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The fast envelope stress responses play a key role in the transmission and pathogenesis of Yersinia enterocolitica, one of the most common foodborne pathogens. Our previous study showed that deletion of the waaF gene, essential for the biosynthesis of lipopolysaccharide (LPS) core polysaccharides, led to the formation of a truncated LPS structure and induced cell envelope stress. This envelope stress may disturb the intracellular signal transduction, thereby affecting the physiological functions of Y. enterocolitica. In this study, truncated LPS caused by waaF deletion was used as a model of envelope stress in Y. enterocolitica. We investigated the mechanisms of envelope stress responses and the cellular functions affected by truncated LPS. Transcriptome analysis and phenotypic validation showed that LPS truncation reduced flagellar assembly, bacterial chemotaxis, and inositol phosphate metabolism, presenting lower pathogenicity and viability both in vivo and in vitro environments. Further 4D label-free phosphorylation analysis confirmed that truncated LPS perturbed multiple intracellular signal transduction pathways. Specifically, a comprehensive discussion was conducted on the mechanisms by which chemotactic signal transduction and Rcs system contribute to the inhibition of chemotaxis. Finally, the pathogenicity of Y. enterocolitica with truncated LPS was evaluated in vitro using IPEC-J2 cells as models, and it was found that truncated LPS exhibited reduced adhesion, invasion, and toxicity of Y. enterocolitica to IPEC-J2 cells. Our research provides an understanding of LPS in the regulation of Y. enterocolitica viability and pathogenicity and, thus, opening new avenues to develop novel food safety strategies or drugs to prevent and control Y. enterocolitica infections. Key points: • Truncated LPS reduces flagellar assembly, chemotaxis, and inositol phosphate metabolism in Y. enterocolitica. • Truncated LPS reduces adhesion, invasion, and toxicity of Y. enterocolitica to IPEC-J2 cells. • Truncated LPS regulates intracellular signal transduction of Y. enterocolitica. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate the mechanism of miR-29a-3p in regulating endometrial cancer (EC) progression.Methods: A total of 72 EC patients were enrolled. EC cells were transfected. Cells proliferation, cloning ability, migration and invasion were researched by MTT assay, colony formation experiment, cell scratch test and Transwell experiment respectively. Dual-luciferase reporter assay was performed. Xenograft experiment was conducted using nude mice. miR-29a-3p, VEGFA, CDC42, PAK1 and p-PAK1 expression in cells/tissues was investigated by qRT-PCR and Western blot.Results: miR-29a-3p expression was aberrantly reduced in EC patients, which was associated with poor outcome. miR-29a-3p inhibited EC cells proliferation, cloning formation, migration and invasion (P <  0.05 or P <  0.01 or P <  0.001). miR-29a-3p inhibited CDC42/PAK1 signaling pathway activity in EC cells (P <  0.01). VEGFA expression was directly inhibited by miR-29a-3p. miR-29a-3p suppressed EC cells malignant phenotype in vitro and growth in vivo by targeting VEGFA/CDC42/PAK1 signaling pathway (P < 0.05 or P < 0.01).Conclusion: miR-29a-3p inhibits EC cells proliferation, migration and invasion by targeting VEGFA/CDC42/PAK1 signaling pathway. [ABSTRACT FROM AUTHOR]