A novel transcriptional activation mechanism of inulinase gene in Kluyveromyces marxianus involving a glycolysis regulator KmGcr1p with unique and functional Q-rich repeats,Molecular Microbiology

当前位置： X-MOL 学术 › Mol. Microbiol. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

A novel transcriptional activation mechanism of inulinase gene in Kluyveromyces marxianus involving a glycolysis regulator KmGcr1p with unique and functional Q-rich repeats
Molecular Microbiology ( IF 2.6 ) Pub Date : 2022-02-25 , DOI: 10.1111/mmi.14889
Fengyi Li ₁ , Mengqi Wang ₁ , Zhe Chi _{1,

2} , Zhaoxuan Zhang ₁ , Xiaoxiang Wang ₁ , Mengdan Xing ₁ , Zhenming Chi _{1,

2,

3} , Guanglei Liu _{1,

2,

3}

Affiliation

Kluyveromyces marxianus is the most suitable fungus for inulinase industrial production. However, the underlying transcriptional activation mechanism of the inulinase gene (INU1) is hitherto unclear. Here, we undertook genetic and biochemical analyses to elucidate that a glycolysis regulator KmGcr1p with unique Q-rich repeats is the key transcriptional activator of INU1. We determined that INU1 and glycolytic genes share similar transcriptional activation patterns and that inulinase activity is induced by fermentable carbon sources including the hydrolysis products of inulin (fructose and glucose), which suggests a novel model of product feedback activation. Furthermore, all four CT-boxes in the INU1 promoter are important for KmGcr1p DNA-binding in vitro, but the most downstream CT-box 1 primarily confers upstream activating sequence activity in vivo. More intriguingly, the use of artificial and natural GCR1 mutants suggests that the Q-rich repeats act as a functional module to maintain KmGcr1p transcriptional activity by contributing to its solubility and DNA-binding affinity. Altogether, this study uncovers a novel transcriptional activation mechanism for the inulinase gene, that is different from the previous understanding for filamentous fungi, but might have universal significance among inulinase-producing yeasts, thereby leading to a better understanding of the regulation mechanism of yeast inulinase genes.

中文翻译：

马克斯克鲁维酵母菊粉酶基因的一种新转录激活机制，涉及糖酵解调节因子 KmGcr1p，具有独特且功能性的 Q-rich 重复序列

马克斯克鲁维酵母是最适合菊粉酶工业化生产的菌类。然而，菊粉酶基因 ( INU1 ) 的潜在转录激活机制迄今仍不清楚。在这里，我们进行了遗传和生化分析，以阐明具有独特 Q 丰富重复序列的糖酵解调节因子 KmGcr1p 是INU1的关键转录激活因子。我们确定INU1和糖酵解基因具有相似的转录激活模式，并且菊粉酶活性是由包括菊粉水解产物（果糖和葡萄糖）在内的可发酵碳源诱导的，这表明了一种新的产物反馈激活模型。此外， INU1中的所有四个 CT 盒启动子对体外 KmGcr1p DNA 结合很重要，但最下游的 CT-box 1 主要赋予体内上游激活序列活性。更有趣的是，人工和天然GCR1突变体的使用表明，富含 Q 的重复序列作为一个功能模块，通过促进其溶解度和 DNA 结合亲和力来维持 KmGcr1p 转录活性。总之，本研究揭示了一种新的菊粉酶基因转录激活机制，不同于以往对丝状真菌的理解，但可能在生产菊粉酶的酵母中具有普遍意义，从而更好地理解酵母菊粉酶的调控机制。基因。

更新日期：2022-02-25

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11