title: ATF-2 immunoreactivity in post-mitotic and terminally differentiated human odontoblasts.
abstract: Activating transcription factor 2 (ATF-2/CRE-BP1; cAMP-responsive element binding protein 1) is a member of nuclear transcription factor activator protein-1 (AP-1) family. AP-1 regulates cellular processes including growth, proliferation, differentiation and apoptosis. However, biological relationship of cellular process to each member of the AP-1 family is not clear yet. The objective of the present study was to compare the ATF-2 immunoreactivity in the post-mitotic and terminally differentiated odontoblasts and in the pulpal fibroblasts which can be divided by mitosis when required. Fibroblasts at various stages of differentiation co-exist in the human dental pulp. ATF-2 was investigated immunohistochemically in 20 permanent human teeth. According to the findings obtained, the mean percentage of ATF-2 positive cells was 68.5 ± 19.2% in the odontoblasts and 22.8 ± 13.7% in the pulpal fibroblasts. The comparison of ATF-2 positivity revealed a statistically significant difference between odontoblasts and pulpal fibroblasts. These findings have suggested that ATF-2 is more associated with cell survival rather than cell proliferation, and revealed much of effectiveness in maintaining terminal differentiation than the various differentiation stages of the cells.
authors.affiliation: Division of Basic Sciences, Department of Histology and Embryology, Faculty of Dentistry, Istanbul University, Capa, Istanbul, Turkey. nkeklik@istanbul.edu.tr.
authors.forename: Nurullah
authors.initials: N
authors.lastname: Keklikoglu
authors.affiliation: Division of Basic Sciences, Department of Histology and Embryology, Faculty of Dentistry, Istanbul University, Capa, Istanbul, Turkey.
authors.forename: Sevtap
authors.initials: S
authors.lastname: Akinci
mesh_terms: D051698:Activating Transcription Factor 2 / Q000032:analysis*; D000328:Adult; D002454:Cell Differentiation; D002470:Cell Survival; D003782:Dental Pulp / Q000166:cytology*; D019229:Dentition, Permanent; D005260:Female; D005347:Fibroblasts / Q000737:chemistry* / Q000502:physiology; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009804:Odontoblasts / Q000737:chemistry* / Q000502:physiology; D055815:Young Adult
chemical_list: C497105:ATF2 protein, human; D051698:Activating Transcription Factor 2
keywords: AP-1; ATF-2; Dental pulp; Differentiation; Fibroblast; Odontoblast; Proliferation