title: Osmosensitive gene expression of taurine transporter and cyclin C in embryonic fibroblast cells.
abstract: Hypertonic conditions induce osmoregulatory activity. Molecular mechanism, however, remains to be further elucidated concerning the osmosensitive balancing activity. Using a differential display protocol, the genes of taurine transporter (TauT) and cyclin C were identified as candidate responding to the hypertonicity. When a quantitative PCR analysis was performed on the total RNA from KBEF cell treated under hypertonic conditions, the gene expressions of TauT and cyclin C were greatly increased. In terms of protein, the level of TauT expression increased up to 3.2-fold in response to the hypertonic treatment. Similarly to TauT, cyclin C protein also increased 2.4-fold compared to the control treatments. Under taurine-rich extracellular conditions, however, the level of TauT expression increased as little as 1.8-fold by hypertonicity treatment. Cyclin C expression was also lowered compared with low-taurine hypertonic treatment. Cysteine dioxygenase was shown to be highly responsive to the hypertonic treatment. Taken together, these results strongly indicate that the gene expressions of TauT and cyclin C are cooperatively regulated under hypotonic conditions.
authors.affiliation: University of Ulsan College of Medicine, Korea.
authors.forename: Changkyu
authors.initials: C
authors.lastname: Oh
authors.forename: Yun Jaie
authors.initials: YJ
authors.lastname: Choi
authors.forename: Hyung Gee
authors.initials: HG
authors.lastname: Kim
authors.forename: Dong-Hee
authors.initials: DH
authors.lastname: Lee
mesh_terms: D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D016213:Cyclins / Q000235:genetics / Q000378:metabolism*; D004622:Embryo, Mammalian / Q000166:cytology* / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology / Q000502:physiology*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006801:Humans; D006982:Hypertonic Solutions; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D009994:Osmolar Concentration; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D013654:Taurine / Q000378:metabolism; D000099247:Taurine Transporters
chemical_list: D016213:Cyclins; D006982:Hypertonic Solutions; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger; D013654:Taurine; D000099247:Taurine Transporters