In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.
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Question: IFITM3 restricts cellular infection by multiple important viral pathogens, and is particularly critical for the innate immune response against influenza virus. Expression of IFITM3 expands acidic endolysosomal compartments and prevents fusion of endocytosed viruses, leading to their degradation. This small, 133 amino acid, antiviral protein is controlled by at least four distinct post-translational modifications. Positive regulation of IFITM3 antiviral activity is provided by Spalmitoylation, while negative regulatory mechanisms include lysine ubiquitination, lysine methylation and tyrosine phosphorylation. Herein, we describe specific insights into IFITM3 trafficking and activity that were provided by studies of IFITM3 post-translational modifications, and discuss evidence suggesting that IFITM3 adopts multiple membrane topologies involving at least one intramembrane domain in its antivirally active conformation.

Answer: Regulation of the trafficking and antiviral activity of IFITM3 by post-translational modifications


Question: Duck plague virus (DPV) is a representative pathogen transmitted among aquatic animals that causes gross lesions and immune inhibition in geese and ducks. The mechanism of organ tropism and innate immune evasion of DPV has not been completely deciphered due to a lack of cell models to study the innate immune manipulation and pathogenicity of aquatic viruses. In the present study, we isolated five types of duck primary cells [duck embryo fibroblasts (DEFs), neurons, astrocytes, peripheral blood mononuclear cells (PBMCs), and monocytes/macrophages] to identify appropriate cell models for DPV, using tropism infection and innate immunologic assays. Cells responded differently to stimulation with DNA viruses or RNA virus analogs. DPV infection exhibited broad tropism, as the recombinant virulent strain (CHv-GFP) infected DEFs, neurons, astrocytes, and monocytes/macrophages, but not the PBMCs, as the expression of EGFP was negligible. The basal levels of innate immunity molecules were highest in monocytes/macrophages and lower in DEFs and astrocytes. Conversely, the titer and genomic copy number of the attenuated virus strain was higher in DEFs and astrocytes than in neurons and monocytes/macrophages. The titer and genomic copy number of the attenuated virus strain were higher compared with the virulent strain in DEFs, neurons, and astrocytes. The innate immune response was not significantly induced by either DPV strain in DEFs, neurons, or astrocytes. The virulent strain persistently infected monocytes/macrophages, but the attenuated strain did so abortively, and this was accompanied by the phenomenon of innate immune inhibition and activation by the virulent and attenuated strains, respectively. Blockage of IFNAR signaling promoted replication of the attenuated strain. Pre-activation of IFNAR signaling inhibited infection by the virulent strain. The selection assay results indicated that induction of innate immunity plays an essential role in controlling DPV infection, and monocytes/macrophages are an Tian et al. Duck Primary Cells Infection Models important cell model for further investigations. Our study provided practical methods for isolating and culturing duck primary cells, and our results will facilitate further investigations of organ tropism, innate immune responses, latent infection, and the effectiveness of antiviral drugs for treating DPV and potentially other aerial bird pathogens.

Answer: Isolation and Selection of Duck Primary Cells as Pathogenic and Innate Immunologic Cell Models for Duck Plague Virus


Question: The adhesion of microbial pathogens to host cells is mediated by adhesins. Experimental methods used for characterizing adhesins are time-consuming and demand large resources. The availability of specialized software can rapidly aid experimenters in simplifying this problem. We have employed 105 compositional properties and artificial neural networks to develop SPAAN, which predicts the probability of a protein being an adhesin (P ad ). Results: SPAAN had optimal sensitivity of 89% and specificity of 100% on a defined test set and could identify 97.4% of known adhesins at high P ad value from a wide range of bacteria. Furthermore, SPAAN facilitated improved annotation of several proteins as adhesins. Novel adhesins were identified in 17 pathogenic organisms causing diseases in humans and plants. In the severe acute respiratory syndrome (SARS) associated human corona virus, the spike glycoprotein and nsps (nsp2, nsp5, nsp6 and nsp7) were identified as having adhesin-like characteristics. These results offer new lead for rapid experimental testing.

Answer:
SPAAN: a software program for prediction of adhesins and adhesin-like proteins using neural networks