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The arms race between fungal pathogens and plant hosts involves recognition of fungal effectors to induce host immunity. Although various fungal effectors have been identified, the effector functions of ribonucleases are largely unknown. Herein, we identified a ribonuclease secreted by Verticillium dahliae (VdRTX1) that translocates into the plant nucleus to modulate immunity. The activity of VdRTX1 causes hypersensitive response (HR)-related cell death in Nicotiana benthamiana and cotton. VdRTX1 possesses a signal peptide but is unlikely to be an apoplastic effector because its nuclear localization in the plant is necessary for cell death induction. Knockout of VdRTX1 significantly enhanced V.dahliae virulence on tobacco while V.dahliae employs the known suppressor VdCBM1 to escape the immunity induced by VdRTX1. VdRTX1 homologs are widely distributed in fungi but transient expression of 24 homologs from other fungi did not yield cell death induction, suggesting that this function is specific to the VdRTX1 in V.dahliae. Expression of site-directed mutants of VdRTX1 in N.benthamiana leaves revealed conserved ligand-binding sites that are important for VdRTX1 function in inducing cell death. Thus, VdRTX1 functions as a unique HR-inducing effector in V.dahliae that contributes to the activation of plant immunity.

Additional file 2: Figure S1. Analysis of the cell death suppression activities of 120 VdSCPs in Nicotiana benthamiana leaves. Figure S2. Analysis of the broad-spectrum cell death suppression activities of CFEM-containing VdSCPs in Nicotiana benthamiana leaves. Figure S3. Analysis of signal peptide function and subcellular localization of VdSCP76 and VdSCP77. Figure S4. Polymerase chain reaction (PCR) analysis of gene deletion transformants of CFEM-containing VdSCPs from V. dahliae. Figure S5. Polymerase chain reaction (PCR) analysis of gene complementation transformants. Figure S6. Identification of the immunity suppression activity of VdSCP76 and VdSCP77 in Nicotiana benthamiana. Figure S7. Immunoblotting analysis of proteins in Nicotiana benthamiana leaves transiently expressing VdEG1 in the suppression experiment. Figure S8. Pathogenicity assay of double gene deletion of VdSCP76 and VdSCP77 strains on cotton. Figure S9. Functional diversification analysis of CFEM-containing VdSCPs family members. Figure S10. Gene expression of CFEM-containing VdSCPs family members during infection of cotton roots. Figure S11. Analysis of defense related-gene expression level. Figure S12. The fungal biomass and disease index of indicated strains on cotton. Figure S13. Functional analyses of conserved asparagine residues in the CFEM domain-containing members from Verticillium dahliae. Figure S14. Gene expression level of CFEM-containing VdSCPs under iron starvation and ferric ion conditions. Figure S15. Functional dissection Asp-type and Asn-type CFEM-containing secretory proteins from Fusarium oxysporum and Magnaporthe oryzae.

Additional file 1: Supplementary Figure 1. Kaplan-Meier analysis for the cumulative incidence of dementia with log-rank test. Supplementary Figure 2. The survival curves of cumulative incidence of dementia and competing risk event for death. Supplementary Table 1. Association of cancer with dementia risk after additional adjustment for cognitive function. Supplementary Table 2. Association of site-specific cancers with dementia and its subtypes. Supplementary Table 3. Association of specific cancer sites with ACD, AD, and VD by ApoE4 status and BMI.

Additional file 1: Table S1. Compounds used for characterization of Agrotis segetum ionotropic receptors (IRs), including their purities and source information. Table S2. Primers used in qPCR. Table S3. Primers used in gene cloning. Fig. S1. Additional representative FISH images.

Additional file 2. Amino acid sequences of AsegIRs.

Simple Summary Moths typically rely on sex pheromone communication to find a mate. This involves the production of species-specific sex pheromones by females (the signaller) and the corresponding selective detection by conspecific males (the receiver). A key question in the evolution of the pheromone communication system is how the female signals can diversify and still be tracked by the receivers over the process of speciation. The genus Ostrinia, which comprises 20 species worldwide including several well-recognised agricultural pests, is an attractive model in the study of the evolution of sex pheromone communication, as the closely related species and strains provide an ideal example of ongoing speciation. This review presents a comprehensive overview of the research on pheromone communication in different Ostrinia species over the past four decades, from the identity and biosynthesis of pheromones in the females to the molecular and neuronal basis of the pheromone perception in males. The evolutionary insights from these studies are discussed and the directions for future research are outlined. Abstract It remains a conundrum in the evolution of sexual communication how the signals and responses can co-ordinate the changes during speciation. The genus Ostrinia contains several closely related species as well as distinctive strains with pheromone polymorphism and represents an example of ongoing speciation. Extensive studies in the genus, especially in the species the European corn borer O. nubilalis (ECB), the Asian corn borer O. furnacalis (ACB) and the adzuki bean borer O. scapulalis (ABB), have provided valuable insights into the evolution of sex pheromone communication. This review presents a comprehensive overview of the research on pheromone communication in different Ostrinia species over the past four decades, including pheromone identification and biosynthesis, the ligand profiles of pheromone receptor (PR) genes, the physiology of peripheral olfactory sensory neurons (OSNs) and the projection pattern to the antennal lobe. By integrating and comparing the closely related Ostrinia species and strains, it provides an evolutionary perspective on the sex pheromone communication in moths in general and also outlines the outstanding questions that await to be elucidated by future studies.