Yao Shumin, Chi Zhenming, He Susu
UNESCO Chinese Center of Marine Biotechnology, Ocean University of China, Yushan Road No.5, Qingdao, 266003, China.
Indian J Biochem Biophys. 2006 Jun;43(3):143-7.
In this study, the effects of inositol addition on maltase activity and expression of MAL1+ gene encoding maltase in Schizosaccharomyces pombe were investigated. The maximum specific maltase activity was observed, when the concentration of inositol reached 6.0 microg/ml in the synthetic medium containing 2.0% glucose. At 1.0 microg/ml inositol concentration, the maltase activity continuously decreased, as initial glucose concentration was higher than 0.1%. mRNA encoding maltase and phosphatidylinositol (PI) content were higher in the cells grown in the synthetic medium with 6.0 microg/ml of inositol and 2.0% glucose than those with 1.0 microg/ml of inositol. These results demonstrated that higher inositol concentration in the synthetic medium could derepress MAL1+ gene expression in S. pombe and PI might be involved in derepression of MAL1+ gene expression in S. pombe probably by PI-type signalling pathway.
本研究考察了添加肌醇对粟酒裂殖酵母中麦芽糖酶活性以及编码麦芽糖酶的MAL1⁺基因表达的影响。在含有2.0%葡萄糖的合成培养基中，当肌醇浓度达到6.0微克/毫升时，观察到最大比麦芽糖酶活性。当肌醇浓度为1.0微克/毫升时，随着初始葡萄糖浓度高于0.1%，麦芽糖酶活性持续下降。在含有6.0微克/毫升肌醇和2.0%葡萄糖的合成培养基中生长的细胞中，编码麦芽糖酶的mRNA和磷脂酰肌醇（PI）含量高于含有1.0微克/毫升肌醇的细胞。这些结果表明，合成培养基中较高的肌醇浓度可解除粟酒裂殖酵母中MAL1⁺基因的表达抑制，PI可能通过PI型信号通路参与粟酒裂殖酵母中MAL1⁺基因表达的解除抑制。
