title: The immunohistochemical localization of signal-transduction pathway components Jak1, Jak2, Jak3, Tyk2 and STAT-1 during early enamel and dentine formation in rat molars.
abstract: This study sought to localize immunohistochemically Janus kinase (Jak) and Tyk isoforms and STAT-1 in association with events involved in early dentine and enamel formation in the rat molar. The Jaks and STATs (signal transducers and activators of transcription) are key signal-transduction pathway components in the cytokine receptor-linked pathway. The histological sections were not demineralized or fixed, providing optimum conditions for immunohistochemical localization. It appears that all of the Jak isoforms and STAT-1 are involved in enamel formation. Jak2 and STAT-1 colocalized in the proximal ends of presecretory and secretory-stage ameloblasts, supporting work by others that growth hormone receptor is located at that site. The colocalization of Jak1, Jak2 and STAT-1 along the proximal ends of presecretory and secretory ameloblasts suggests that the interferon receptor is up-regulated in these cells as well. Also, colocalization of Jak3 and STAT-1 in the proximal ends of the ameloblasts and the cells of the stratum intermedium predicts the location of the interleukin-7 receptor in those locations. Jak1, Tyk2 and STAT-1, but not Jak2 or Jak3, stain was seen in the odontoblasts.
authors.affiliation: Department of Pediatric Dentistry, University of North Carolina, Chapel Hill 27599, USA.
authors.forename: S
authors.initials: S
authors.lastname: Tanase
authors.forename: J W
authors.initials: JW
authors.lastname: Bawden
mesh_terms: D000565:Ameloblasts / Q000201:enzymology*; D000566:Amelogenesis / Q000502:physiology*; D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D016207:Cytokines / Q000502:physiology; D004268:DNA-Binding Proteins / Q000032:analysis / Q000378:metabolism; D003810:Dentinogenesis / Q000502:physiology*; D007150:Immunohistochemistry; D053613:Janus Kinase 1; D053614:Janus Kinase 2; D053616:Janus Kinase 3; D009804:Odontoblasts / Q000201:enzymology*; D011505:Protein-Tyrosine Kinases / Q000032:analysis / Q000378:metabolism*; D011506:Proteins / Q000032:analysis / Q000378:metabolism; D011518:Proto-Oncogene Proteins; D051381:Rats; D017207:Rats, Sprague-Dawley; D017471:Receptors, Interferon / Q000378:metabolism; D018123:Receptors, Interleukin / Q000378:metabolism; D020395:Receptors, Interleukin-7; D011986:Receptors, Somatotropin / Q000378:metabolism; D050794:STAT1 Transcription Factor; D015398:Signal Transduction; D053634:TYK2 Kinase; D015534:Trans-Activators / Q000032:analysis / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D015703:Antigens, CD; D016207:Cytokines; D004268:DNA-Binding Proteins; C507936:Jak3 protein, rat; D011506:Proteins; D011518:Proto-Oncogene Proteins; D017471:Receptors, Interferon; D018123:Receptors, Interleukin; D020395:Receptors, Interleukin-7; D011986:Receptors, Somatotropin; D050794:STAT1 Transcription Factor; C494081:Stat1 protein, rat; D015534:Trans-Activators; D014157:Transcription Factors; D011505:Protein-Tyrosine Kinases; C507906:Jak1 protein, rat; C507927:Jak2 protein, rat; D053613:Janus Kinase 1; D053614:Janus Kinase 2; D053616:Janus Kinase 3; D053634:TYK2 Kinase; C499357:Tyk2 protein, rat