3-磷酸甘油醛对酵母孢子萌发的抑制作用分析  

Analysis of inhibitory effect of 3-glyceraldehyde phosphate in yeast spore germination

作　　者：成卓 刘国玉 中西秀树[1] CHENG Zhuo;LIU Guoyu;NAKANISHI Hideki(School of Biotechnology,Jiangnan University,Wuxi 214122,China;China National Research Institute of Food and Fermentation Industries Co.Ltd.,Beijing Key Laboratory of the Innovative Development of Functional Staple and Nutritional Intervention for Chronic Diseases,Beijing 100015,China)

机构地区：[1]江南大学生物工程学院,江苏无锡214122 [2]中国食品发酵工业研究院有限公司,功能主食创制与慢病营养干预北京市重点实验室,北京100015

出　　处：《食品与发酵工业》2025年第4期42-48,共7页Food and Fermentation Industries

基　　金：国家自然科学基金(32071467)。

摘　　要：在酿酒酵母孢子中,存在糖酵解产物3-磷酸甘油醛(3-glyceraldehyde phosphate,GAP)参与的抑制萌发的负调节机制,但是目前的调控途径并不完善。该研究目的是发现GAP对萌发孢子的影响,并深入了解其负调控机制。重点分析以GAP为底物的糖酵解酶——三磷酸甘油醛脱氢酶(glyceraldehyde-3-phosphate dehydrogenase,GAPDH)在调控机制中的作用。该文采用富营养培养基和热处理等多种条件诱导酵母孢子萌发,并通过荧光增白剂染色来测定萌发率。分别在有无GAP的条件下诱导萌发,研究GAPDH的表达水平。接着利用qPCR的方法检验GAPDH mRNA的表达水平。此外,在酵母中敲除TDH1、TDH2和TDH3这3个GAPDH的结构基因,分析突变体的萌发效率。结果显示当营养物诱导或加热处理促使孢子萌发时,GAPDH的表达水平显著降低,而在孢子萌发的过程中添加GAP反而会增加GAPDH水平。qPCR结果显示孢子萌发时GAPDH的mRNA水平没有降低,故GAPDH表达水平的降低是因为在萌发过程中蛋白被降解。且GAPDH单个结构基因的缺失会增加孢子的萌发率。结果表明GAPDH参与GAP介导的负调控机制。Spores exit a quiescent state and start mitotic growth when they encounter sufficient nutrients.This process is called germination.In Saccharomyces cerevisiae spores,there is a negative regulatory mechanism which inhibits germination.A glycolytic product 3-glyceraldehyde phosphate(GAP)is known to be involved in the negative regulatory mechanism and spore germination is inhibited in the presence of GAP.However,the entire process of the regulatory mechanism remains elusive.The objectives of this study were to find the effects of GAP on germinating spores and to gain insight into the mechanism of the negative regulatory mechanism.In particular,the role of glyceraldehyde triphosphate dehydrogenase(GAPDH),which was a glycolytic enzyme using GAP as a substrate,in the regulatory mechanism was analysed.Yeast spore germination was induced by various conditions including nutrient-rich media and by heat-treatment.Germination efficiency can be assayed by calcofluor whit staining.Expression levels of GAPDH was investigated when germination was induced in the presence or absence of GAP.In yeast,there are three structural genes of GAPDH,TDH1,TDH2,and TDH3.These genes were disrupted and germination efficiencies of these mutants were analysed.Expression levels of GAPDH were significantly reduced when germination was induced either by nutrients or heat.However,GAPDH levels were increased by the addition of GAP even if spores were incubated in nutrient-rich media.Since levels of GAPDH mRNAs were not decreased,GAPDH proteins were likely degraded during germination.Germination efficiencies were increased when these genes,especially,TDH2 and TDH3,were deleted.GAPDH is known as a multifunction protein and regulates various processes.Results suggest that GAPDH is involved in the negative regulatory mechanism,possibly as a downstream regulator of GAP.

关 键 词：静止期细胞 酵母 三磷酸甘油醛脱氢酶 孢子 萌发 

分 类 号：TS261.11[轻工技术与工程—发酵工程]