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The detailed gene expression patterns of the selected functional groups in microarray analysis: (A) protease genes (43 in total); (B) cell wall and matrix protein genes (45); (C) genes involved in signaling pathways (47); (D) genes involved in synthesis of toxic metabolites (19). The blocks in gray mean the intensity values (Cy3 and Cy5) have been rescaled as zero after background filtering and normalization. Hierarchical cluster analysis was performed with 500 bootstrap replicates. ( * ) Genes with transcriptional expression varied significantly between the treatments.  

The detailed gene expression patterns of the selected functional groups in microarray analysis: (A) protease genes (43 in total); (B) cell wall and matrix protein genes (45); (C) genes involved in signaling pathways (47); (D) genes involved in synthesis of toxic metabolites (19). The blocks in gray mean the intensity values (Cy3 and Cy5) have been rescaled as zero after background filtering and normalization. Hierarchical cluster analysis was performed with 500 bootstrap replicates. ( * ) Genes with transcriptional expression varied significantly between the treatments.  

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Like many other fungal pathogens Metarhizium anisopliae is a facultative saprophyte with both soil-dwelling and insect pathogenic life-stages. In addition, as M. anisopliae traverses the cuticle and enters the hemolymph it must adapt to several different host environments. In this study, we used expressed sequence tags and cDNA microarray analyses...

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... genes in the exudate as compared to SDB (Figs. 2 and 3). The similarities between expres- sion patterns in hemolymph and cuticle were confirmed by bootstrap clustering analysis which revealed that expression patterns in the root exudate medium diverged first while expression patterns in the cuticle and hemo- lymph media clustered together (e.g., Fig. 3). This sug- gests there are critical differences in transcriptional control between pathogenic and saprophytic growth. Consistent with EST analysis of gene abundance, the cell metabolism (22.5%), cell structure and function (14.3%), and protein metabolism (10.4%) categories contained most of the genes with variable expressions. A large ...
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... expression profiles of protease genes demon- strated that 18 out of 43 protease unigenes are differen- tially expressed (Fig. 3A). Consistent with EST analysis, and not surprisingly given its proteinaceous nature, most of these genes were upregulated during growth on cuticle, but except for pr1A they were downregulated in root exudate. Microarray analysis also confirmed that except for the endocellular subtilisin pr1H (up 2.8-fold), the serine proteases and the ...
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... analysis also confirmed that except for the endocellular subtilisin pr1H (up 2.8-fold), the serine proteases and the metalloproteases that are highly represented in the cuticle library (Table 2) were downregulated in hemolymph. Only two aspartic prote- ases (CN809214 and CN809604) and a few proteasome subunits were upregulated in hemolymph (Fig. 3A). Genes encoding ribosomal proteins and translational machinery such as elongation factors were coordinately up regulated in hemolymph compared to SDB, while the same genes were usually downregulated in root exudates (supplementary Table ...
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... analysis further verified the EST analysis by showing up regulation of 21 out of 45 arrayed genes involved in the cell wall structure and associated matrix in the cuticle and hemolymph media as compared to SDB and root exudates (Fig. 3B). Given that the cell wall/matrix provides the interface with the environment, this suggests that pathogenic adaptations involve unique interactions with host materials. These interactions apparently change as pathogenesis proceeds assuming that differences in the genes upregulated in cuticle and hemolymph media indicate alterations in ...
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... interactions with host materials. These interactions apparently change as pathogenesis proceeds assuming that differences in the genes upregulated in cuticle and hemolymph media indicate alterations in cell surface properties. For example, the sequence CN808879 with similarity (E = 8 · 10 À19 ) to an Aspergillus kawachii cell wall protein (1 in Fig. 3B) was highly upregulated in the H-medium (25.7-fold) but minimally downregulated in the C-medium. A chitinase isoform 2 (CN808472) was more highly expressed in the C-medium (5.5-fold) than in the H-medium (2.9-fold) while conversely a chitinase 3 (AJ274327) was more dramatically induced in the H- medium (14.2-fold) than in the C-medium ...
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... was highly upregulated in the H-medium (25.7-fold) but minimally downregulated in the C-medium. A chitinase isoform 2 (CN808472) was more highly expressed in the C-medium (5.5-fold) than in the H-medium (2.9-fold) while conversely a chitinase 3 (AJ274327) was more dramatically induced in the H- medium (14.2-fold) than in the C-medium (3.0-fold) (Fig. ...
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... to the C-and R-libraries, the H-library contained more ESTs for genes involved in signal transduction (Table 1). While microarray analysis indi- cated that most of these genes (47 in total) were also up regulated when the fungus was grown on cuticle as compared to SDB, none of these genes were upregulated in the R-medium (Fig. 3C), suggesting that they play a particular role in adaptation to host-related media. Interestingly, the EST CN808063 that is most similar (E = 3 · 10 À20 ) to the Magnaporthe grisea appressorial protein MAS1 was more highly up regulated in response to hemolymph (13.7-fold) than cuticle (2.6-fold). Two ESTs with homologs in Gibberella ...
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... ESTs with homologs in Gibberella zeae encoding a cross-pathway control protein (CN809551, E = 1.0 · 10 À143 ) and a 14-3-3 protein with multiple functions (CN809566, E = 1.0 · 10 À128 ) were also more dramatically upregulated in the H-medium (30.9-fold and 17.3-fold, respectively) than in the cuticle medium (5.7-fold and 2.9-fold, respectively) (Fig. ...
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... analysis of the H-library identified 19 transcripts with homologs involved in synthesis of secondary toxic metabolites. Microarray analysis confirmed high level expression of most of these genes in both hemolymph and cuticle. None of these genes was upregulated in root exudate as compared to SDB (Fig. ...
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... to resource limitation, our sampling of the libraries was not exhaustive. Pre- sumably for this reason only 22 overlapping genes were identified between libraries from sequencing analysis (Fig. 1) while microarray analysis confirmed most of the singletons identified from one library, were also ex- pressed under the other growth conditions (e.g., Fig. 3), albeit usually at lower levels. For example, CN808183 (glyoxal oxidase) and CN808491 (xylulose- 5-phosphate/fructose-6-phosphate phosphoketolase), specifically identified in the H-library were both more than 2-fold up regulated during growth on cuticle as compared to expression in SDB. Likewise, the two C-4 methyl sterol oxidases from ...
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... microarray data verified upregulation of two aspartic proteases in hemolymph (Fig. 3A), suggest- ing that M. anisopliae can still scavenge host proteins and/or these proteases have a role in inactivating anti- fungal host proteins (e.g., Frobius et al., 2000). Aspartic proteases are virulence determinants for other fungi (e.g., Hube, 1996) and in contrast to serine proteases, are not involved in activation of insect ...
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... the subtilisin pr1A, trypsins are not upregu- lated in root exudate (Table 2; Fig. 3A), even though these are the most abundant transcripts in the C-library ( Freimoser et al., 2003a). Pr1A expression also occurs during nutrient deprivation suggesting it may be more sensitive to the availability of nutrients rather than their identity ( Freimoser et al., 2003a;St. Leger et al., 1991, 1994 and this may explain the ...
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... wall reorganization during growth in the host-re- lated media involved upregulation of 19 genes (Fig. 3B) suggesting that adaptation to host niches requires major modifications to the pathogens interface with the envi- ronment. Except for chitinases ), none of these genes has been investigated as potential virulence factors for insect pathogenic fungi. Among the most abundant transcripts tagged in the H-library were various cell wall ...
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... in hemolymph. Thus, homologs of transmembrane osmosensors from S. cerevisiae (CN808248, E = 6 · 10 À29 ) and Kluyver- omyces lactis (CN809474, E = 6 · 10 À29 ) were upregu- lated at higher levels in the H-medium (3.8-fold and 4.8-fold, respectively) than the C-medium (2.0-fold and 2.7-fold, respectively) and were not upregulated in root exudates (Fig. 3C). An enzyme (CN809060) similar (E = 6 · 10 À42 ) to an Aspergillus niger mannitol-1-phos- phate dehydrogenase (the first component of the mannitol synthesis pathway) was sharply upregulated (22.4-fold) in hemolymph. D-Mannitol is a major polyol (osmatolyte) in conidia of M. anisopliae isolated directly from insects and the protection ...
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... of signal transduction pathways have long been recognized as being involved in fungal devel- opment and virulence (e.g., Borges-Walmsley and Walmsley, 2000). Both EST and microarray analyses showed differential expression of transduction chains during growth in SDB, root exudates, and host media (Table 1; Fig. 3C). Pathways associated with infection structure differentiation and virulence in other fungal species include the cAMP and mitogen-activated protein (MAP) kinase signaling systems which are themselves regulated by upstream G and ras components (BorgesWalmsley and Walmsley, 2000;Leberer et al., 2001;Nishimura et al., 2003;Xu, 2000). The ...
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... to ras proteins from Yarrowia lipolytica (CN808484) and N. crassa (CN808398) (E = 4.0 · 10 À21 and E = 4.0 · 10 À93 , respectively) were sharply upregulated in both cuticle and hemolymph. However, the cAMP-pathway genes acy (AJ251971) and pka (AJ273794) and the MAP asso- ciated transcripts (AJ272796 and AJ273356) were not differentially expressed (Fig. 3C). Likewise, although expression of pr1A differed significantly between media with diverse carbon and nitrogen compositions, the car- bon regulator protein Crr1 ( Screen et al., 1997) and the nitrogen regulator Nrr1 (Screen et al., 1998) were not differentially expressed. It is possible that other path- ways regulate protease production. ...
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... virulence factors (Flieger et al., 2001) were upregulated in both the cuticle and hemolymph media. However, most genes involved in the synthesis of toxic metabolites were expressed more highly in hemolymph than the cuticle, which could be adaptive as there would be greater accessibility of the targets for these toxins in the insectsÕ body cavity (Fig. ...

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... Similar interkingdom interactions have likely driven the evolution of other plant-associated soil fungi, which have acquired the ability to infect and kill insects, giving rise to new lineages of endophytic insect pathogens characterized by multifunctional lifestyles (73). In this context, the entomopathogenic Metarhizium is an excellent example of a fungus with genotypic plasticity allowing a multifunctional lifestyle, ranging from insect pathogen to plant colonizer or saprotroph depending upon exposure to different environmental conditions (74)(75)(76). ...
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... For example, Metarhizium is a soil-inhabiting insect-pathogenic fungus worldwide and is currently used as a biocontrol agent against crop pests (Sasan & Bidochka, 2012). Other fungi known as insect pathogens include Acremonium, Beauveria, Cladosporium, Clonostachys, and Isaria (Wang et al., 2005). ...
... The rhizosphere is a highly competitive environment in which microbes exhibit different strategies for survival. Entomopathogenic fungi (EPF) are commonly found in the rhizosphere, using root exudates as a source of nutrition but switching to insects when the opportunity arises [1][2][3][4][5]. EPF form symbiotic relationships with plants, leading to improved plant growth and productivity [1,6]. ...
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... Entomopathogenic fungi were intended to develop in almost all groups of insects as inundative biocontrol agents of insects, mites, and ticks Goettel et al. 2005). These fungi's difference in pathogenicity from bacteria and viruses is that they infect insects by breaching the host cuticle and by secreting extracellular enzymes like chitinases, lipases, and proteases to degrade the major constituents of the cuticle (i.e., lipids, chitin, and protein) and permit hyphal penetration (Wang et al. 2005;Cho et al. 2006). Many toxic substances such as small secondary metabolites, cyclic peptides, and macromolecular proteins are recorded from entomopathogenic fungi. ...
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... There is however little information about this phenomenon and how EPF stability changes when cultured on artificial media, but Brownbridge et al. (2001) believed the attenuation of virulence may be due to random mutation or caused by subculture conditions. Wang et al. (2005b) and Wang and St Leger (2005) studies on M. anisopliae returned this to the pathogenicity-related genes, which are upregulated differently when the fungus grows on different artificial media or media containing insect hemolymph. ...
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... The large secretomes of insect pathogens probably reflect the many microhabitats they must adapt to in insecta, including the cuticle and the haemolymph, as well as additional environmental habitats in the soil and with plants. These complex lifestyles are reflected in transcriptional reprogramming involving hundreds of differentially expressed genes as Metarhizium strains rapidly adapt to host cuticles, haemolymph or root exudate [61,62]. The ability to recognize appropriate hosts, and penetrate their cuticle, are among the necessary steps for the transition from either saprophyte or root colonizer to pathogen. ...
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... Rather, this genus exhibits extraordinary transcriptional plasticity, modulating the transcriptome to allow for physiological adaptation to environments with diverse and dynamic exploitable nutrient sources, including decaying organic matter, plants, and soil insects. Expressed sequence tag and cDNA microarray experiments have demonstrated this phenomenon of adaptive transcriptional control, with Metarhizium exhibiting largescale changes in gene expression patterns when grown in insect cuticle, hemolymph, and plant root exudate (a model for growth in the rhizosphere) (Wang et al. 2005). ...
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... The integument is made up of polysaccharide glucosamine polyose fibrils inset with pigments, proteins, lipids, and N-acyl catecholamines (Richard et al. 2010). Extracellular fluid containing enzymes, lipases, proteases, and chitinases is released and degrades the main components of the cuticle (i.e., lipids, proteins, and chitin), allowing penetration of the fungus (Wang et al. 2005;Cho et al. 2006a). Lipase enzymes have complicated pathogen acrimony and play various roles in the process of microbial infection (Stehr et al. 2003). ...
... However, the main problem limiting the marketability of mycobiopesticides is that they take more time to kill their target hosts than chemical pesticides do ( view enhance as well as ameliorate acerbity of such mold to a bigger expanse than its personal action that accelerates application of formulated products present in market. Excellent quantity of transcribe and gene modification work of entomopathogenic molds contamination procedure let out availability few different genes participate in the pathogenic action in the same way as chitinase enzymes (Cho et al. 2006b(Cho et al. , 2007Wang et al. 2005;Fang et al. 2005;Bagga et al. 2004). Guanine nucleotide-binding protein and its regulator (Fang et al. , 2008, adhesin, aid the attachment of spores. ...