BcCFEM1, a CFEM Domain-Containing Protein with Putative GPI-Anchored Site, Is Involved in Pathogenicity, Conidial Production, and Stress Tolerance in Botrytis cinerea

Abstract

We experimentally isolated and characterized a CFEM protein with putative GPI-anchored site BcCFEM1 in Botrytis cinerea. BcCFEM1 contains a CFEM (common in several fungal extracellular membrane proteins) domain with the characteristic eight cysteine residues at N terminus, and a predicted GPI modification site at C terminus. BcCFEM1 was significantly up-regulated during early stage of infection on bean leaves and induced chlorosis in Nicotiana benthamiana leaves using Agrobacterium infiltration method. Targeted deletion of BcCFEM1 in B. cinerea affected virulence, conidial production and stress tolerance, but not growth rate, conidial germination, colony morphology, and sclerotial formation. However, over expression of BcCFEM1 did not make any observable phenotype change. Therefore, our data suggested that BcCFEM1 contributes to virulence, conidial production, and stress tolerance. These findings further enhance our understanding on the sophisticated pathogenicity of B. cinerea beyond necrotrophic stage, highlighting the importance of CFEM protein to B. cinerea and other broad-host-range necrotrophic pathogens.

Genome-Wide Identification of Effector Candidates With Conserved Motifs From the Wheat Leaf Rust Fungus Puccinia triticina

“…Fungal-specific CFEM effectors normally contain at least eight conserved cysteine residues ( Figure 5B) and are considered extracellular avirulent effectors that triggering plant immunity responses (Catanzariti et al, 2006;. For example, a CFEM domain-containing protein BcCFEM1 from Botrytis cinerea directly induced chlorosis in N. benthamiana (Zhu et al, 2017). A CFEM effector found here, PTTG_08198, accelerated plant cell death triggered by BAX protein and induced higher accumulation of ROS in tobacco leaves (Figure 7B).…”

Transcriptome analysis of the plant pathogen Sclerotinia sclerotiorum interaction with resistant and susceptible canola (Brassica napus) lines

“…Kou et al [117] showed that deletion of pth11 results in disruption of redox homeostasis and thus affects appressorium formation during pathogenesis. In B. cinerea, a closely related broad-host-range necrotroph, BcCFEM1, a CFEM containing gene, plays a key role in stress resistance and virulence [118]. BcCFEM1 also has a potential elicitor role.…”

First molecular insights into the infection process provoked by Neofusicoccum parvum in Liquidambar styraciflua and the identification of new cysteine-rich proteins in both organisms

“…In accordance with the report by Zhang and collaborators, a positive correlation between CFEM domain occurrence and fungal pathogenicity was shown [37], and it seems that the occurrence of CFEM domain proteins is independent of the lifestyle of the pathogen (i.e., biotrophic, hemibiotrophic or necrotrophic). For example, in Botrytis cinerea (a necrotrophic fungus), BcCFEM1 is highly expressed at early stages of infection in Phaseolus vulgaris, and gene disruption results in decreased virulence [53]. For Magnaporthe grisea, a hemibiotrophic lamentous ascomycete, the mutant pth11 (mutated in a CFEM transmembrane protein) is impaired in appressorium maturation, which has an effect on infection capacity [54].…”