The entomopathogenic fungus Beauveria bassiana activate toll and JAK-STAT pathway-controlled effector genes and anti-dengue activity in Aedes aegypti

Abstract

Here we investigated the effect of Beauveria bassiana infection on the survival of A. aegypti mosquitoes and the modulation of their susceptibility to dengue virus infection. Application of B. bassiana caused a reduction in the life span of A. aegypti and hindered dengue virus replication in the mosquito midgut. Fungus infection induced the expression a variety anti-microbial and dengue virus restriction factor genes. Transient reverse genetic analyses showed that the JAK-STAT pathway is implicated anti-fungal defense of Aedes mosquitoes. Our data suggest that this B. bassiana-mediated anti-dengue activity is likely to be at least partly indirectly mediated through the activation of the mosquito's anti-dengue Toll and JAK-STAT pathways.

Entomopathogenic fungi as potential biocontrol agents of the ecto-parasitic mite, Varroa destructor, and their effect on the immune response of honey bees (Apis mellifera L.)

“…The entomopathogenic fungal infection appears to have triggered the immune system of the bee brood. Another example of this outcome is B. bassiana infection of the mosquito, Aedes aegypti, which induced expression of the defense-related genes, attacin, cecropin G, defensin A and C, and diptericin (Dong et al, 2012). However, not all defense-related genes of the mosquito were up-regulated, such as lysozyme C, which is similar to this study where there was no effect of fungal infection on expression of SiMd in the honey bee brood.…”

Annotation of the Asian Citrus Psyllid Genome Reveals a Reduced Innate Immune System

“…The Janus kinase/signal transducer activator of transcription (JAK/STAT) pathway functions in embryonic development, and participates in humoral and cellular immune responses to bacteria, fungi, parasitoids, and viruses (Sorrentino et al, 2004; Dostert et al, 2005; Cronin et al, 2009; Souza-Neto et al, 2009; Dong et al, 2012b; Kingsolver et al, 2013). Unlike the Toll and Imd pathways, which are activated in response to PRR binding to PAMPs, the JAK/STAT pathway is activated by cytokines (Harrison et al, 1998; Agaisse and Perrimon, 2004).…”

The mosquito microbiota influences vector competence for human pathogens

“…Another NF-kB signaling pathway, the Imd pathway, plays an important role in the insects’ immune responses to bacteria, viruses, and the human Plasmodium parasite P. falciparum [29–32]. The insect JAK/STAT pathway is analogous to the vertebrate interferon (cytokine)-induced signaling pathway and has been shown to mediate insect anti-viral immunity as well as the mosquito defense against bacteria, fungi, and Plasmodium parasites [33–43]. Given the extensive overlap between the antibacterial, anti-parasitic, and antiviral immune responses, the microbiota can act through the immune system as a key determinant of vector susceptibility to human pathogen infection [6,7,44,45].…”

“…The entomopathogenic bacteria Bacillus thuringiensis and the fungus Beauveria bassiana have been evaluated in field trials for the control of mosquito larvae [92–94]. B. bassiana not only kills mosquitoes but also reduces susceptibility to DENV infection through immune pathway activation [43]. The use of B. bassiana for control of human disease can however raise ecological and safety concerns because the fungus will be applied in close contact to humans compared to the pervious use in agricultural application, especially for the anthropophillic mosquito Ae.…”