CgGCS, Encoding a Glucosylceramide Synthase, Is Required for Growth, Conidiation and Pathogenicity in Colletotrichum gloeosporioides

Abstract

Fungal glucosylceramide plays important role in cell division, hyphal formation and growth, spore germination and the modulation of virulence and has recently been considered as target for small molecule inhibitors. In this study, we characterized CgGCS, a protein encoding a glucosylceramide synthase (GCS) in Colletotrichum gloeosporioides . Disruption of CgGCS resulted in a severe reduction of mycelial growth and defects in conidiogenesis. Sphingolipid profile analysis revealed large decreases in glucosylceramide production in the mutant strains. Pathogenicity assays indicated that the ability of the Δ CgGCS mutants to invade both tomato and mango hosts was almost lost. In addition, the expression levels of many genes, especially those related to metabolism, were shown to be affected by the mutation of CgGCS via transcriptome analysis. Overall, our results demonstrate that C. gloeosporioides glucosylceramide is an important regulatory factor in fungal growth, conidiation, and pathogenesis in hosts.

Loss of glucosylceramide synthase impairs the growth and virulence of Fusarium oxysporum f. sp. cubense

“…We speculate that growth deficiency in Foc TR4 may contribute to its impaired pathogenesis. Furthermore, knockout of FocGCS reduced the virulence of Foc TR4 on host plants, consistent with the previous studies (Zhu et al 2014;Huang et al 2019). The characterization of FocGCS knockout mutant in this study provides insight into the functional roles of this enzyme in vivo.…”

“…Unlike in S. cerevisiae, GlcCers are produced in filamentous and dimorphic fungi, such as C. albicans, F. graminearum, and P. digitatum (Dickson and Lester 2002;Ramamoorthy et al 2007;Noble et al 2010;Zhu et al 2014). Disruption of GCS can reduce mycelial growth and virulence of pathogenic fungi (Rittershaus et al 2006;Ramamoorthy et al 2007;Zhu et al 2014;Huang et al 2019). In our study, deletion of FocGCS severely retarded the growth of Foc TR4 (38% reduction in growth rate compared with the WT and complemented strains) (Fig.…”

“…Glucosylceramide synthase (GCS) catalyzes the transfer of a sugar residue from UDP-glucose to ceramide to form GlcCer (Wang et al 2021). Although the GCS gene is absent in Saccharomyces cerevisiae, it is present in most of the other fungal species studied so far, such as phytopathogens Magnaporthe grisea, Colletotrichum gloeosporioides, and Fusarium graminearum (Leipelt et al 2001;Dickson and Lester 2002;Ramamoorthy et al 2007;Del Poeta et al 2014;Huang et al 2019). Several studies have suggested that GlcCer modulates membrane physical properties and physiological functions in some fungal pathogens of humans to facilitate fungal growth, spore germination, virulence, and hyphal development and differentiation (Levery et al 2002;Warnecke and Heinz 2003;Thevissen et al 2004;Ramamoorthy et al 2007;Zhu et al 2014).…”

“…In the phytopathogen Penicillium digitatum, deletion of PdGcs1 resulted in impaired virulence on citrus fruits (Zhu et al 2014). In C. gloeosporioides, CgGCS-knockout mutants almost completely lost the ability to invade natural host plants tomato (Solanum lycopersicum) and mango (Mangifera indica) (Huang et al 2019). However, the role of GCS in pathogenesis of F. graminearum is host-dependent (Ramamoorthy et al 2007).…”

Securing fruit production: Opportunities from the elucidation of the molecular mechanisms of postharvest fungal infections

“…The suppression of gcs1 gene encoding GCS in P. digitatum preferentially oriented the metabolism to spore formation, which restricted the germination and delayed the virulence to citrus fruits (Zhu et al., 2014). Its homologue gene is also required for growth, sporulation, and virulence in C. gloeosporioides (Huang et al., 2019).…”