Chromatin accessibility of Meyerozyma guilliermondii under patulin stress

Abstract

Patulin (PAT) is a significant mycotoxin contaminant in apples and their product. Antagonist yeasts can inhibit PAT production or degrade PAT in vivo or in vitro. Our previous study reported that Meyerozyma guilliermondii, an antagonistic yeast, could degrade PAT. The present study aims to explore the molecular mechanisms of M. guilliermondii in response to PAT stress by chromatin accessibility sequencing. After PAT treatment, four genes were up-regulated, and 146 were down-regulated in M. guilliermondii. Gene Ontology (GO) analysis showed that differential expression of genes related to yeast growth, stimulus-response, and activity. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment results showed that PAT stress caused toxic damage to the yeast by affecting the functions such as steroid biosynthesis, ATP-binding cassette (ABC) transporters, autophagy-yeast, messenger RNA (mRNA) surveillance pathways, mitogen activated protein kinase (MAPK) signaling pathway and protein processing in the endoplasmic reticulum. Gene function analysis showed that multidrug resistance protein encoding gene (MDR1), heat shock protein 70 kDa encoding gene (SSC1) and 14-3-3 protein encoding gene (BMH1) might participate in the detoxification of PAT by M. guilliermondii through the stress response. In addition, these three genes might be regulated by the yeast activator protein (YAP) sub-family. In short, the information obtained in this study reveals the regulatory role of related transcription factors in M. guilliermondii responding to PAT stress.