title: Gene expression changes in the salivary glands of Anopheles coluzzii elicited by Plasmodium berghei infection.
abstract: BACKGROUND
  Malaria is a devastating infectious disease caused by Plasmodium parasites transmitted through the bites of infected Anopheles mosquitoes. Salivary glands are the only mosquito tissue invaded by Plasmodium sporozoites, being a key stage for the effective parasite transmission, making the study of Anopheles sialome highly relevant.
  
  
  METHODS
  RNA-sequencing was used to compare differential gene expression in salivary glands of uninfected and Plasmodium berghei-infected Anopheles coluzzii mosquitoes. RNA-seq results were validated by quantitative RT-PCR. The transmembrane glucose transporter gene AGAP007752 was selected for functional analysis by RNA interference. The effect of gene silencing on infection level was evaluated. The putative function and tertiary structure of the protein was assessed.
  
  
  RESULTS
  RNA-seq data showed that 2588 genes were differentially expressed in mosquitoes salivary glands in response to P. berghei infection, being 1578 upregulated and 1010 downregulated. Metabolism, Immunity, Replication/Transcription/Translation, Proteolysis and Transport were the mosquito gene functional classes more affected by parasite infection. Endopeptidase coding genes were the most abundant within the differentially expressed genes in infected salivary glands (P < 0.001). Based on its putative function and expression level, the transmembrane glucose transporter gene, AGAP007752, was selected for functional analysis by RNA interference. The results demonstrated that the number of sporozoites was 44.3% lower in mosquitoes fed on infected mice after AGAPP007752 gene knockdown when compared to control (P < 0.01).
  
  
  CONCLUSIONS
  Our hypothesis is that the protein encoded by the gene AGAPP007752 may play a role on An. coluzzii salivary glands infection by Plasmodium parasite, working as a sporozoite receptor and/or promoting a favorable environment for the capacity of sporozoites.
authors.affiliation: Instituto de Higiene e Medicina Tropical (IHMT), Lisbon, Portugal. renato.silva@ihmt.unl.pt.
authors.forename: Renato
authors.initials: R
authors.lastname: Pinheiro-Silva
authors.affiliation: Instituto de Higiene e Medicina Tropical (IHMT), Lisbon, Portugal. lara.borges@ihmt.unl.pt.|Global Health and Tropical Medicine (GHMT), Instituto de Higiene e Medicina Tropical (IHMT), Lisbon, Portugal. lara.borges@ihmt.unl.pt.
authors.forename: Lara
authors.initials: L
authors.lastname: Borges
authors.affiliation: Unidade de Biofísica e Expressão Genética, Instituto de Medicina Molecular (IMM), Lisbon, Portugal. luis@luispedro.org.
authors.forename: Luís Pedro
authors.initials: LP
authors.lastname: Coelho
authors.affiliation: Center for Infection and Immunity of Lille (CIIL), Institut Pasteur de Lille, Lille, France. cabezasalejandrocruz@gmail.com.|SaBio. Instituto de Investigación de Recursos Cinegéticos, IREC-CSIC-UCLM-JCCM, Ciudad Real, Spain. cabezasalejandrocruz@gmail.com.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Cabezas-Cruz
authors.affiliation: Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, Czech Republic. valdjj@gmail.com.
authors.forename: James J
authors.initials: JJ
authors.lastname: Valdés
authors.affiliation: Instituto de Higiene e Medicina Tropical (IHMT), Lisbon, Portugal. virgilio.do.rosario@gmail.com.
authors.forename: Virgílio
authors.initials: V
authors.lastname: do Rosário
authors.affiliation: SaBio. Instituto de Investigación de Recursos Cinegéticos, IREC-CSIC-UCLM-JCCM, Ciudad Real, Spain. jose_delafuente@yahoo.com.|Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, USA. jose_delafuente@yahoo.com.
authors.forename: José
authors.initials: J
authors.lastname: de la Fuente
authors.affiliation: Instituto de Higiene e Medicina Tropical (IHMT), Lisbon, Portugal. adomingos@ihmt.unl.pt.|Global Health and Tropical Medicine (GHMT), Instituto de Higiene e Medicina Tropical (IHMT), Lisbon, Portugal. adomingos@ihmt.unl.pt.
authors.forename: Ana
authors.initials: A
authors.lastname: Domingos
mesh_terms: D000818:Animals; D000852:Anopheles / Q000502:physiology*; D020869:Gene Expression Profiling; D020868:Gene Silencing; D051246:Glucose Transport Proteins, Facilitative / Q000037:antagonists & inhibitors*; D054884:Host-Pathogen Interactions; D051379:Mice; D010962:Plasmodium berghei / Q000254:growth & development*; D060888:Real-Time Polymerase Chain Reaction; D011956:Receptors, Cell Surface / Q000037:antagonists & inhibitors; D012469:Salivary Glands / Q000469:parasitology; D017423:Sequence Analysis, RNA
chemical_list: D051246:Glucose Transport Proteins, Facilitative; D011956:Receptors, Cell Surface