title: Effect of 1,25-dihydroxyvitamin D3on spontaneous calcium responses in rat dental epithelial SF2 cells revealed by long-term imaging.
abstract: Genetically encoded calcium indicators (GECIs) are suitable for long-term imaging studies. In this study, we employed a highly sensitive GECI, G-GECO, and achieved efficient gene delivery with an adenoviral vector. The adenoviral vector allowed us to express G-GECO in more than 80% of cells. More than 80% of G-GECO-expressing cells showed an ATP-induced increase in fluorescence intensity due to Ca2+release from intracellular stores and subsequent Ca2+entry. The fluorescence intensity of these cells was increased more than 2-fold by stimulation with 10 μM ATP. We applied long-term imaging (for ~10 h) to monitor Ca2+responses in SF2, a rat dental epithelial cell line, in culture conditions. SF2 cells showed intermittent rises in the intracellular Ca2+concentration in the presence of 100 nM 1,25-dihydroxyvitamin D3. Many of these Ca2+responses began at a specific location in the cytoplasm and spread throughout the entire cytoplasm. The combination of efficient gene delivery with an adenoviral vector and long-term imaging with a highly sensitive GECI enabled detection of intermittent Ca2+responses that occur only 3-10 times/h/100 cells. This method could be useful to study the effects of Ca2+responses for regulating longterm processes, such as gene expression, cell migration, and cell division, in many cell types.
authors.affiliation: Department of Pediatric Dentistry, School of Dentistry, Health Sciences University of Hokkaido.
authors.forename: Kaori
authors.initials: K
authors.lastname: Murata
authors.forename: Ayumi
authors.initials: A
authors.lastname: Takahashi
authors.forename: Takao
authors.initials: T
authors.lastname: Morita
authors.forename: Akihiro
authors.initials: A
authors.lastname: Nezu
authors.forename: Satoshi
authors.initials: S
authors.lastname: Fukumoto
authors.forename: Masato
authors.initials: M
authors.lastname: Saitoh
authors.forename: Akihiro
authors.initials: A
authors.lastname: Tanimura
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling / Q000187:drug effects*; D002460:Cell Line; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism*; D015870:Gene Expression; D017930:Genes, Reporter; D006801:Humans; D057054:Molecular Imaging; D051381:Rats; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D014807:Vitamin D; C097949:1,25-dihydroxyvitamin D; D002118:Calcium