000254:growth & development*; D053555:Keratin-5 / Q000235:genetics; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011859:Radiography; D013947:Thymosin / Q000235:genetics / Q000378:metabolism*; D014070:Tooth / Q000000981:diagnostic imaging / Q000254:growth & development*; D014071:Tooth Abnormalities / Q000378:metabolism* / Q000473:pathology; D000099201:Thymosin beta(4)
chemical_list: D053555:Keratin-5; D008840:Microfilament Proteins; D013947:Thymosin; D000099201:Thymosin beta(4)