真菌Cercospora beticola的12种毒素贝第高林对癌基因ras转导的肾上腺细胞生长的作用

• 作者: Bernard F MAUME Claude HUMBERT Gabrielle MAUME Hanan OSMAN Jean-Pierre BLEIN Marie-Louise MILAT Martine PADIEU 丁国庆
• 来源期刊: 中国药理学报（英文版）
• 学科: 医学
• 关键词: 贝第高林 细胞分裂 转化细胞系 肾上腺皮质 钙 原癌基因蛋白质p21(ras) 共聚焦显微镜检查
• 年，卷（期）: 2001,（9）
• 所属期刊栏目: 研究原著
• 页码范围: 769-776
• 页数: 8页
• 分类号: R96
• 语种: 英文

摘要

AIM: To explore different effects of 12 beticolins, Cercospora beticola toxins, on ras-transformed adrenocortical cell growth inhibition and their functional mechanism.METHODS: Beticolin-induced inhibition was measured with survival cell number determined by an automated photocolorimetric method. The penetration of beticolin was examined by confocal microscopy. Ras protein determined by Lowry method were separated by 14 % SDS-PAGE and electroblotted to Immobilon-P transfer membrane and detected with pan-Ras (Ab-3) monoclonal antibody. The Ca2+ chelation by beticolin was investigated using a calcium ionophore. RESULTS: Cell growth inhibition was found dose- and time-dependently at submicromolar level for beticolin-1, -2, and -13 (IC50 ≤250 nmol/L) and for beticolin-0, 6, and-11 (400 nmol/L ＜ IC50 ≤ 500 nmol/L ). The inhibition by beticolin-1 was immediate, independent of cell culture step and not reversible for 3-day treatment. Beticolin-3 and -4 were slightly active (1 μmol/L ＜ IC50 ≤ 2μmol/L) and beticolin-7, -9, -12, and -5 were inactive at micromolar level. The beticolin-induced cell growth inhibition was correlated with the hydrophobicity of these compounds. Beticolin-1 fluorescence in RTAC cells was detected by confocal microscopy whereas beticolin-3 and -12 were not even after a 24 h incubation period.Beticolin-1-induced cell growth inhibition was partially reverted by calcium ionophore suggesting a role of intracellular Ca2 + chelation by beticolin-1 on cell growth inhibition. Furthermore, beticolin-1 blocked up Ras p21 translocation to membrane and induced accumulation of Ras in the cytosol as an inactive form by different ways.