title: Localization of Beclin1 in mouse developing tooth germs: possible implication of the interrelation between autophagy and apoptosis.
abstract: Our previous study identified the appearance of autophagy in developing tooth germs, and suggested its possible association with apoptosis in odontogenesis. Beclin1 was recently indicated to play a central role in bridging autophagy and apoptosis, and occupied a key position in the process of development. This study hypothesized that Beclin1 may be involved, and act as the molecular basis of the connection between autophagy and apoptosis in odontogenesis. Immunohistochemical analysis showed the spatiotemporal expression pattern of Beclin1 in odontogenesis from embryonic (E) day 13.5 to postnatal (P) day 5.5. At E stages, Beclin1 was mainly immunolocalized in the cytoplasm of the cells in the enamel organ. Meanwhile, the nucleus localization of Beclin1 was detected in part of the stellate reticulum, outer and inner enamel epithelium, especially at E16.5 and E18.5. At P stages, Beclin1 was detected in the cytoplasm of the odontoblasts, besides the dental epithelium cells. Triple immunofluorescence analysis showed the partial colocalization of Beclin1, autophagic marker LC3, or activated caspase-3 in the E14.5 tooth germs, especially the Beclin1(+)LC3(+)Caspase-3(+) cells in the PEK. Furthermore, western blot analysis revealed that the full-length (60 kDa) and/or cleaved (50, 37, and 35 kDa) Beclin1 in the developing tooth germs. Taken together, our findings indicate that Beclin1 is involved, and might be responsible for the crosstalk between autophagy and apoptosis in mouse odontogenesis.
authors.affiliation: The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), Key Laboratory of Oral, Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, 237 Luoyu Road, Wuhan, 430079, People's Republic of China.
authors.forename: Jingwen
authors.initials: J
authors.lastname: Yang
authors.forename: Chunyan
authors.initials: C
authors.lastname: Wan
authors.forename: Shuai
authors.initials: S
authors.lastname: Nie
authors.forename: Shujuan
authors.initials: S
authors.lastname: Jian
authors.forename: Zheyi
authors.initials: Z
authors.lastname: Sun
authors.forename: Lu
authors.initials: L
authors.lastname: Zhang
authors.forename: Zhi
authors.initials: Z
authors.lastname: Chen
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000235:genetics; D051017:Apoptosis Regulatory Proteins / Q000235:genetics / Q000378:metabolism*; D001343:Autophagy / Q000235:genetics; D000071186:Beclin-1; D053148:Caspase 3 / Q000378:metabolism; D015870:Gene Expression; D007150:Immunohistochemistry; D051379:Mice; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008963:Molar / Q000196:embryology / Q000378:metabolism; D009805:Odontogenesis / Q000235:genetics; D011485:Protein Binding; D021381:Protein Transport; D014083:Tooth Germ / Q000196:embryology* / Q000378:metabolism*
chemical_list: D051017:Apoptosis Regulatory Proteins; D000071186:Beclin-1; C115010:Becn1 protein, mouse; C480860:Map1lc3b protein, mouse; D008869:Microtubule-Associated Proteins; D053148:Caspase 3