目的:研究葡萄糖、甘露糖、半乳糖对新生隐球菌荚膜相关基因CAP10启动活性的影响。方法:用含CAP10编码区上游5’侧翼序列(-951~0bp)和报告基因的重组体转化酵母,分别用不同浓度(10、20、40、60、80mg/ml)的葡萄糖、甘露糖、半乳糖对其进行干预,用ELISA方法检测CAT表达值,比较各组间CAT表达活性的不同。结果:不同浓度的葡萄糖和甘露糖对CAT的表达强弱无明显的影响;而不同浓度的半乳糖对CAT的表达强弱有明显的影响,而且这种正向诱导作用在实验所用的剂量范围内具有剂量依赖关系。结论:葡萄糖和甘露糖对CAP10启动活性无明显影响;半乳糖对CAP10的启动活性有明显的诱导作用,推测CAP10基因可能与新生隐球菌中半乳糖的代谢有关。
Objective:To study the effects of glucose, mannose and galactose on CAP10 promoter activity of Cryptococcus neoforrnans capsule-associated gene. Methods: Yeast cells were transfected with plasmid containing a 951 bp length of 5' upstream flanking sequence of CAP10 coding region and a reporter gene, chloramphenicol acetyl transferase (CAT) ; the transfectants were treated with different concentrations( 10,20,40,60,80 mg/ml) of glucose, mannose and galactose. CAT activity was assessed by ELISA method and CAT activities of different groups were compared. Results: Different concentrations of glucose and mannose had no obvious influence on CAT activity; different concentrations of galactose had obvious influence on CAT activity and the influence was positively dependent with its dose within the experimental concentration range. Conclusion: Glucose and mannose have no obvious effect on the activity of CAP10 promoter; galactose has obvious inductive effect on activity of CAP10 promoter, suggesting that CAP10 gene might be related with galactose metabolism.