title: Tissue-Specific Immune Gene Expression in the Migratory Locust, Locusta Migratoria.
abstract: The ability of hosts to respond to infection involves several complex immune recognition pathways. Broadly conserved pathogen-associated molecular patterns (PAMPs) allow individuals to target a range of invading microbes. Recently, studies on insect innate immunity have found evidence that a single pathogen can activate different immune pathways across species. In this study, expression changes in immune genes encoding peptidoglycan-recognition protein SA (PGRP-SA), gram-negative binding protein 1 (GNBP1) and prophenoloxidase (ProPO) were investigated in Locusta migratoria, following an immune challenge using injected lipopolysaccharide (LPS) solution from Escherichia coli. Since immune activation might also be tissue-specific, gene expression levels were followed across a range of tissue types. For PGRP-SA, expression increased in response to LPS within all seven of the tissue-types assayed and differed significantly between tissues. Expression of GNBP1 similarly varied across tissue types, yet showed no clear expression difference between LPS-injected and uninfected locusts. Increases in ProPO expression in response to LPS, however, could only be detected in the gut sections. This study has revealed tissue-specific immune response to add a new level of complexity to insect immune studies. In addition to variation in recognition pathways identified in previous works, tissue-specificity should be carefully considered in similar works.
authors.affiliation: School of Biological Sciences, The University of Sydney, NSW 2006, Australia. tamara.pulpitel@sydney.edu.au.
authors.forename: Tamara
authors.initials: T
authors.lastname: Pulpitel
authors.affiliation: Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, New South Wales 2007, Australia. mathieu.pernice@uts.edu.au.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Pernice
authors.affiliation: School of Biological Sciences, The University of Sydney, NSW 2006, Australia. stephen.simpson@sydney.edu.au.|The Charles Perkins Centre, The University of Sydney, NSW 2006, Australia. stephen.simpson@sydney.edu.au.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Simpson
authors.affiliation: School of Biological Sciences, The University of Sydney, NSW 2006, Australia. fleur.ponton@sydney.edu.au.|The Charles Perkins Centre, The University of Sydney, NSW 2006, Australia. fleur.ponton@sydney.edu.au.
authors.forename: Fleur
authors.initials: F
authors.lastname: Ponton
keywords: gene expression; insect immunity; locust; tissue-specificity