Project description:Venom injected at oviposition is crucial for successful reproduction in most parasitoid wasp species (Moreau & Asgari 2015; Poirié et al. 2014). The venom of the pea aphid parasitoid Aphidius ervi was analyzed previously using a combined transcriptomic and proteomic approach (Colinet et al. 2014) and we applied similar methods here to compare the venom composition in Lysiphlebus fabarum, that also used the pea aphid as host. Venom was extracted from the L. fabarum venom gland and analyzed using 1D gel electrophoresis and mass spectrometry. A total of 35 L. fabarum proteins were identified as putative venom proteins using these results combined with available transcriptomic data (Dennis et al. 2017) and the genomic data.
Project description:In vivo, HIV-1 replicates within tissues, yet the impact of three-dimensional (3D) environments on viral spread remains poorly understood. We previously showed that collagen-rich 3D extracellular matrix (ECM) imposes an Environmental Restriction to cell-free Virus Infectivity (ERVI). Here, we demonstrate that ERVI is mediated by adhesive ECM components assembled into tissue-like scaffolds. Transient interactions with collagen fibers rapidly diminish virion infectivity across diverse primary strains by impairing virus fusogenicity. Notably, collagen-experienced particles also induce a distinct antiviral transcriptional program and strong pro-inflammatory cytokine secretion in monocyte-derived macrophages. Mechanistically, collagen contact induces conformational changes in the viral glycoprotein Env, enhances its interaction with toll-like receptor 2 (TLR2), and promotes trafficking into TLR8-positive endosomes, thereby amplifying innate immune sensing. Thus, ERVI acts through a dual mechanism: reducing virion fusogenicity while increasing innate immune detection. These findings identify the biophysical properties of the ECM as a tissue-intrinsic arm of antiviral innate immunity.