Insect vectors are required for the transmission of many species of parasitic nematodes, but the mechanisms by which the vectors and nematodes coordinate their life cycles are poorly understood. Here, we report that ascarosides, an evolutionarily conserved family of nematode pheromones, are produced not only by a plant-parasitic nematode, but also by its vector beetle. The pinewood nematode and its vector beetle cause pine wilt disease, which threatens forest ecosystems world-wide. Ascarosides secreted by the dispersal third-stage nematode L_III larvae promote beetle pupation by inducing ecdysone production in the beetle and up-regulating ecdysone-dependent gene expression. Once the beetle develops into the adult stage, it secretes ascarosides that attract the dispersal fourth-stage nematode L_IV larvae, potentially facilitating their movement into the beetle trachea for transport to the next pine tree. These results demonstrate that ascarosides play a key role in the survival and spread of pine wilt disease.

Invasive pathogen–insect symbioses have been extensively studied in many different ecological niches. Whether the damage of symbioses in different introduced regions might be influenced by other microorganisms has, however, received little attention. Eight years of field data showed that the varied levels of the nematode and beetle populations and infested trees of the invasiveBursaphelenchus xylophilus–Monochamus alternatussymbiosis were correlated with patterns in the isolation frequencies of ophiostomatoid fungi at six sites, while the laboratory experiments showed that the nematode produced greater numbers of offspring with a female‐biased sex ratio and developed faster in the presence of one native symbiotic ophiostomatoid fungus,Sporothrixsp. 1. Diacetone alcohol (DAA) from xylem inoculated withSporothrixsp. 1 inducedB. xylophilusto produce greater numbers of offspring. Its presence also significantly increased the growth and survival rate ofM. alternatus, and possibly explains the prevalence of the nematode–vector symbiosis whenSporothrixsp. 1 was dominant in the fungal communities. Studying the means by which multispecies interactions contributed to biogeographical dynamics allowed us to better understand the varied levels of damage caused by biological invasion across the invaded range.

In viruses, posttranslational modifications (PTMs) are essential for their life cycle. Recognizing viral PTMs is very important for a better understanding of the mechanism of viral infections and finding potential drug targets. However, few studies have investigated the roles of viral PTMs in virus–human interactions using comprehensive viral PTM datasets. To fill this gap, we developed the first comprehensive viral posttranslational modification database (VPTMdb) for collecting systematic information of PTMs in human viruses and infected host cells. The VPTMdb contains 1240 unique viral PTM sites with 8 modification types from 43 viruses (818 experimentally verified PTM sites manually extracted from 150 publications and 422 PTMs extracted from SwissProt) as well as 13 650 infected cells’ PTMs extracted from seven global proteomics experiments in six human viruses. The investigation of viral PTM sequences motifs showed that most viral PTMs have the consensus motifs with human proteins in phosphorylation and five cellular kinase families phosphorylate more than 10 viral species. The analysis of protein disordered regions presented that more than 50% glycosylation sites of double-strand DNA viruses are in the disordered regions, whereas single-strand RNA and retroviruses prefer ordered regions. Domain–domain interaction analysis indicating potential roles of viral PTMs play in infections. The findings should make an important contribution to the field of virus–human interaction. Moreover, we created a novel sequence-based classifier named VPTMpre to help users predict viral protein phosphorylation sites. VPTMdb online web server (http://vptmdb.com:8787/VPTMdb/) was implemented for users to download viral PTM data and predict phosphorylation sites of interest.