酿酒酵母Snf1/AMPK蛋白激酶通过调节细胞壁合成相关基因的表达影响细胞壁完整性

Snf1/AMPK affects cell wall integrity through regulating the transcription of cell wall assembly-related genes in Saccharomyces cerevisiae

【目的】初步探讨酿酒酵母(Saccharomyces cerevisiae)中Snf1/AMPK蛋白激酶影响细胞壁完整性的机制。【方法】通过同源重组交换的方法,构建酿酒酵母Snf1/AMPK蛋白激酶催化亚基的敲除菌株snf1Δ,并通过基因回补对敲除菌株表型进行验证。在含有刚果红(Congo red)和荧光增白剂(Calcofluor white)的平板上检测snf1Δ菌株细胞壁的完整性,通过q RT-PCR的方法检测snf1Δ菌株中已知的细胞壁合成相关基因的表达情况。【结果】SNF1基因敲除影响细胞壁的完整性,并影响酿酒酵母对热激应答的反应。进一步研究发现,SNF1突变菌株中β-1,3-葡聚糖合成相关基因与β-1,6-葡聚糖合成相关基因的表达量均明显降低。【结论】结果显示酿酒酵母Snf1蛋白激酶影响细胞壁的完整性,此影响发生在转录水平上,即通过调节细胞壁合成相关基因的转录来实现,揭示了Snf1蛋白的一个新角色。

[Objective] To study the role of Snf1/AMPK kinase in cell wall integrity in Saccharomyces cerevisiae JY102.[Methods] SNF1 deletion mutant of S.cerevisiae was created by homologous recombination.Congo red and Calcofluor white were applied to evaluate the cell wall integrity for the mutant strain.q RT-PCR was used to analyze the transcription of cell wall-related genes.[Results] The SNF1 disruption mutant was severely sensitive to Congo red and Calcofluor white,manifesting the impairment of cell wall integrity.The mutant exhibited apparently growth defect at high temperature.The results of q RT-PCR revealed down-regulated transcription of several genes involved in β-glucan biosynthesis.[Conclusion] The deletion of Snf1 impairs the cell wall integrity by reducing the transcription of β-glucan-related genes,suggesting a new role of Snf1 in the activation of cell wall synthesis.