Project description:The ascomycete fungus Beauveria bassiana is a pathogen of hundreds of insect species and is commercially produced as an environmentally friendly mycoinsecticide. Genome-wide insight into the infection of the fungi is critical for genetic improvement of fungal insecticides but has been poorly explored. We constructed three transcriptomes of Beauveria bassiana at 24, 48 and 72 hours post treatment of infection (BbI) and of control (Bbc). Overall design: 1,Beauveria bassiana groewn on PDA medium. 2,Beauveria bassiana at 24 hours post treatment of infection. 3, Beauveria bassiana at 48 hours post treatment of infection. 4, Beauveria bassiana at 72 hours post treatment of infection
Project description:Transcriptomic analysis of LaeA-deletion and overexpression LaeB in LaeA deletion strains in fungus Beauveria bassiana Examination of differential gene expressions by Beauveria bassiana wild type, LaeA-deletion and overexpression LaeB in LaeA deletion strains in fungus Beauveria bassiana
Project description:Insect pathogenic fungus Beauveria bassiana in one of the best studied insect biocontrol fungus, which infects insects by cuticle penetration. After breaking the cuticles, the fungus will propagate in insect hemocoel and kill insect hosts. It has also been found that the mycelia of B. bassiana can penetrate plant tissues to reach insect inside plant, e.g. corn borer (Ostrinia furnacalis), but do not cause damage to plants. The mechanism of fungal physiological plasticity is poorly understood. To accompany our genome sequencing work of B. bassiana strain ARSEF 2860, fungal transcriptional responses to different niches were studied using an Illumina RNA_seq technique. To examine fungal response to insect cuticle, conidia were inoculated on locust hind wings for 24 hours before used for RNA extraction. To evaluate fungal adaptation to insect hemocole, the fifth instar larvae of cotton bollworms were injected with spore suspension and fungal cells isolated by centrifugation in a step gradient buffer. To unveil the mechanism of interaction with plants, the fungus was grown in corn root exudates for 24 hours. After RNA sequencing, around three million tags were acquired for each sample and fungal transcriptional profiles were compared. Unveiling gene differential expression patterns when the insect biocontrol fungus Beauveria bassiana grown in insect hemocoel, corn root exudates and on insect cuticles.
Project description:Virulence is a key trait under selection during host-parasite coevolution. In order to obtain increased fitness, parasites are predicted to increase their ability to circumvent and overcome host immunity. A particular challenge for pathogens are external immune systems, found among various invertebrates. Such external immune systems are chemical defence systems comprised of highly potent antimicrobial compounds released by prospective hosts into the environment. We carried out a coevolution experiment with the entomopathogenic fungus, Beauveria bassiana, and the red flour beetle, Tribolium castaneum, which has a well-documented external immune system. Surprisingly, after just seven transfers of experimental evolution we saw a significant increase in virulence in all B. bassiana. This increase in virulence was mainly the result of the B. bassiana isolates evolving resistance to the external immune defences of the T. castaneum beetles, but not obviously through the increased production of toxins or other harmful substances. Furthermore, transcriptomic analyses of B. bassiana RNA-seq data implicates up-regulation of genes responsible for resistance to oxidative stress underlying the observed resistance. We conclude that external immunity acts as a powerful selective force for virulence evolution, with an increase in virulence being achieved apparently entirely by overcoming these defences, most likely due to elevated oxidative stress resistance. Overall design: mRNA profiles of Beauveria bassiana (ancestral: A and evolved isolates:BI5 & BI3) exposed to either 10µl of Methyl-para-benzoquinone (MBQ, quinone, 0.11µg per ml diluted in methanol) or methanol at 72h or 96h were generated by deep sequencing, in triplicate or single, using Illumina HiSeq2000.
Project description:Ssk1-type response regulator proteins are the core elements of histidine-to-aspartate systems that mediate fungal stress tolerance, a determinant to the biocontrol potential of fungal entomopathogens. We characterized for the first time the functions of Beauveria bassiana Ssk1 (Bbssk1) by analyzing multi-phenotypic changes in DBbssk1 and differentially expressed genes (DEGs) in the digital gene expression (DGE) libraries of DBbssk1 and wild-type constructed under osmotic stress. The results revealed 1003 DEGs, of which many associated with conidiation, xenotics transport, cell wall integrity, and protein and carbohydrate metabolism were greatly down-regulated. Total RNA obtained from Bbssk1 disruption mutant subjected to 0.5 M NaCl for 30 minutes compared to the wild type strain under the same stress treatment.
Project description:We investigated the transcriptional response of invasive Mediterranean (MED) species of the whitefly B. tabaci complex (commonly referred to as Q biotype) to entomopathogenic fungi Beauveria bassiana using Illumina sequencing technology. Overall design: Nearly 1,000 of control whiteflies, 48h fungal-induced whiteflies and 72h fungal-induced whiteflies were collected, respectively.
Project description:We investigated the transcriptional response of invasive Mediterranean (MED) species of the whitefly B. tabaci complex (commonly referred to as Q biotype) to entomopathogenic fungi Beauveria bassiana using Illumina sequencing technology. Nearly 1,000 of control whiteflies, 48h fungal-induced whiteflies and 72h fungal-induced whiteflies were collected, respectively.