The interaction between the histone acetyltransferase complex Hat1‐Hat2 and transcription factor AmyR provides a molecular brake to regulate amylase gene expression

Abstract

The chromatin structure is generally regulated by chromatin remodelers and histone modifiers, which affect DNA replication, repair, and levels of transcription. The first identified histone acetyltransferase was Hat1/KAT1, which belongs to lysine (K) acetyltransferases. The catalytic subunit Hat1 and the regulatory subunit Hat2 make up the core HAT1 complex. In this study, the results of tandem affinity purification and mass spectrometry and bimolecular fluorescence complementation proved that the Penicillium oxalicum PoHat1‐Hat2 is the transcriptional cofactor of the sequence‐specific transcription factor PoAmyR, a transcription activator essential for the transcription of amylase gene. ChIP‐qPCR results demonstrated that the complex PoHat1‐Hat2 is recruited by PoAmyR to the promoters of prominent amylase genes Poamy13A and Poamy15A and performs histone H4 lysine12 acetylation. The result of the yeast two‐hybrid test indicated that PoHat2 is the subunit that directly interacts with PoAmyR. PoHat1‐Hat2 acts as the molecular brake of the PoAmyR‐regulating transcription of amylase genes. A putative model for amylase gene regulation by PoAmyR‐Hat2‐Hat1 was constructed. Our paper is the first report that the Hat1‐Hat2 complex acts as a cofactor for sequence‐specific TF to regulate gene expression and explains the mechanism of TF AmyR regulating amylase genes expression.

Different Putative Methyltransferases Have Different Effects on the Expression Patterns of Cellulolytic Genes

“…Furthermore, we reviewed the transcriptome data retrieved from the Gene Expression Omnibus (GEO) database of NCBI (https://www.ncbi.nlm.nih.gov/geo/, accessed on 10 October 2022). These data came from the different cultivation conditions when P. oxalicum WT was cultivated on different carbon sources, including glucose (GSE106558) [31], starch (GSE175682) [32], cellulose [28], and cellulose plus wheat bran (GSE 106558) [31]. Pomtr23B, Pomtr25A, and Pomtr23C have the top three highest transcriptional levels among the ten methyltransferase genes under the glucose condition (Figure 2B).…”

A RsrC-RsrA-RsrB transcriptional circuit positively regulates polysaccharide-degrading enzyme biosynthesis and development in Penicillium oxalicum

“…For instance, the key activator AmyR, a homolog of COL26 in Neurospora crassa, binds the promoters of genes encoding prominent amylases including RSDG PoxGA15A and α-amylase Amy13A. In addition, AmyR interacts with histone acetyltransferase complex Hat1-Hat2, acting as a molecular brake to regulate expression of amylase genes 9 . The repressor CxrC, containing an Zn(II)2Cys6 zinc nger domain, negatively regulates the expression of genes encoding major RSDEs 10 .…”