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Ma XQ, Wang B, Wei W, Tan FC, Su H, Zhang JZ, Zhao CY, Zheng HJ, Feng YQ, Shen W, Yang JB, Li FL. Alginate oligosaccharide assimilation by gut microorganisms and the potential role in gut inflammation alleviation. Appl Environ Microbiol 2024; 90:e0004624. [PMID: 38563787 PMCID: PMC11107165 DOI: 10.1128/aem.00046-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 03/10/2024] [Indexed: 04/04/2024] Open
Abstract
Dietary fiber metabolism by gut microorganisms plays important roles in host physiology and health. Alginate, the major dietary fiber of daily diet seaweeds, is drawing more attention because of multiple biological activities. To advance the understanding of alginate assimilation mechanism in the gut, we show the presence of unsaturated alginate oligosaccharides (uAOS)-specific alginate utilization loci (AUL) in human gut microbiome. As a representative example, a working model of the AUL from the gut microorganism Bacteroides clarus was reconstructed from biochemistry and transcriptome data. The fermentation of resulting monosaccharides through Entner-Doudoroff pathway tunes the metabolism of short-chain fatty acids and amino acids. Furthermore, we show that uAOS feeding protects the mice against dextran sulfate sodium-induced acute colitis probably by remodeling gut microbiota and metabolome. IMPORTANCE Alginate has been included in traditional Chinese medicine and daily diet for centuries. Recently discovered biological activities suggested that alginate-derived alginate oligosaccharides (AOS) might be an active ingredient in traditional Chinese medicine, but how these AOS are metabolized in the gut and how it affects health need more information. The study on the working mechanism of alginate utilization loci (AUL) by the gut microorganism uncovers the role of unsaturated alginate oligosaccharides (uAOS) assimilation in tuning short-chain fatty acids and amino acids metabolism and demonstrates that uAOS metabolism by gut microorganisms results in a variation of cell metabolites, which potentially contributes to the physiology and health of gut.
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Affiliation(s)
- Xiao-Qing Ma
- Qingdao C1 Refinery Engineering Research Center, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
| | - Bing Wang
- Qingdao C1 Refinery Engineering Research Center, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
| | - Wei Wei
- Innovation Center of Marine Drug Screening & Evaluation, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Fang-Cheng Tan
- Qingdao C1 Refinery Engineering Research Center, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
| | - Hang Su
- Qingdao C1 Refinery Engineering Research Center, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
| | - Jun-Zhe Zhang
- Qingdao C1 Refinery Engineering Research Center, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
| | - Chen-Yang Zhao
- Innovation Center of Marine Drug Screening & Evaluation, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Hua-Jun Zheng
- Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Yan-Qin Feng
- College of Life Sciences, Qingdao Agricultural University, Qingdao, China
| | - Wei Shen
- College of Life Sciences, Qingdao Agricultural University, Qingdao, China
| | - Jin-Bo Yang
- Innovation Center of Marine Drug Screening & Evaluation, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Fu-Li Li
- Qingdao C1 Refinery Engineering Research Center, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
- Shandong Energy Institute, Qingdao, China
- Qingdao New Energy Shandong Laboratory, Qingdao, China
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Sweet LA, Kuss-Duerkop SK, Byndloss MX, Keestra-Gounder AM. Nitrate-mediated luminal expansion of Salmonella Typhimurium is dependent on the ER stress protein CHOP. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.03.565559. [PMID: 37961401 PMCID: PMC10635149 DOI: 10.1101/2023.11.03.565559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Salmonella Typhimurium is an enteric pathogen that employs a variety of mechanisms to exploit inflammation resulting in expansion in the intestinal tract, but host factors that contribute to or counteract the luminal expansion are not well-defined. Endoplasmic reticulum (ER) stress induces inflammation and plays an important role in the pathogenesis of infectious diseases. However, little is known about the contribution of ER stress-induced inflammation during Salmonella pathogenesis. Here, we demonstrate that the ER stress markers Hspa5 and Xbp1 are induced in the colon of S. Typhimurium infected mice, but the pro-apoptotic transcription factor Ddit3, that encodes for the protein CHOP, is significantly downregulated. S. Typhimurium-infected mice deficient for CHOP displayed a significant decrease in inflammation, colonization, dissemination, and pathology compared to littermate control mice. Preceding the differences in S. Typhimurium colonization, a significant decrease in Nos2 gene and iNOS protein expression was observed. Deletion of Chop decreased the bioavailability of nitrate in the colon leading to reduced fitness advantage of wild type S. Typhimurium over a napA narZ narG mutant strain (deficient in nitrate respiration). CD11b+ myeloid cells, but not intestinal epithelial cells, produced iNOS resulting in nitrate bioavailability for S. Typhimurium to expand in the intestinal tract in a CHOP-dependent manner. Altogether our work demonstrates that the host protein CHOP facilitates iNOS expression in CD11b+ cells thereby contributing to luminal expansion of S. Typhimurium via nitrate respiration.
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Affiliation(s)
- Lydia A. Sweet
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Sharon K. Kuss-Duerkop
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Mariana X. Byndloss
- Howard Hughes Medical Institute, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Institute of Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Digestive Disease Center, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Microbiome Innovation Center, Vanderbilt University, Nashville, TN 37235, USA
| | - A. Marijke Keestra-Gounder
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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Siri M, Dastghaib S, Zamani M, Rahmani-Kukia N, Geraylow KR, Fakher S, Keshvarzi F, Mehrbod P, Ahmadi M, Mokarram P, Coombs KM, Ghavami S. Autophagy, Unfolded Protein Response, and Neuropilin-1 Cross-Talk in SARS-CoV-2 Infection: What Can Be Learned from Other Coronaviruses. Int J Mol Sci 2021; 22:5992. [PMID: 34206057 PMCID: PMC8199451 DOI: 10.3390/ijms22115992] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 05/28/2021] [Indexed: 02/07/2023] Open
Abstract
The COVID-19 pandemic is caused by the 2019-nCoV/SARS-CoV-2 virus. This severe acute respiratory syndrome is currently a global health emergency and needs much effort to generate an urgent practical treatment to reduce COVID-19 complications and mortality in humans. Viral infection activates various cellular responses in infected cells, including cellular stress responses such as unfolded protein response (UPR) and autophagy, following the inhibition of mTOR. Both UPR and autophagy mechanisms are involved in cellular and tissue homeostasis, apoptosis, innate immunity modulation, and clearance of pathogens such as viral particles. However, during an evolutionary arms race, viruses gain the ability to subvert autophagy and UPR for their benefit. SARS-CoV-2 can enter host cells through binding to cell surface receptors, including angiotensin-converting enzyme 2 (ACE2) and neuropilin-1 (NRP1). ACE2 blockage increases autophagy through mTOR inhibition, leading to gastrointestinal complications during SARS-CoV-2 virus infection. NRP1 is also regulated by the mTOR pathway. An increased NRP1 can enhance the susceptibility of immune system dendritic cells (DCs) to SARS-CoV-2 and induce cytokine storm, which is related to high COVID-19 mortality. Therefore, signaling pathways such as mTOR, UPR, and autophagy may be potential therapeutic targets for COVID-19. Hence, extensive investigations are required to confirm these potentials. Since there is currently no specific treatment for COVID-19 infection, we sought to review and discuss the important roles of autophagy, UPR, and mTOR mechanisms in the regulation of cellular responses to coronavirus infection to help identify new antiviral modalities against SARS-CoV-2 virus.
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Affiliation(s)
- Morvarid Siri
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (M.S.); (M.Z.)
| | - Sanaz Dastghaib
- Endocrinology and Metabolism Research Center, Shiraz University of Medical Sciences, Shiraz 7193635899, Iran;
| | - Mozhdeh Zamani
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (M.S.); (M.Z.)
| | - Nasim Rahmani-Kukia
- Department of Biochemistry, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (N.R.-K.); (S.F.); (F.K.)
| | | | - Shima Fakher
- Department of Biochemistry, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (N.R.-K.); (S.F.); (F.K.)
| | - Fatemeh Keshvarzi
- Department of Biochemistry, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (N.R.-K.); (S.F.); (F.K.)
| | - Parvaneh Mehrbod
- Influenza and Respiratory Viruses Department, Pasteur Institute of Iran, Tehran 1316943551, Iran;
| | - Mazaher Ahmadi
- Faculty of Chemistry, Bu-Ali Sina University, Hamedan 6517838695, Iran;
| | - Pooneh Mokarram
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (M.S.); (M.Z.)
- Department of Biochemistry, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (N.R.-K.); (S.F.); (F.K.)
| | - Kevin M. Coombs
- Department of Medical Microbiology and Infectious Diseases, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada;
| | - Saeid Ghavami
- Autophagy Research Center, Shiraz University of Medical Sciences, Shiraz 7134845794, Iran; (M.S.); (M.Z.)
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada
- Faculty of Medicine, Katowice School of Technology, 40-555 Katowice, Poland
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Zhang Z, Wang Y, Shan Y, Zhou R, Yin W. Oroxylin A alleviates immunoparalysis of CLP mice by degrading CHOP through interacting with FBXO15. Sci Rep 2020; 10:19272. [PMID: 33159144 PMCID: PMC7648083 DOI: 10.1038/s41598-020-76285-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 09/22/2020] [Indexed: 11/08/2022] Open
Abstract
Clinical reports have found that with the improvement of treatment, most septic patients are able to survive the severe systemic inflammatory response and to enter the immunoparalysis stage. Considering that immunoparalysis leads to numerous deaths of clinical sepsis patients, alleviation of the occurrence and development of immunoparalysis has become a top priority in the treatment of sepsis. In our study, we investigate the effects of oroxylin A on sepsis in cecal ligation and puncture (CLP) mice. We find that the 60 h + 84 h (30 mg/kg) injection scheme of oroxylin A induce the production of pro-inflammatory factors, and further significantly improves the survival of CLP mice during the middle or late stages of sepsis. Mechanistically, C/EBP-homologous protein (CHOP) is upregulated and plays anti-inflammatory roles to facilitate the development of immunoparalysis in CLP mice. Oroxylin A induces the transcription of E3 ligase F-box only protein 15 gene (fbxo15), and activated FBXO15 protein binds to CHOP and further mediates the degradation of CHOP through the proteasome pathway, which eventually relieves the immunoparalysis of CLP mice. Taken together, these findings suggest oroxylin A relieves the immunoparalysis of CLP mice by degrading CHOP through interacting with FBXO15.
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Affiliation(s)
- Zhaoxin Zhang
- The State Key Lab of Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, 210023, China
| | - Yun Wang
- The State Key Lab of Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, 210023, China
| | - Yating Shan
- The State Key Lab of Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, 210023, China
| | - Ri Zhou
- The State Key Lab of Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, 210023, China
| | - Wu Yin
- The State Key Lab of Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, 210023, China.
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Rao Z, Sun J, Pan X, Chen Z, Sun H, Zhang P, Gao M, Ding Z, Liu C. Hyperglycemia Aggravates Hepatic Ischemia and Reperfusion Injury by Inhibiting Liver-Resident Macrophage M2 Polarization via C/EBP Homologous Protein-Mediated Endoplasmic Reticulum Stress. Front Immunol 2017; 8:1299. [PMID: 29081777 PMCID: PMC5645540 DOI: 10.3389/fimmu.2017.01299] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 09/27/2017] [Indexed: 12/13/2022] Open
Abstract
Aggravated liver ischemia and reperfusion (IR) injury has been observed in hyperglycemic hosts, but its underlying mechanism remains undefined. Liver-resident macrophages (Kupffer cells, KCs) and endoplasmic reticulum (ER) stress play crucial roles in the pathogenesis of liver IR injury. In this study, we evaluated the role of ER stress in regulating KC activation and liver IR injury in a streptozotocin-induced hyperglycemic/diabetic mouse model. Compared to the control group (CON group), hyperglycemic mice exhibited a significant increase in liver injury and intrahepatic inflammation following IR. KCs obtained from hyperglycemic mice secreted higher levels of the pro-inflammatory factors TNF-α and IL-6, while they secreted significantly lower levels of the anti-inflammatory factor IL-10. Furthermore, enhanced ER stress was revealed by increased C/EBP homologous protein (CHOP) activation in both IR-stressed livers and KCs from hyperglycemic mice. Specific CHOP knockdown in KCs by siRNA resulted in a slight decrease in TNF-α and IL-6 secretion but dramatically enhanced anti-inflammatory IL-10 secretion in the hyperglycemic group, while no significant changes in cytokine production were observed in the CON group. We also analyzed the role of hyperglycemia in macrophage M1/M2 polarization. Interestingly, we found that hyperglycemia inhibited IL-10-secreting M2-like macrophage polarization, as revealed by decreased Arg1 and Mrc1 gene induction accompanied by a decrease in STAT3 and STAT6 signaling pathway activation. CHOP knockdown restored Arg1 and Mrc1 gene induction, STAT3 and STAT6 activation, and most importantly, IL-10 secretion in hyperglycemic KCs. Finally, in vivo CHOP knockdown in KCs enhanced intrahepatic anti-inflammatory IL-10 gene induction and protected the liver against IR injury in hyperglycemic mice but had no significant effects in control mice. Our results demonstrate that hyperglycemia induces hyper-inflammatory activation of KCs during liver IR injury. Thus, hyperglycemia-induced CHOP over-activation inhibits IL-10-secreting M2-like macrophage polarization by liver-resident macrophages, thereby leading to excessive inflammation and the exacerbation of liver IR injury in diabetic/hyperglycemic hosts. This study provides novel mechanistic insight into macrophage inflammatory activation under hyperglycemic conditions during liver IR.
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Affiliation(s)
- Zhuqing Rao
- Department of Anesthesiology, First Affiliated Hospital with Nanjing Medical University, Nanjing, China
| | - Jie Sun
- Department of Anesthesiology, First Affiliated Hospital with Nanjing Medical University, Nanjing, China
| | - Xiongxiong Pan
- Department of Anesthesiology, First Affiliated Hospital with Nanjing Medical University, Nanjing, China
| | - Ziyang Chen
- Department of Anesthesiology, First Affiliated Hospital with Nanjing Medical University, Nanjing, China
| | - Heliang Sun
- Department of Anesthesiology, First Affiliated Hospital with Nanjing Medical University, Nanjing, China
| | - Panpan Zhang
- Department of Anesthesiology, First Affiliated Hospital with Nanjing Medical University, Nanjing, China
| | - Mei Gao
- Department of Anesthesiology, First Affiliated Hospital with Nanjing Medical University, Nanjing, China
| | - Zhengnian Ding
- Department of Anesthesiology, First Affiliated Hospital with Nanjing Medical University, Nanjing, China
| | - Cunming Liu
- Department of Anesthesiology, First Affiliated Hospital with Nanjing Medical University, Nanjing, China
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6
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Doran AC, Ozcan L, Cai B, Zheng Z, Fredman G, Rymond CC, Dorweiler B, Sluimer JC, Hsieh J, Kuriakose G, Tall AR, Tabas I. CAMKIIγ suppresses an efferocytosis pathway in macrophages and promotes atherosclerotic plaque necrosis. J Clin Invest 2017; 127:4075-4089. [PMID: 28972541 DOI: 10.1172/jci94735] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 08/10/2017] [Indexed: 01/29/2023] Open
Abstract
Atherosclerosis is the underlying etiology of cardiovascular disease, the leading cause of death worldwide. Atherosclerosis is a heterogeneous disease in which only a small fraction of lesions lead to heart attack, stroke, or sudden cardiac death. A distinct type of plaque containing large necrotic cores with thin fibrous caps often precipitates these acute events. Here, we show that Ca2+/calmodulin-dependent protein kinase γ (CaMKIIγ) in macrophages plays a major role in the development of necrotic, thin-capped plaques. Macrophages in necrotic and symptomatic atherosclerotic plaques in humans as well as advanced atherosclerotic lesions in mice demonstrated activation of CaMKII. Western diet-fed LDL receptor-deficient (Ldlr-/-) mice with myeloid-specific deletion of CaMKII had smaller necrotic cores with concomitantly thicker collagen caps. These lesions demonstrated evidence of enhanced efferocytosis, which was associated with increased expression of the macrophage efferocytosis receptor MerTK. Mechanistic studies revealed that CaMKIIγ-deficient macrophages and atherosclerotic lesions lacking myeloid CaMKIIγ had increased expression of the transcription factor ATF6. We determined that ATF6 induces liver X receptor-α (LXRα), an Mertk-inducing transcription factor, and that increased MerTK expression and efferocytosis in CaMKIIγ-deficient macrophages is dependent on LXRα. These findings identify a macrophage CaMKIIγ/ATF6/LXRα/MerTK pathway as a key factor in the development of necrotic atherosclerotic plaques.
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Affiliation(s)
- Amanda C Doran
- Department of Medicine, Columbia University, New York, New York, USA
| | - Lale Ozcan
- Department of Medicine, Columbia University, New York, New York, USA
| | - Bishuang Cai
- Department of Medicine, Columbia University, New York, New York, USA
| | - Ze Zheng
- Department of Medicine, Columbia University, New York, New York, USA
| | - Gabrielle Fredman
- Department of Molecular and Cellular Physiology, Center for Cardiovascular Sciences, Albany Medical Center, Albany, New York, USA
| | | | - Bernhard Dorweiler
- Department of Cardiothoracic and Vascular Surgery, Universitätsmedizin Mainz, Johannes-Gutenberg University, Mainz, Germany
| | - Judith C Sluimer
- Department of Pathology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Joanne Hsieh
- Department of Medicine, Columbia University, New York, New York, USA
| | | | - Alan R Tall
- Department of Medicine, Columbia University, New York, New York, USA
| | - Ira Tabas
- Department of Medicine, Columbia University, New York, New York, USA.,Department of Physiology and Cellular Biophysics and.,Department of Pathology and Cell Biology, Columbia University, New York, New York, USA
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7
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Tsalikis J, Pan Q, Tattoli I, Maisonneuve C, Blencowe BJ, Philpott DJ, Girardin SE. The transcriptional and splicing landscape of intestinal organoids undergoing nutrient starvation or endoplasmic reticulum stress. BMC Genomics 2016; 17:680. [PMID: 27561422 PMCID: PMC5000506 DOI: 10.1186/s12864-016-2999-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 08/05/2016] [Indexed: 01/08/2023] Open
Abstract
Background The intestinal epithelium plays a critical role in nutrient absorption and innate immune defense. Recent studies showed that metabolic stress pathways, in particular the integrated stress response (ISR), control intestinal epithelial cell fate and function. Here, we used RNA-seq to analyze the global transcript level and alternative splicing responses of primary murine enteroids undergoing two distinct ISR-triggering stresses, endoplasmic reticulum (ER) stress and nutrient starvation. Results Our results reveal the core transcript level response to ISR-associated stress in murine enteroids, which includes induction of stress transcription factors, as well as genes associated with chemotaxis and inflammation. We also identified the transcript expression signatures that are unique to each ISR stress. Among these, we observed that ER stress and nutrient starvation had opposite effects on intestinal stem cell (ISC) transcriptional reprogramming. In agreement, ER stress decreased EdU incorporation, a marker of cell proliferation, in primary murine enteroids, while nutrient starvation had an opposite effect. We also analyzed the impact of these cellular stresses on mRNA splicing regulation. Splicing events commonly regulated by both stresses affected genes regulating splicing and were associated with nonsense-mediated decay (NMD), suggesting that splicing is modulated by an auto-regulatory feedback loop during stress. In addition, we also identified a number of genes displaying stress-specific splicing regulation. We suggest that functional gene expression diversity may arise during stress by the coordination of alternative splicing and alternative translation, and that this diversity might contribute to the cellular response to stress. Conclusions Together, these results provide novel understanding of the importance of metabolic stress pathways in the intestinal epithelium. Specifically, the importance of cellular stresses in the regulation of immune and defense function, metabolism, proliferation and ISC activity in the intestinal epithelium is highlighted. Furthermore, this work highlights an under-appreciated role played by alternative splicing in shaping the response to stress and reveals a potential mechanism for gene regulation involving coupling of AS and alternative translation start sites. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2999-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jessica Tsalikis
- Department of Laboratory Medicine and Pathobiology, Toronto, Canada
| | - Qun Pan
- Department of Molecular Genetics, Donnelly Centre, Toronto, Canada
| | - Ivan Tattoli
- Department of Laboratory Medicine and Pathobiology, Toronto, Canada.,Department of Immunology, University of Toronto, Toronto, Canada
| | | | | | - Dana J Philpott
- Department of Immunology, University of Toronto, Toronto, Canada
| | - Stephen E Girardin
- Department of Laboratory Medicine and Pathobiology, Toronto, Canada. .,Department of Immunology, University of Toronto, Toronto, Canada.
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