title: The integrated endoplasmic reticulum stress response in Leishmania amazonensis macrophage infection: the role of X-box binding protein 1 transcription factor.
abstract: Endoplasmic reticulum (ER) stress triggers the integrated ER-stress response (IERSR) that ensures cellular survival of ER stress and represents a primordial form of innate immunity. We investigated the role of IERSR duringLeishmania amazonensisinfection. Treatment of RAW 264.7 infected macrophages with the ER stress-inducing agent thapsigargin (TG; 1 μM) increasedL. amazonensisinfectivity in an IFN1-α receptor (IFNAR)-dependent manner. In Western blot assays, we showed thatL. amazonensisactivates the inositol-requiring enzyme (IRE1)/ X-box binding protein (XBP)-1-splicing arms of the IERSR in host cells. In chromatin immunoprecipitation (ChIP) assays, we showed an increased occupancy of enhancer and promoter sequences for theIfnbgene by XBP1 in infected RAW 264.7 cells. Knocking down XBP1 expression by transducing RAW 264.7 cells with the short hairpin XBP1 lentiviral vector significantly reduced the parasite proliferation associated with impaired translocation of phosphorylated IFN regulatory transcription factor (IRF)-3 to the nucleus and a decrease in IFN1-β expression. Knocking down XBP1 expression also increased NO concentration, as determined by Griess reaction and reduced the expression of antioxidant genes, such as heme oxygenase (HO)-1, that protect parasites from oxidative stress. We conclude thatL. amazonensisactivation of XBP1 plays a critical role in infection by protecting the parasites from oxidative stress and increasing IFN1-β expression.-Dias-Teixeira, K. L., Calegari-Silva, T. C., Dos Santos, G. R. R. M., Vitorino dos Santos, J., Lima, C., Medina, J. M., Aktas, B. H., Lopes, U. G. The integrated endoplasmic reticulum stress response inLeishmania amazonensismacrophage infection: the role of X-box binding protein 1 transcription factor.
authors.affiliation: *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Karina Luiza
authors.initials: KL
authors.lastname: Dias-Teixeira
authors.affiliation: *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Teresa Cristina
authors.initials: TC
authors.lastname: Calegari-Silva
authors.affiliation: *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Guilherme R R M
authors.initials: GR
authors.lastname: dos Santos
authors.affiliation: *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: José
authors.initials: J
authors.lastname: Vitorino Dos Santos
authors.affiliation: *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Carolina
authors.initials: C
authors.lastname: Lima
authors.affiliation: *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Jorge Mansur
authors.initials: JM
authors.lastname: Medina
authors.affiliation: *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Bertal Huseyin
authors.initials: BH
authors.lastname: Aktas
authors.affiliation: *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA lopesu@biof.ufrj.br.
authors.forename: Ulisses G
authors.initials: UG
authors.lastname: Lopes
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D059865:Endoplasmic Reticulum Stress; D015870:Gene Expression; D057809:HEK293 Cells; D051547:Heme Oxygenase-1 / Q000235:genetics / Q000378:metabolism; D006790:Host-Parasite Interactions; D006801:Humans; D016899:Interferon-beta / Q000235:genetics / Q000378:metabolism; D007891:Leishmania / Q000502:physiology*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism* / Q000382:microbiology*; D051379:Mice; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D034622:RNA Interference; D017382:Reactive Oxygen Species / Q000378:metabolism; D000071701:Regulatory Factor X Transcription Factors; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019284:Thapsigargin / Q000494:pharmacology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D000071717:X-Box Binding Protein 1
chemical_list: D004268:DNA-Binding Proteins; D017382:Reactive Oxygen Species; D000071701:Regulatory Factor X Transcription Factors; D014157:Transcription Factors; D000071717:X-Box Binding Protein 1; C000605543:XBP1 protein, human; C000605544:Xbp1 protein, mouse; D019284:Thapsigargin; D016899:Interferon-beta; D051547:Heme Oxygenase-1
keywords: ER stress; IFN1-β; XBP1; oxidative stress; thapsigargin IRE1