Analysis of the chitin synthase gene family in Ganoderma lucidum: its structure, phylogeny, and expression patterns

Chitin synthases are essential enzymes in fungi, contributing to various biological processes such as hyphal growth, sporulation, and cell wall stability. Despite their well-documented functions in other fungal species, the specific roles of chitin synthases in Ganoderma lucidum remain unexplored. This investigation systematically characterized the complete chitin synthase gene family in Ganoderma lucidum.

A comprehensive analysis was conducted using bioinformatics tools to examine genomic localization, gene structure, conserved domains, and phylogenetic evolution. By employing bioinformatic approaches, the study investigated promoter cis-elements and expression patterns to elucidate the regulatory mechanisms of these genes in G. lucidum.

In G. lucidum, eight chitin synthase (GlCS) family members were identified and phylogenetically classified into five distinct classes. Our investigation revealed stage-specific expression patterns of GlCS genes throughout the fungal development process. GlCS1, GlCS2, GlCS5, GlCS6, and GlCS8 exhibited significantly greater expression levels in the early fruiting body (EA) stage than in the other developmental phases. In the mature fruiting body (MA) stage, GlCS3 was predominantly expressed. In the primordium formation (PR) stage, GlCS7 exhibited peak expression levels. Six genes (GlCS1, GlCS3, GlCS4, GlCS6, GlCS7, and GlCS8) were markedly upregulated under 40 °C thermal stress, suggesting their potential roles in thermotolerance mechanisms. These findings demonstrate functional diversification among GlCS family members across different developmental stages and stress conditions.