Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
FEBS Lett. 2020 Oct;594(19):3182-3199. doi: 10.1002/1873-3468.13890. Epub 2020 Aug 4.
White-rot fungi efficiently degrade lignin and, thus, play a pivotal role in the global carbon cycle. However, the mechanisms of lignin degradation are largely unknown. Recently, mutations in four genes, namely wtr1, chd1, pex1, and gat1, were shown to abrogate the wood lignin-degrading ability of Pleurotus ostreatus. In this study, we conducted a comparative transcriptome analysis to identify genes that are differentially expressed in ligninolysis-deficient mutant strains. Putative ligninolytic genes that are highly expressed in parental strains are significantly downregulated in the mutant strains. On the contrary, many putative cellulolytic and xylanolytic genes are upregulated in the chd1-1, Δpex1, and Δgat1 strains. Identifying transcriptional alterations in mutant strains could provide new insights into the regulatory mechanisms of lignocellulolytic genes in P. ostreatus.
白腐真菌能够高效降解木质素，因此在全球碳循环中起着关键作用。然而，木质素降解的机制在很大程度上仍是未知的。最近的研究表明，wtr1、chd1、pex1 和 gat1 这四个基因的突变会使糙皮侧耳丧失木质素降解能力。在本研究中，我们进行了比较转录组分析，以鉴定木质素分解缺陷突变株中差异表达的基因。在亲本菌株中高表达的推定木质素降解基因在突变株中显著下调。相反，在 chd1-1、Δpex1 和 Δgat1 菌株中，许多推定的纤维素酶和木聚糖酶基因上调。鉴定突变株中的转录变化可以为糙皮侧耳木质素降解基因的调控机制提供新的见解。
