title: Itm2a expression in the developing mouse first lower molar, and the subcellular localization of Itm2a in mouse dental epithelial cells.
abstract: Itm2a is a type II transmembrane protein with a BRICHOS domain. We investigated the temporospatial mRNA and protein expression patterns of Itm2a in the developing lower first molar, and examined the subcellular localization of Itm2a in murine dental epithelial (mDE6) cells. From the initiation to the bud stage, the in situ and protein signals of Itm2a were not detected in either the dental epithelial or mesenchymal cells surrounding the tooth bud. However, at the bell stage, these signals of Itm2a were primarily observed in the inner enamel epithelium of the enamel organ. After the initiation of the matrix formation, strong signals were detected in ameloblasts and odontoblasts. Itm2a showed a punctate pattern in the cytoplasm of the mDE6 cells. The perinuclear-localized Itm2a displayed a frequent overlap with the Golgi apparatus marker, GM130. A tiny amount of Itm2a was colocalized with lysosomes and endoplasmic reticulum. Minimal or no overlap between the Itm2a-EGFP signals with the other organelle markers for endoplasmic reticulum, lysosome and mitochondria used in this study noted in the cytoplasm. These findings suggest that Itm2a may play a role in cell differentiation during odontogenesis, rather than during the initiation of tooth germ formation, and may be related to the targeting of proteins associated with enamel and dentin matrices in the secretory pathway.
authors: Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan; Section of Orthodontics and Dentofacial Orthopedics, Division of Oral Health, Growth and Development, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Makiko
authors: M
authors: Kihara
authors: Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Tamotsu
authors: T
authors: Kiyoshima
authors: Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Kengo
authors: K
authors: Nagata
authors: Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Hiroko
authors: H
authors: Wada
authors: Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Hiroaki
authors: H
authors: Fujiwara
authors: Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan; Department of Endodontology and Operative Dentistry, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Kana
authors: K
authors: Hasegawa
authors: Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan; Section of Implant and Rehabilitative Dentistry, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Hirotaka
authors: H
authors: Someya
authors: Section of Orthodontics and Dentofacial Orthopedics, Division of Oral Health, Growth and Development, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Ichiro
authors: I
authors: Takahashi
authors: Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka, Japan.
authors: Hidetaka
authors: H
authors: Sakai
mesh_terms: D000565:Ameloblasts / Q000378:metabolism*; D000818:Animals; D002460:Cell Line; D004848:Epithelium / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D018507:Gene Expression Regulation, Developmental; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008807:Mice, Inbred BALB C; D008963:Molar / Q000166:cytology / Q000378:metabolism*; D009928:Organ Specificity; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014083:Tooth Germ / Q000378:metabolism
chemical_list: C117398:Itm2a protein, mouse; D008565:Membrane Proteins; D012333:RNA, Messenger