The immune evasion protein US3 of human cytomegalovirus binds to and arrests MHC class I molecules in the endoplasmic reticulum (ER). However, substantial amounts of class I molecules still escape ...US3-mediated ER retention, suggesting that not all class I alleles are affected equally by US3. Here, we identify tapasin inhibition as the mechanism of MHC retention by US3. US3 directly binds tapasin and inhibits tapasin-dependent peptide loading, thereby preventing the optimization of the peptide repertoire presented by class I molecules. Due to the allelic specificity of tapasin toward class I molecules, US3 affects only class I alleles that are dependent on tapasin for peptide loading and surface expression. Accordingly, tapasin-independent class I alleles selectively escape to the cell surface.
In a randomized trial involving patients with non–small-cell lung cancer with mutant EGFR (T790M) in whom a tyrosine kinase inhibitor had failed, osimertinib was associated with significantly longer ...progression-free survival than platinum therapy plus pemetrexed.
Among patients with advanced non–small-cell lung cancer with a mutant epidermal growth factor receptor (EGFR), EGFR tyrosine kinase inhibitors (TKIs) are the standard first-line therapy.
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Despite high tumor response rates with first-line EGFR-TKIs, disease progresses in a majority of patients after 9 to 13 months of treatment.
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At the time of progression, approximately 60% of patients (regardless of race or ethnic background) are found to have a p.Thr790Met point mutation (T790M) in the gene encoding EGFR.
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The presence of the T790M variant reduces binding of first-generation or second-generation EGFR-TKIs to the ATP-binding pocket of EGFR, thereby reducing . . .
The main focus of this study was to gain an overall view of Pseudomonas putida 06909 genes involved in the Pseudomonas-Phytophthora interaction as a biological control mechanism, and to understand ...the roles of these genes. Sixteen Ps. putida genes with increased expression on Phytophthora mycelial surfaces were identified using in vivo expression technology (IVET) screening. Sequence analysis of these Phytophthora mycelium-induced (pmi) genes revealed that many of them display similarity to genes known or predicted to be involved in carbohydrate catabolism, energy metabolism, amino acid/nucleotide metabolism, and membrane transport processes. Disruption of three pmi genes encoding succinate semialdehyde dehydrogenase, a dicarboxylic acid transporter, and glyceraldehyde-3-phosphate dehydrogenase showed significant phenotypic differences involved in the colonization processes, including motility, biofilm formation on abiotic surfaces, colony morphology, and competitive colonization of fungal mycelia. All three of these pmi genes were induced by glycogen and other substances, such as organic acids and amino acids utilized by Ps. putida. The IVET screening and mutant characterization can be used to identify bacterial genes that are induced on the mycelial surface and provide insight into the possible mechanisms of mycelial colonization by this bacterium. The IVET screening through a bacterial genome library might be a huge task. However, because the genes involved in direct interaction with Phytophthora and in bacterial adaptation can be identified, the IVET system will be a valuable tool in studying biocontrol bacteria at the molecular and ecological levels.
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