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Abstract Objective Autophagy is a highly conserved intracellular degradation pathway. Many picornaviruses induce autophagy to benefit viral replication, but an understanding of how autophagy occurs remains incomplete. In this study, we explored whether coxsackievirus B3 (CVB3) infection induced autophagy through endoplasmic reticulum (ER) stress. Methods In CVB3-infected HeLa cells, the specific molecules of ER stress and autophagy were detected using Western blotting, reverse transcription polymerase chain reaction (RT-PCR), and confocal microscopy. Then PKR-like ER protein kinase (PERK) inhibitor, inositol-requiring protein-1 (IRE1) inhibitor, or activating transcription factor-6 (ATF6) inhibitor worked on CVB3-infected cells, their effect on autophagy was assessed by Western blotting for detecting microtubule-associated protein light chain 3 (LC3). Results CVB3 infection induced ER stress, and ER stress sensors PERK/eIF2α, IRE1/XBP1, and ATF6 were activated. CVB3 infection increased the accumulation of green fluorescent protein (GFP)-LC3 punctuation and induced the conversion from LC3-I to phosphatidylethanolamine-conjugated LC3-1 (LC3-II). CVB3 infection still decreased the expression of mammalian target of rapamycin (mTOR) and p-mTOR. Inhibition of PERK, IRE1, or ATF6 significantly decreased the ratio of LC3-II to LC3-I in CVB3-infected HeLa cells. Conclusion CVB3 infection induced autophagy through ER stress in HeLa cells, and PERK, IRE1, and ATF6a pathways participated in the regulation of autophagy. Our data suggested that ER stress may inhibit mTOR signaling pathway to induce autophagy during CVB3 infection. [ABSTRACT FROM AUTHOR]

To understand the potential causes of laboratory-acquired infections and to provide possible solutions that would protect laboratory personnel, samples from a viral laboratory were screened to determine the main sources of contamination with six subtypes of Rhinovirus. Rhinovirus contamination was found in the gloves, cuffs of protective wear, inner surface of biological safety cabinet (BSC) windows, and trash handles. Remarkably, high contamination was found on the inner walls of the centrifuge and the inner surface of centrifuge tube casing in the rotor. Spilling infectious medium on the surface of centrifuge tubes was found to contribute to contamination of centrifuge surfaces. Exposure to sodium hypochlorite containing no less than 0.2 g/L available chlorine decontaminated the surface of the centrifuge tubes from Rhinovirus after 2 min. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to identify internal ribosome entry sites (IRESs) in the open reading frame (ORF) of the Coxsackievirus B3 (CVB3) genome., Methods: The sequences of P1, P2, or P3 of the CVB3 genome or the truncated sequences from each antithymocyte globulin (ATG) to the end of the P1, P2, or P3 gene were inserted into the pEGFP-N1 vector. After transfection, possible IRES-dependent green fluorescent protein (GFP)-fused proteins were detected by anti-GFP western blotting. The sequences of possible IRESs were inserted into specific Fluc/Rluc bicistronic vectors, in which the potential IRESs were determined according to the Fluc/Rluc activity ratio. Expression of Fluc and Rluc mRNA of the bicistronic vector was detected by RT-qPCR., Results: After transfection of full length or truncated sequences of the P1, P2, or P3 plasmids, six GFP-fused protein bands in P1, six bands in P2 and nine bands in P3 were detected through western blotting. Two IRESs in VP2 (1461-1646 nt) and VP1 (2784-2983 nt) of P1; one IRES in 2C (4119-4564 nt) of P2; and two IRESs in 3C (5634-5834 nt) and 3D (6870-7087 nt) of P3 were identified according to Fluc/Rluc activity ratio. The cryptic promoter was also excluded by RT-qPCR., Conclusion: Five IRESs are present in the CVB3 coding region., (Copyright © 2022 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.)

Objective: To explore the association of -1195G > A genetic variant in the promoter region of cyclooxygenase 2 genetic (COX2) with the genetic susceptibility of lung cancer and its interaction with smoking., Methods: Totally, 956 lung cancer patients recruited between January 2000 and December 2008 at Cancer Hospital, Chinese Academy of Medical Science as the case group, and 994 frequency-matched controls were randomly selected from a pool of cancer-free subjects recruited from a nutritional survey. All subjects were ethnic Han Chinese. There was no sex, age restrictions. Case group and control group were matched. Informed consent was obtained and 2 ml peripheral blood was collected from each subject. All samples were genotyped by polymerase chain reaction-restriction fragment length polymorphism method, smoking status of the subjects was surveyed.While the OR and 95% CI were estimated by logistic regression to evaluate the relation of COX2 -1195G > A variant and the risk of lung cancer., Results: The genetic allele COX2 -1195AA of control group and case group were 24.9% (247/994) and 28.3% (271/956) . Case-control analysis showed an increased risk of developing lung cancer for -1195AA genotype carriers (OR = 1.36, 95% CI: 1.03-1.79), compared with -1195GG carriers. When stratified by smoking status, the significant increased risk of lung cancer was found among smokers with COX2-1195AA genotype, with the OR (95%CI) was 1.56 (1.08-2.25); while among non-smokers, difference of lung cancer risk was not found among different genotypes (OR = 1.17; 95%CI: 0.77-1.61). Among heavy smokers (pack-year >20), -1195AA and -1195AG genotype carriers have significant increased risk of lung cancer with 1.85 (1.16-2.95) and 1.62(1.08-2.43) of OR (95%CI), respectively; among light smokers (pack-year ≤ 20), the OR (95%CI) of lung cancer risk in -1195AG and -1195AA genotype carriers were 0.78 (0.47-1.30) and 1.08 (0.60-1.94), respectively., Conclusion: Genetic polymorphism in the promoter of COX2 gene interacting with smoking factor plays an important role in the development of lung cancer.

To study the impact of the enterovirus 71(EV71) on the nuclear transport mechanism,The pGFP-NLS vector with nuclear location signal(NLS) was constructed, RD cells transfected by the pGFP-NLS vector were inoculated with the EV71 or cotransfected by EV71-2A vector. The results showed that GFP protein with NLS was expressed in the cytoplasm due to the inhibition of nuclear transport. In order to further study the mechanism of the EV71 to prevent nuclear transport,Nup62 was detected by Western blotting after RD cells were infected with EV71 or transfected by EV71-2A vector. The results showed that decreased expression of Nup62 could be detected after infection with EV71 and transfection by EV71-2A vector. This study demonstrates that the cleavage of Nup62 by EV71 2A protease may be the mechanism of nuclear transport inhibition.

Objective: To investigate both PrP and PrP106-126 peptide effect on 14-3-3beta dimeration., Methods: 14-3-3beta were incubated with different does recombinant PrP or PrP106-126 peptide, both 14-3-3beta dimer and polymer were separated 15% non-denaturing polyacrylamide gel electrophoresis (PAGE) and the 14-3-3 dimers were evaluated using 14-3-3beta-specific Western blotting. And then,14-3-3beta dimeration buffer were incubated with different does recombinant PrP and 250 micromol/L PrP106-126 peptide, 14-3-3beta dimer and polymer were detected by above methods. Cellular 14-3-3 dimer were also detected after PrP106-126 peptide were added to HeLa cell for 8 hours., Results: Recombinant full-length PrP facilitated the dimerization of 14-3-3beta and PrP106-126 disturbed 14-3-3beta dimeration as both have dose dependence effect. PrP antagonized PrP106-126-induced 14-3-3beta dimer with PrP protein increase in vitro. Cellular 14-3-3 dimerization also decreased after treatment of peptide PrP106-126 on HeLa cells for 8 hours., Conclusion: [corrected] Dimerization process of 14-3-3beta was promoted by full-length PrP (PrP23-231) but inhibited by peptide PrP106-126 in vitro. PrP agonized PrP106-126-induced inhibition of 14-3-3 dimeration. PrP106-126 inhibited cellular 14-3-3 dimerization.

To investigate changes of 14-3-3beta from apoptosis induced by PrP106-126 polypeptide, HeLa cell was incubated with PrP106-126 for 4h or 8h. Nucleus changes and the expression of PARP were detected differently by Hoechst staining and Western blotting. Expressing of protein and mRNA from 14-3-3beta was determined by Western blotting and Real-time PCR. The results show that typical nucleus pyknosis and chip of apoptosis and degradation of PARP were induced by PrP106-126 peptide in HeLa cells. Degradation of 14-3-3beta appeared in apoptosis groups induced by PrP106-126 peptide. However, 14-3-3beta mRNA did not display any changes in apoptosis groups. This study indicated that degradation of antiapoptosis protein 143-3beta induced by PrP106-126 peptide may be one of pathogenesis mechanism of prion disease.

Objective: To investigate human enterovirus 71 (EV71) resistance to type I interferon induced antiviral effect., Methods: After type I interferons (alpha, beta) were incubated with HeLa cells, recombinant type I herpes simple virus (HSV-1) with green fluorescent protein (GFP) was inoculated onto the HeLa cells. HSV-1 proliferation was observed by GFP expression and PCR. After EV71 was inoculated onto HeLa cells incubated with the same quantity of interferon, proliferation of EV71 were detected by RT-PCR of 2A gene., Results: Recombinant HSV-1 GFP expression and viral DNA replication obviously decreased in HeLa cells incubated with type I interferon (alpha, beta). However, EV71 effectively proliferated in the interferon irritated HeLa cell by RT-PCR., Conclusion: HeLa cell irritated by type I interferon (alpha, beta) produced antiviral substance that inhibits HSV-1 proliferation. EV71 resisted the antiviral substance induced by type I interferon and could significantly replicate in the HeLa cells.