2026-10-06T14:26:30Z https://www.scidb.cn/oai

10.57760/sciencedb.012wr 2026-09-28T17:00:31Z

2026-09-28 Programmable Histone Acetylation Enables Reversible Regulation of Cellulase Production in Myceliophthora thermophila doi:10.57760/sciencedb.012wr en Myceliophthora thermophila is a thermophilic filamentous fungus with great potential for biomass biorefining and industrial protein production. Lignocellulolytic enzyme production in this fungus is governed by regulatory networks that integrate environmental sensing, transcriptional regulation, and protein secretion. However, the locus-specific epigenetic control of these networks remains poorly understood, particularly in thermophilic fungi. Here, we established a CRISPR/dCas9-p300 histone acetylation system in M. thermophila and targeted the promoters of the key cellulolytic regulators Clr-1, Clr-2, and Xyr-1. Targeted recruitment of dCas9-p300 increased the transcription of these regulators by up to 5.2-fold and promoter-associated histone acetylation by approximately 2- to 3-fold. Simultaneous targeting of all three regulators resulted in greater increases than single-locus targeting, with extracellular protein production and CMCase activity increasing by up to 5.5- and 3.7-fold, respectively. The dependence of these effects on guide RNA-directed targeting and p300 catalytic activity was confirmed using no-guide controls and the selective p300 inhibitor A-485. We further developed an inducible dCas9-p300 system to examine the persistence and reversibility of the activated state. Following inducer withdrawal, the high cellulase-production phenotype was maintained during the initial propagation but gradually declined over successive passages and was restored upon re-induction. These results demonstrate that targeted histone acetylation can coordinately activate an endogenous cellulolytic regulatory network and establish a reversible high-production state without altering the DNA sequences of the target loci. This work provides a chromatin-39 based strategy for reversible regulation of endogenous gene networks and protein production in filamentous fungi. Myceliophthora thermophila; Cellulase production; CRISPR/dCas9; Epigenetic engineering; Histone acetylation; Transcriptional regulation Yao Li Xiucai Zhao Xinyu Yang Jiaxin Wang Dandan Liu Qilin Yu Qian Liu Chaoguang Tian RESTRICTED dataset Science Data Bank