Monochamus alternates,the main vector beetles of invasive pinewood nematode,has established a symbiotic relationship with a native ectotrophic fungal symbiont,Sporothrix sp.1,in China.The immune response ofM.alternates to S.sp.1 in the coexistence of beetles and fungi is,however,unknown.Here,we report that immune responses ofM.alternates pupae to infection caused by ectotrophic symbiotic fungus S.sp.1 and entomopathogenic fungus Beauveria bassiana differ significantly.The S.sp.1 did not kill the beetles while B.bassiana killed all upon injection.The transcriptome results showed that the numbers of differentially expressed genes in M.alternates infected with S.sp.1 were 2-fold less than those infected with B.bassiana at 48 hours post infection.It was noticed that Toll and IMD pathways played a leading role in the beetle's immune system when infected by symbiotic fungus,but upon infection by entomopathogenic fungus,only the Toll pathway gets triggered actively.Furthermore,the beetles could tolerate the infection of symbiotic fungi by retracing their Toll and IMD pathways at 48 h.This study provided a comprehensive sequence resource ofM.alternates transcriptome for further study of the immune interactions between host and associated fungi.
Dear Editor,The pinewood nematode(PWN)Bursaphelenchus xylophilus(Steiner and Buhrer,1934)Nickle,1970,the causal agent of Pine Wilt Disease(PWD),is an invasive species known to have originated from North America,where it was not reported to cause large-scale outbreaks(Wingfield et al.,1984).Ecological conditions encountered by B.xylophilus in China are different from conditions in its native North American range.Ecological differences,together with short generation times,improve the chances that changes in
With the rapid increase of antibiotic-resistant pathogens and the decline of discovery and development of new antibiotics,there is an urgent need to exploit alternative anti-infective drugs.Fungal defensin-like peptides are emerging as a class of new source of anti-infective drugs due to their potent antibacterial activity,low toxicity,and high serum stability.Fungal genome sequencing projects combined with the development of recombinant expression techniques will accelerate the discovery of fungal defensinlike peptides.
Prof.Zhu Shunyi and his research team from the Institute of Zoology,Chinese Academy of Sciences,discovered nematode-derived drosomycin-type antifungal peptides(DTAFPs),which provides evidence for horizontal gene transfer(HGT)of a disease resistance gene between plants and ecdysozoans(Nature Communications,2014,5:3154).
