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Host–Pathogen Interaction

A special issue of International Journal of Molecular Sciences (ISSN 1422-0067). This special issue belongs to the section "Molecular Microbiology".

Deadline for manuscript submissions: closed (30 November 2019) | Viewed by 38749

Special Issue Editor

Special Issue Information

Dear Colleagues,

Microorganisms can interact with higher organisms in many different ways, e.g., beneficially as symbionts, indifferently as commensals or harmfully as pathogens. Today, a wide variety of molecular and cell biology tools, including advanced microscopy and -omics techniques, allow us to study these interactions at a molecular level. This Special Issue will deal with pathogenic bacteria and unicellular eukaryotes and their interaction with plants, animals, and humans. Reviews and research articles focusing on either the pathogen’s or the host’s side are welcome.

Prof. Andreas Burkovski
Guest Editor

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Published Papers (12 papers)

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17 pages, 3513 KiB  
Article
Pic-Producing Escherichia coli Induces High Production of Proinflammatory Mediators by the Host Leading to Death by Sepsis
by Itaynara L. Dutra, Lorena G. Araújo, Raissa G. Assunção, Yago A. Lima, Johnny R. Nascimento, André A. M. Vale, Patrícia C. S. Alves, Liana O. Trovão, Ana Carolina M. Santos, Rosa M. Silva, Lucilene A. Silva, Márcia C. G. Maciel, Eduardo M. de Sousa, Waldir P. Elias, Flávia R. F. Nascimento and Afonso G. Abreu
Int. J. Mol. Sci. 2020, 21(6), 2068; https://doi.org/10.3390/ijms21062068 - 18 Mar 2020
Cited by 7 | Viewed by 3079
Abstract
Escherichia coli is an important pathogen responsible for a variety of diseases. We have recently shown that Pic, a serine protease secreted by E. coli, mediates immune evasion by the direct cleavage of complement molecules. The aim of this study was to [...] Read more.
Escherichia coli is an important pathogen responsible for a variety of diseases. We have recently shown that Pic, a serine protease secreted by E. coli, mediates immune evasion by the direct cleavage of complement molecules. The aim of this study was to investigate the action of a Pic-producing bacteria in a murine model of sepsis. Mice were infected with Pic-producing E. coli (F5) or F5∆pic mutant. Animal survival was monitored for five days, and a subset of mice was euthanized after 12 h for sample acquisition. The inoculation of Pic-producing bacteria induced 100% death within 24 h. The colony forming units count in the organs was significantly higher in F5. Hematological analysis showed a decrease of total leukocytes. Nitric oxide and cytokines were detected in serum, as well as on peritoneal lavage of the F5 group in higher levels than those detected in the other groups. In addition, immunophenotyping showed a decrease of activated lymphocytes and macrophages in the F5 group. Therefore, Pic represents an important virulence factor, allowing the survival of the bacterium in the bloodstream and several organs, as well as inducing a high production of proinflammatory mediators by the host, and concomitantly a cellular immunosuppression, leading to sepsis and death. Full article
(This article belongs to the Special Issue Host–Pathogen Interaction)
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13 pages, 1954 KiB  
Article
Heterologous Expression of CLIBASIA_03915/CLIBASIA_04250 by Tobacco Mosaic Virus Resulted in Phloem Necrosis in the Senescent Leaves of Nicotiana benthamiana
by Hui Li, Xiaobao Ying, Lina Shang, Bryce Redfern, Nicholas Kypraios, Xuejun Xie, FeiFei Xu, Shaopeng Wang, Jinghua Zhang, Hongju Jian, Hongtao Yu and Dianqiu Lv
Int. J. Mol. Sci. 2020, 21(4), 1414; https://doi.org/10.3390/ijms21041414 - 19 Feb 2020
Cited by 12 | Viewed by 3161
Abstract
Huanglongbing (HLB), also known as citrus greening, is the most notorious citrus disease worldwide. Candidatus Liberibacter asiaticus (CaLas) is a phloem-restricted bacterium associated with HLB. Because there is no mutant library available, the pathogenesis of CaLas is obscure. In this [...] Read more.
Huanglongbing (HLB), also known as citrus greening, is the most notorious citrus disease worldwide. Candidatus Liberibacter asiaticus (CaLas) is a phloem-restricted bacterium associated with HLB. Because there is no mutant library available, the pathogenesis of CaLas is obscure. In this study, we employed tobacco mosaic virus (TMV) to express two mature secretion proteins CLIBASIA_03915 (m03915) and CLIBASIA_04250 (m04250) in Nicotiana benthamiana (N. benthamiana). Phloem necrosis was observed in the senescent leaves of N. benthamiana that expressed the two low molecular weight proteins, while no phloem necrosis was observed in the plants that expressed the control, green fluorescent protein (GFP). Additionally, no phloem necrosis was observed in the senescent leaves of N. benthamiana that expressed the null mutation of m03915 and frameshifting m04250. The subcellular localizations of m03915 and m04250 were determined by fusion with GFP using confocal microscopy. The subcellular localization of m03915 was found to be as free GFP without a nuclear localization sequence (NLS). However, m04250 did have an NLS. Yeast two-hybrid (Y2H) was carried out to probe the citrus proteins interacting with m03915 and m04250. Six citrus proteins were found to interact with m03915. The identified proteins were involved in the metabolism of compounds, transcription, response to abiotic stress, ubiquitin-mediated protein degradation, etc. The prey of m04250 was involved in the processing of specific pre-mRNAs. Identification of new virulence factors of CaLas will give insight into the pathogenesis of CaLas, and therefore, it will eventually help develop the HLB-resistant citrus. Full article
(This article belongs to the Special Issue Host–Pathogen Interaction)
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16 pages, 2181 KiB  
Article
Flavescence Dorée Phytoplasma Has Multiple ftsH Genes that Are Differentially Expressed in Plants and Insects
by Camille Jollard, Xavier Foissac, Delphine Desqué, Frédérique Razan, Christophe Garcion, Laure Beven and Sandrine Eveillard
Int. J. Mol. Sci. 2020, 21(1), 150; https://doi.org/10.3390/ijms21010150 - 24 Dec 2019
Cited by 8 | Viewed by 3015
Abstract
Flavescence dorée (FD) is a severe epidemic disease of grapevines caused by FD phytoplasma (FDP) transmitted by the leafhopper vector Scaphoideus titanus. The recent sequencing of the 647-kbp FDP genome highlighted an unusual number of genes encoding ATP-dependent zinc proteases FtsH, which [...] Read more.
Flavescence dorée (FD) is a severe epidemic disease of grapevines caused by FD phytoplasma (FDP) transmitted by the leafhopper vector Scaphoideus titanus. The recent sequencing of the 647-kbp FDP genome highlighted an unusual number of genes encoding ATP-dependent zinc proteases FtsH, which have been linked to variations in the virulence of “Candidatus Phytoplasma mali” strains. The aims of the present study were to predict the FtsH repertoire of FDP, to predict the functional domains and topologies of the encoded proteins in the phytoplasma membrane and to measure the expression profiles in different hosts. Eight complete ftsH genes have been identified in the FDP genome. In addition to ftsH6, which appeared to be the original bacterial ortholog, the other seven gene copies were clustered on a common distinct phylogenetic branch, suggesting intra-genome duplication of ftsH. The expression of these proteins, quantified in plants and insect vectors in natural and experimental pathosystems, appeared to be modulated in a host-dependent manner. Two of the eight FtsH C-tails were predicted by Phobius software to be extracellular and, therefore, in direct contact with the host cellular content. As phytoplasmas cannot synthesize amino acids, our data raised questions regarding the involvement of FtsH in the adaptation to hosts via potentially enhanced recycling of phytoplasma cellular proteins and host protein degradation. Full article
(This article belongs to the Special Issue Host–Pathogen Interaction)
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20 pages, 5979 KiB  
Article
Quantitative Proteomic Analysis Uncovers the Mediation of Endoplasmic Reticulum Stress-Induced Autophagy in DHAV-1-Infected DEF Cells
by Jingjing Lan, Ruihua Zhang, Honglei Yu, Jingyu Wang, Wenxiang Xue, Junhao Chen, Shaoli Lin, Yu Wang, Zhijing Xie and Shijin Jiang
Int. J. Mol. Sci. 2019, 20(24), 6160; https://doi.org/10.3390/ijms20246160 - 06 Dec 2019
Cited by 11 | Viewed by 2760
Abstract
Autophagy is a tightly regulated catabolic process and is activated in cells in response to stress signals. Despite extensive study, the interplay between duck hepatitis A virus type 1 (DHAV-1) and the autophagy of host cells is not clear. In this study, we [...] Read more.
Autophagy is a tightly regulated catabolic process and is activated in cells in response to stress signals. Despite extensive study, the interplay between duck hepatitis A virus type 1 (DHAV-1) and the autophagy of host cells is not clear. In this study, we applied proteomics analysis to investigate the interaction mechanism between DHAV-1 and duck embryo fibroblast (DEF) cells. In total, 507 differentially expressed proteins (DEPs) were identified, with 171 upregulated proteins and 336 downregulated proteins. The protein expression level of heat shock proteins (Hsps) and their response to stimulus proteins and zinc finger proteins (ZFPs) were significantly increased while the same aspects of ribosome proteins declined. Bioinformatics analysis indicated that DEPs were mainly involved in the “response to stimulus”, the “defense response to virus”, and the “phagosome pathway”. Furthermore, Western blot results showed that the conversion of microtubule-associated protein 1 light chain 3-I (LC3-I) to the lipidation form of LC3-II increased, and the conversion rate decreased when DEF cells were processed with 4-phenylbutyrate (4-PBA). These findings indicated that DHAV-1 infection could cause endoplasmic reticulum (ER) stress-induced autophagy in DEF cells, and that ER stress was an important regulatory factor in the activation of autophagy. Our data provide a new clue regarding the host cell response to DHAV-1 and identify proteins involved in the DHAV-1 infection process or the ER stress-induced autophagy process. Full article
(This article belongs to the Special Issue Host–Pathogen Interaction)
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19 pages, 3526 KiB  
Article
Dual RNA Sequencing of Vitis vinifera during Lasiodiplodia theobromae Infection Unveils Host–Pathogen Interactions
by Micael F. M. Gonçalves, Rui B. Nunes, Laurentijn Tilleman, Yves Van de Peer, Dieter Deforce, Filip Van Nieuwerburgh, Ana C. Esteves and Artur Alves
Int. J. Mol. Sci. 2019, 20(23), 6083; https://doi.org/10.3390/ijms20236083 - 03 Dec 2019
Cited by 28 | Viewed by 4562
Abstract
Lasiodiplodia theobromae is one of the most aggressive agents of the grapevine trunk disease Botryosphaeria dieback. Through a dual RNA-sequencing approach, this study aimed to give a broader perspective on the infection strategy deployed by L. theobromae, while understanding grapevine response. Approximately [...] Read more.
Lasiodiplodia theobromae is one of the most aggressive agents of the grapevine trunk disease Botryosphaeria dieback. Through a dual RNA-sequencing approach, this study aimed to give a broader perspective on the infection strategy deployed by L. theobromae, while understanding grapevine response. Approximately 0.05% and 90% of the reads were mapped to the genomes of L. theobromae and Vitis vinifera, respectively. Over 2500 genes were significantly differentially expressed in infected plants after 10 dpi, many of which are involved in the inducible defense mechanisms of grapevines. Gene expression analysis showed changes in the fungal metabolism of phenolic compounds, carbohydrate metabolism, transmembrane transport, and toxin synthesis. These functions are related to the pathogenicity mechanisms involved in plant cell wall degradation and fungal defense against antimicrobial substances produced by the host. Genes encoding for the degradation of plant phenylpropanoid precursors were up-regulated, suggesting that the fungus could evade the host defense response using the phenylpropanoid pathway. The up-regulation of many distinct components of the phenylpropanoid pathway in plants supports this hypothesis. Moreover, genes related to phytoalexin biosynthesis, hormone metabolism, cell wall modification enzymes, and pathogenesis-related proteins seem to be involved in the host responses observed. This study provides additional insights into the molecular mechanisms of L. theobromae and V. vinifera interactions. Full article
(This article belongs to the Special Issue Host–Pathogen Interaction)
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11 pages, 5172 KiB  
Article
Structure of Staphylococcal Enterotoxin N: Implications for Binding Properties to Its Cellular Proteins
by Chi Zeng, Zhaoxin Liu and Zhenggang Han
Int. J. Mol. Sci. 2019, 20(23), 5921; https://doi.org/10.3390/ijms20235921 - 25 Nov 2019
Cited by 4 | Viewed by 2589
Abstract
Staphylococcus aureus strains produce a unique family of immunostimulatory exotoxins termed as bacterial superantigens (SAgs), which cross-link major histocompatibility complex class II (MHC II) molecule and T-cell receptor (TCR) to stimulate large numbers of T cells at extremely low concentrations. SAgs are associated [...] Read more.
Staphylococcus aureus strains produce a unique family of immunostimulatory exotoxins termed as bacterial superantigens (SAgs), which cross-link major histocompatibility complex class II (MHC II) molecule and T-cell receptor (TCR) to stimulate large numbers of T cells at extremely low concentrations. SAgs are associated with food poisoning and toxic shock syndrome. To date, 26 genetically distinct staphylococcal SAgs have been reported. This study reports the first X-ray structure of newly characterized staphylococcal enterotoxin N (SEN). SEN possesses the classical two domain architecture that includes an N-terminal oligonucleotide-binding fold and a C-terminal β-grasp domain. Amino acid and structure alignments revealed that several critical amino acids that are proposed to be responsible for MHC II and TCR molecule engagements are variable in SEN, suggesting that SEN may adopt a different binding mode to its cellular receptors. This work helps better understand the mechanisms of action of SAgs. Full article
(This article belongs to the Special Issue Host–Pathogen Interaction)
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21 pages, 2539 KiB  
Article
Identification of the Virulence Factors of Candidatus Liberibacter asiaticus via Heterologous Expression in Nicotiana benthamiana using Tobacco Mosaic Virus
by Xiaobao Ying, Mengyuan Wan, Linshuang Hu, Jinghua Zhang, Hui Li and Dianqiu Lv
Int. J. Mol. Sci. 2019, 20(22), 5575; https://doi.org/10.3390/ijms20225575 - 08 Nov 2019
Cited by 18 | Viewed by 3888
Abstract
Huanglongbing (HLB), also known as citrus greening, is the most destructive disease of citrus worldwide. HLB is associated with the non-culturable bacterium, Candidatus Liberibacter asiaticus (CaLas) in the United States. The virulence mechanism of CaLas is largely unknown, partly because [...] Read more.
Huanglongbing (HLB), also known as citrus greening, is the most destructive disease of citrus worldwide. HLB is associated with the non-culturable bacterium, Candidatus Liberibacter asiaticus (CaLas) in the United States. The virulence mechanism of CaLas is largely unknown, partly because of the lack of a mutant library. In this study, Tobacco mosaic virus (TMV) and Nicotiana benthamiana (N. benthamiana) were used for large-scale screening of the virulence factors of CaLas. Agroinfiltration of 60 putative virulence factors in N. benthamiana led to the identification of four candidates that caused severe symptoms in N. benthamiana, such as growth inhibition and cell death. CLIBASIA_05150 and CLIBASIA_04065C (C-terminal of CLIBASIA_04065) could cause cell death in the infiltrated leaves at five days post infiltration. Two low-molecular-weight candidates, CLIBASIA_00470 and CLIBASIA_04025, could inhibit plant growth. By converting start codon to stop codon or frameshifting, the four genes lost their harmful effects to N. benthamiana. It indicated that the four virulence factors functioned at the protein level rather than at the RNA level. The subcellular localization of the four candidates was determined by confocal laser scanning microscope. CLIBASIA_05150 located in the Golgi apparatus; CLIBASIA_04065 located in the mitochondrion; CLIBASIA_00470 and CLIBASIA_04025 distributed in cells as free GFP. The host proteins interacting with the four virulence factors were identified by yeast two-hybrid. The host proteins interacting with CLIBASIA_00470 and CLIBASIA_04025 were overlapping. Based on the phenotypes, the subcellular localization and the host proteins identified by yeast two-hybrid, CLIBASIA_00470 and CLIBASIA_04025, functioned redundantly. The hypothesis of CaLas virulence was proposed. CaLas affects citrus development and suppresses citrus disease resistance, comprehensively, in a complicated manner. Ubiquitin-mediated protein degradation might play a vital role in CaLas virulence. Deep characterization of the interactions between the identified virulence factors and their prey will shed light on HLB. Eventually, it will help in developing HLB-resistant citrus and save the endangered citrus industry worldwide. Full article
(This article belongs to the Special Issue Host–Pathogen Interaction)
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16 pages, 3951 KiB  
Article
Identification and Characterization of a Fatty Acid- and Retinoid-Binding Protein Gene (Ar-far-1) from the Chrysanthemum Foliar Nematode, Aphelenchoides ritzemabosi
by Shan-Wen Ding, Dong-Wei Wang, Yu Xiang, Chun-Ling Xu and Hui Xie
Int. J. Mol. Sci. 2019, 20(22), 5566; https://doi.org/10.3390/ijms20225566 - 07 Nov 2019
Cited by 4 | Viewed by 2528
Abstract
The chrysanthemum foliar nematode (CFN), Aphelenchoides ritzemabosi, is a migratory, plant-parasitic nematode that is widely distributed and infects the aboveground parts of many plants. The fatty acid- and retinoid-binding proteins (FAR) are nematode-specific proteins that are involved in the development, reproduction, and [...] Read more.
The chrysanthemum foliar nematode (CFN), Aphelenchoides ritzemabosi, is a migratory, plant-parasitic nematode that is widely distributed and infects the aboveground parts of many plants. The fatty acid- and retinoid-binding proteins (FAR) are nematode-specific proteins that are involved in the development, reproduction, and infection of nematodes and are secreted into the tissues to disrupt the plant defense reaction. In this study, we obtained the full-length sequence of the FAR gene (Ar-far-1) from CFN, which is 727 bp and includes a 546 bp ORF that encodes 181 amino acids. Ar-FAR-1 from CFN has the highest sequence similarity to Ab-FAR-1 from A. besseyi, and they are located within the same branch of the phylogenetic tree. Fluorescence-based ligand-binding analysis confirmed that recombinant Ar-FAR-1 was bound to fatty acids and retinol. Ar-far-1 mRNA was expressed in the muscle layer, intestine, female genital system, and egg of CFN, and more highly expressed in females than in males among the four developmental stages of CFN. We demonstrated that the reproduction number and infection capacity of CFN decreased significantly when Ar-far-1 was effectively silenced by in vitro RNAi. Ar-far-1 plays an important role in the development, reproduction, infectivity, and pathogenesis of CFN and may be used as an effective target gene for the control of CFN. The results provide meaningful data about the parasitic and pathogenic genes of CFN to study the interaction mechanism between plant-parasitic nematodes and hosts. Full article
(This article belongs to the Special Issue Host–Pathogen Interaction)
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14 pages, 2458 KiB  
Article
Study on the Role of Cytc in Response to BmNPV Infection in Silkworm, Bombyx mori (Lepidoptera)
by Xue-Yang Wang, Kang-Hui Wu, Hui-Lin Pang, Ping-Zhen Xu, Mu-Wang Li and Guo-Zheng Zhang
Int. J. Mol. Sci. 2019, 20(18), 4325; https://doi.org/10.3390/ijms20184325 - 04 Sep 2019
Cited by 22 | Viewed by 2800
Abstract
Bombyx mori nucleopolyhedrovirus (BmNPV) is one of the primary pathogens of the silkworm. Cytochrome c (cytc) showed a significant response to BmNPV infection in our previous transcriptome study. However, little is known about the role of Bombyx mori cytc (Bmcytc) in [...] Read more.
Bombyx mori nucleopolyhedrovirus (BmNPV) is one of the primary pathogens of the silkworm. Cytochrome c (cytc) showed a significant response to BmNPV infection in our previous transcriptome study. However, little is known about the role of Bombyx mori cytc (Bmcytc) in resistance to BmNPV infection. In this study, the expression levels analysis of Bmcytc showed stable expression levels in selected tissues of the resistant strain AN following BmNPV infection, while there was downregulation in the susceptible strain p50, except in the malpighian tubule. To further study the role of Bmcytc in viral infection, Bmcytc was knocked down with siRNA in vitro, resulting in significant downregulation of selected downstream genes of the mitochondrial pathway, including Bmapaf, Bmcaspase-Nc, and Bmcaspase-1; this was also confirmed by overexpression of Bmcytc using the pIZT/V5-His-mCherry insect vector, except Bmcaspase-1. Moreover, knockdown of Bmcytc significantly promoted the infection process of BmNPV in vitro, while the infection was inhibited by overexpression of Bmcytc at the early stage and subsequently increased rapidly. Based on these results, we concluded that Bmcytc plays a vital role in BmNPV infection by regulating the mitochondrial apoptosis pathway. Our work provides valuable data for the clarification of the mechanism of silkworm resistance to BmNPV infection. Full article
(This article belongs to the Special Issue Host–Pathogen Interaction)
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14 pages, 4542 KiB  
Article
Induction of Necrosis in Human Macrophage Cell Lines by Corynebacterium diphtheriae and Corynebacterium ulcerans Strains Isolated from Fatal Cases of Systemic Infections
by Dulanthi Weerasekera, Jonas Hahn, Martin Herrmann and Andreas Burkovski
Int. J. Mol. Sci. 2019, 20(17), 4109; https://doi.org/10.3390/ijms20174109 - 22 Aug 2019
Cited by 6 | Viewed by 3179
Abstract
When infecting a human host, Corynebacterium diphtheriae and Corynebacterium ulcerans are able to impair macrophage maturation and induce cell death. However, the underlying molecular mechanisms are not well understood. As a framework for this project, a combination of fluorescence microscopy, cytotoxicity assays, live [...] Read more.
When infecting a human host, Corynebacterium diphtheriae and Corynebacterium ulcerans are able to impair macrophage maturation and induce cell death. However, the underlying molecular mechanisms are not well understood. As a framework for this project, a combination of fluorescence microscopy, cytotoxicity assays, live cell imaging, and fluorescence-activated cell sorting was applied to understand the pathogenicity of two Corynebacterium strains isolated from fatal cases of systemic infections. The results showed a clear cytotoxic effect of the bacteria. The observed survival of the pathogens in macrophages and, subsequent, necrotic lysis of cells may be mechanisms explaining dissemination of C. diphtheriae and C. ulcerans to distant organs in the body. Full article
(This article belongs to the Special Issue Host–Pathogen Interaction)
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12 pages, 3704 KiB  
Article
VceC Mediated IRE1 Pathway and Inhibited CHOP-induced Apoptosis to Support Brucella Replication in Goat Trophoblast Cells
by Feijie Zhi, Dong Zhou, Furong Bai, Junmei Li, Caixia Xiang, Guangdong Zhang, Yaping Jin and Aihua Wang
Int. J. Mol. Sci. 2019, 20(17), 4104; https://doi.org/10.3390/ijms20174104 - 22 Aug 2019
Cited by 11 | Viewed by 3158
Abstract
The effectors of the type IV secretion system (T4SS) of bacteria play important roles in mediating bacterial intracellular proliferation and manipulating host-related pathway responses to bacterial infection. Brucella Spp. inhibit the apoptosis of host cells to benefit their own intracellular proliferation. However, the [...] Read more.
The effectors of the type IV secretion system (T4SS) of bacteria play important roles in mediating bacterial intracellular proliferation and manipulating host-related pathway responses to bacterial infection. Brucella Spp. inhibit the apoptosis of host cells to benefit their own intracellular proliferation. However, the underlying mechanisms between T4SS effectors and Brucella-inhibited apoptosis in goat trophoblast cells remain unclear. Here, based on Brucella suis vaccine strain 2, the VceC was deleted by allelic exchange. We show that ΔVceC was able to infect and proliferate to high titers in goat trophoblast cells (GTCs) and increase C/EBP-homologous protein (CHOP)-mediated apoptosis. GRP78 expression decreased upon ΔVceC infection. In addition, we discovered that the inositolrequiring enzyme 1 (IRE1) pathway was inhibited in this process. Changing endoplasmic reticulum (ER) stress affected Brucella intracellular replication in GTCs. The replication of ΔVceC was more sensitive under the different ERstress conditions in the GTC line after treatment with ER stress inhibitors 4 phenyl butyric acid (4-PBA) or ER stress activator Tm. Together, our findings show that VceC has a protective effect on the intracellular persistence of Brucella infection, and inhibits ER stress-induced apoptosis in the CHOP pathway. The present work provides new insights for understanding the mechanism of VceC in the establishment of chronic Brucella infection. Full article
(This article belongs to the Special Issue Host–Pathogen Interaction)
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15 pages, 2367 KiB  
Article
Conservation of Small Regulatory RNAs in Vibrio parahaemolyticus: Possible role of RNA-OUT Encoded by the Pathogenicity Island (VPaI-7) of Pandemic Strains
by Nicolás Plaza, Diliana Pérez-Reytor, Sebastián Ramírez-Araya, Alequis Pavón, Gino Corsini, David E. Loyola, Víctor Jaña, Leonardo Pavéz, Paola Navarrete, Roberto Bastías, Daniel Castillo and Katherine García
Int. J. Mol. Sci. 2019, 20(11), 2827; https://doi.org/10.3390/ijms20112827 - 10 Jun 2019
Cited by 4 | Viewed by 3069
Abstract
Small regulatory RNAs (sRNAs) are molecules that play an important role in the regulation of gene expression. sRNAs in bacteria can affect important processes, such as metabolism and virulence. Previous studies showed a significant role of sRNAs in the Vibrio species, but knowledge [...] Read more.
Small regulatory RNAs (sRNAs) are molecules that play an important role in the regulation of gene expression. sRNAs in bacteria can affect important processes, such as metabolism and virulence. Previous studies showed a significant role of sRNAs in the Vibrio species, but knowledge about Vibrio parahaemolyticus is limited. Here, we examined the conservation of sRNAs between V. parahaemolyticus and other human Vibrio species, in addition to investigating the conservation between V. parahaemolyticus strains differing in pandemic origin. Our results showed that only 7% of sRNAs were conserved between V. parahaemolyticus and other species, but 88% of sRNAs were highly conserved within species. Nonetheless, two sRNAs coding to RNA-OUT, a component of the Tn10/IS10 system, were exclusively present in pandemic strains. Subsequent analysis showed that both RNA-OUT were located in pathogenicity island-7 and would interact with transposase VPA1379, according to the model of pairing of IS10-encoded antisense RNAs. According to the location of RNA-OUT/VPA1379, we also investigated if they were expressed during infection. We observed that the transcriptional level of VPA1379 was significantly increased, while RNA-OUT was decreased at three hours post-infection. We suggest that IS10 transcription increases in pandemic strains during infection, probably to favor IS10 transposition and improve their fitness when they are facing adverse conditions. Full article
(This article belongs to the Special Issue Host–Pathogen Interaction)
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