title: IRF7 in the Australian black flying fox, Pteropus alecto: evidence for a unique expression pattern and functional conservation.
abstract: As the only flying mammal, bats harbor a number of emerging and re-emerging viruses, many of which cause severe diseases in humans and other mammals yet result in no clinical symptoms in bats. As the master regulator of the interferon (IFN)-dependent immune response, IFN regulatory factor 7 (IRF7) plays a central role in innate antiviral immunity. To explore the role of bat IRF7 in the regulation of the IFN response, we performed sequence and functional analysis of IRF7 from the pteropid bat, Pteropus alecto. Our results demonstrate that bat IRF7 retains the ability to bind to MyD88 and activate the IFN response despite unique changes in the MyD88 binding domain. We also demonstrate that bat IRF7 has a unique expression pattern across both immune and non-immune related tissues and is inducible by double-strand RNA. The broad tissue distribution of IRF7 may provide bats with an enhanced ability to rapidly activate the IFN response in a wider range of tissues compared to other mammals. The importance of IRF7 in antiviral activity against the bat reovirus, Pulau virus was confirmed by siRNA knockdown of IRF7 in bat cells resulting in enhanced viral replication. Our results highlight the importance of IRF7 in innate antiviral immunity in bats.
authors.affiliation: CSIRO, Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhou
authors.affiliation: CSIRO, Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Chris
authors.initials: C
authors.lastname: Cowled
authors.affiliation: Centre for Innate Immunity and Infectious Diseases, Monash Institute of Medical Research-Prince Henry Institute of Medical Research, Monash University, Clayton, Victoria, Australia.
authors.forename: Ashley
authors.initials: A
authors.lastname: Mansell
authors.affiliation: CSIRO, Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: Monaghan
authors.affiliation: CSIRO, Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Diane
authors.initials: D
authors.lastname: Green
authors.affiliation: Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.
authors.forename: Lijun
authors.initials: L
authors.lastname: Wu
authors.affiliation: Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China.
authors.forename: Zhengli
authors.initials: Z
authors.lastname: Shi
authors.affiliation: CSIRO, Australian Animal Health Laboratory, Geelong, Victoria, Australia; Program in Emerging Infectious Diseases, Duke-National University of Singapore Graduate Medical School, Singapore.
authors.forename: Lin-Fa
authors.initials: LF
authors.lastname: Wang
authors.affiliation: CSIRO, Australian Animal Health Laboratory, Geelong, Victoria, Australia.
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Baker
mesh_terms: D000818:Animals; D001483:Base Sequence; D002685:Chiroptera / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000502:physiology*; D007113:Immunity, Innate / Q000502:physiology; D050839:Interferon Regulatory Factor-7 / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D008969:Molecular Sequence Data; D053594:Myeloid Differentiation Factor 88 / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D009928:Organ Specificity / Q000502:physiology
chemical_list: D050839:Interferon Regulatory Factor-7; D053594:Myeloid Differentiation Factor 88
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