The role of intracellular Cl‐ concentration in cell proliferation

• Published in: The FASEB journal 2006-03, Vol.20 (5), p.A1460-A1460
• Main Authors: Shiozaki, Atsushi, Miyazaki, Hiroaki, Niisato, Naomi, Itoi, Hirosumi, Yamagishi, Hisakazu, Marunaka, Yoshinori
• Format: Article
• Language: English
• ISSN: 0892-6638; 1530-6860
• DOI: 10.1096/fasebj.20.5.A1460-b

Modulation of ion permeability during the cell cycle is one of the key events in cell cycle progression. Our recent study indicates that intracellular Cl− concentration ([Cl−]i) could act as a signal to regulate ion channel mRNA expression in renal epithelial A6 cells (AJP 287:F932‐9, 2004). This result suggests that the changes of [Cl−]i is one of the important candidates to cell proliferation. In the present study, we studied whether [Cl−]i regulates cell proliferation in A6 cells. Treatment with low Cl− (about 15 mM) medium (replacement of NaCl by NaNO3) for 72 h induce a significant decrease of [Cl−]i associated with reduction of cell growth rate compared with control (normal Cl− medium). Using flow cytometrical analysis, we found that cell cycle arrest occurred at the G0/G1 phase in low Cl−‐treated cells. These data indicate that [Cl−]i plays important roles in cell proliferation and cell cycle transition through the G1/S checkpoint. This work was supported by Grants‐in‐Aid from JSPS (17390057, 17590191, 17790154).