Zhang Yu, Wu Yuanyuan, Yang Xulei, Yang En, Xu Huini, Chen Yuhui, Chagan Irbis, Yan Jinping
Laboratory of Bioconversion, Life Science and Technology College, Kunming University of Science and Technology, Kunming, 650500, PR China.
College of Life Science, the Southwest Forest University, Kunming, 650224, PR China.
Appl Environ Microbiol. 2021 Apr 15;87(8). doi: 10.1128/AEM.00055-21. Epub 2021 Feb 12.
White-rot fungi, especially strains, are the primary source of industrial laccases in bioenergy and bioremediation. strains express members of the laccase gene family with different physicochemical properties and expression patterns. However, the literature on the expression pattern of the laccase gene family in S0301 and the response mechanism to Cu, a key laccase inducer, in white-rot fungal strains is scarce. In the present study, we found that Cu could induce the mRNAs and proteins of the two alternative splicing variants of heat shock transcription factor 2 (). Furthermore, the overexpression of alternative splicing variants and in the homokaryotic S0301 strain showed opposite effects on the extracellular total laccase activity, with the maximum laccase activity of approximately 0.6 U mL and 3.0 U mL, respectively, on the eighth day, which is 0.4 and 2.3 times that of the wild type strain. Similarly, TtHSF2α and TtHSF2β-I play opposite roles in the oxidation tolerance to HO In addition, the direct binding of TtHSF2α to the promoter regions of the representative laccase isoenzymes ( and ) and protein-protein interactions between TtHSF2α and TtHSF2β-I were detected. Our results demonstrate the crucial roles of and its alternative splicing variants in response to Cu We believe that these findings will deepen our understanding of alternative splicing of HSFs and their regulatory mechanism of the laccase gene family in white-rot fungi. The members of laccase gene family in strains are the primary source of industrial laccase and have gained widespread attention. Increasing the yield and enzymatic properties of laccase through various methods has always been a topic worthy of attention, and there is no report on the regulation of laccase expression through HSF transcription factor engineering. Here, we found that two alternative splicing variants of functioned oppositely in regulating the expression of laccase genes, and copper can induce the expression of almost all members of the laccase gene family. Most importantly, our study suggested that and its alternative splicing variants are vital for copper-induced production of laccases in S0301.
白腐真菌，尤其是某些菌株，是生物能源和生物修复领域工业漆酶的主要来源。这些菌株表达具有不同物理化学性质和表达模式的漆酶基因家族成员。然而，关于白腐真菌菌株中漆酶基因家族在S0301中的表达模式以及对关键漆酶诱导剂铜的响应机制的文献却很匮乏。在本研究中，我们发现铜可以诱导热休克转录因子2（）的两种可变剪接变体的mRNA和蛋白质表达。此外，在同核S0301菌株中过表达可变剪接变体和对细胞外总漆酶活性表现出相反的影响，在第八天漆酶活性最大值分别约为0.6 U/mL和3.0 U/mL，分别是野生型菌株的0.4倍和2.3倍。同样，TtHSF2α和TtHSF2β-I在对H2O2的氧化耐受性中发挥相反作用。此外，检测到TtHSF2α与代表性漆酶同工酶（和）的启动子区域直接结合以及TtHSF2α和TtHSF2β-I之间的蛋白质-蛋白质相互作用。我们的结果证明了及其可变剪接变体在响应铜方面的关键作用。我们相信这些发现将加深我们对热休克因子可变剪接及其在白腐真菌中漆酶基因家族调控机制的理解。某些菌株中的漆酶基因家族成员是工业漆酶的主要来源并受到广泛关注。通过各种方法提高漆酶的产量和酶学性质一直是一个值得关注的话题，并且尚无通过热休克因子转录因子工程调控漆酶表达的报道。在此，我们发现的两种可变剪接变体在调节漆酶基因表达方面发挥相反作用，并且铜可以诱导几乎所有漆酶基因家族成员的表达。最重要的是，我们的研究表明和其可变剪接变体对于S0301中铜诱导的漆酶产生至关重要。
