Comparative genome analysis of entomopathogenic fungi reveals a complex set of secreted proteins

Abstract

BackgroundMetarhizium anisopliae is an entomopathogenic fungus used in the biological control of some agricultural insect pests, and efforts are underway to use this fungus in the control of insect-borne human diseases. A large repertoire of proteins must be secreted by M. anisopliae to cope with the various available nutrients as this fungus switches through different lifestyles, i.e., from a saprophytic, to an infectious, to a plant endophytic stage. To further evaluate the predicted secretome of M. anisopliae, we employed genomic and transcriptomic analyses, coupled with phylogenomic analysis, focusing on the identification and characterization of secreted proteins.ResultsWe determined the M. anisopliae E6 genome sequence and compared this sequence to other entomopathogenic fungi genomes. A robust pipeline was generated to evaluate the predicted secretomes of M. anisopliae and 15 other filamentous fungi, leading to the identification of a core of secreted proteins. Transcriptomic analysis using the tick Rhipicephalus microplus cuticle as an infection model during two periods of infection (48 and 144 h) allowed the identification of several differentially expressed genes. This analysis concluded that a large proportion of the predicted secretome coding genes contained altered transcript levels in the conditions analyzed in this study. In addition, some specific secreted proteins from Metarhizium have an evolutionary history similar to orthologs found in Beauveria/Cordyceps. This similarity suggests that a set of secreted proteins has evolved to participate in entomopathogenicity.ConclusionsThe data presented represents an important step to the characterization of the role of secreted proteins in the virulence and pathogenicity of M. anisopliae.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2164-15-822) contains supplementary material, which is available to authorized users.

Secondary metabolite gene clusters in the entomopathogen fungus Metarhizium anisopliae: genome identification and patterns of expression in a cuticle infection model

“…As a control, the fungus was cultivated in 100 mL of liquid Cove’s complete medium (MCc) for 48 h (48hC) at 28 °C. The detailed RNA-seq experimental procedure, sequencing and data management have been previously described [32], and sequencing data are available under accession number PRJNA257269.…”

Managing the plant microbiome for biocontrol fungi: examples from Hypocreales

“…exhibit high genetic and virulence diversity [27, [36][37][38][39][40]. Comparative genomic analyses for both genera have revealed qualitative differences in gene content that are potentially important in determining host virulence [41][42][43][44][45]. Additional genomic resources for related genera promise to expand the range of inferences possible for the underlying genetics of entomopathogen ecology [46,47].…”

Coevolution of parasitic fungi and insect hosts

“…anisopliae was the first entomopathogenic fungus for which a whole sequenced genome became available (Gao et al, 2011;Staats et al, 2014). The genomic sequence of B. bassiana revealed similar adaptations to the parasitic life style as that of M. anisopliae (Xiao et al, 2012).…”