title: Class II ADP-ribosylation factors are required for efficient secretion of dengue viruses.
abstract: Identification and characterization of virus-host interactions are very important steps toward a better understanding of the molecular mechanisms responsible for disease progression and pathogenesis. To date, very few cellular factors involved in the life cycle of flaviviruses, which are important human pathogens, have been described. In this study, we demonstrate a crucial role for class II Arf proteins (Arf4 and Arf5) in the dengue flavivirus life cycle. We show that simultaneous depletion of Arf4 and Arf5 blocks recombinant subviral particle secretion for all four dengue serotypes. Immunostaining analysis suggests that class II Arf proteins are required at an early pre-Golgi step for dengue virus secretion. Using a horseradish peroxidase protein fused to a signal peptide, we show that class II Arfs act specifically on dengue virus secretion without altering the secretion of proteins through the constitutive secretory pathway. Co-immunoprecipitation data demonstrate that the dengue prM glycoprotein interacts with class II Arf proteins but not through its C-terminal VXPX motif. Finally, experiments performed with replication-competent dengue and yellow fever viruses demonstrate that the depletion of class II Arfs inhibits virus secretion, thus confirming their implication in the virus life cycle, although data obtained with West Nile virus pointed out the differences in virus-host interactions among flaviviruses. Our findings shed new light on a molecular mechanism used by dengue viruses during the late stages of the life cycle and demonstrate a novel function for class II Arf proteins.
authors: HKU-Pasteur Research Centre, University of Hong Kong, Hong Kong Special Administrative Region, China.
authors: Mateusz
authors: M
authors: Kudelko
authors: Unité des Interactions Moléculaires Flavivirus-Hôtes, Institut Pasteur, Paris, 75724, France.
authors: Jean-Baptiste
authors: JB
authors: Brault
authors: HKU-Pasteur Research Centre, University of Hong Kong, Hong Kong Special Administrative Region, China.
authors: Kevin
authors: K
authors: Kwok
authors: HKU-Pasteur Research Centre, University of Hong Kong, Hong Kong Special Administrative Region, China.
authors: Ming Yuan
authors: MY
authors: Li
authors: Unité des Interactions Moléculaires Flavivirus-Hôtes, Institut Pasteur, Paris, 75724, France.
authors: Nathalie
authors: N
authors: Pardigon
authors: HKU-Pasteur Research Centre, University of Hong Kong, Hong Kong Special Administrative Region, China; Department of Microbiology, University of Hong Kong, Hong Kong Special Administrative Region, China.
authors: J S Malik
authors: JSM
authors: Peiris
authors: HKU-Pasteur Research Centre, University of Hong Kong, Hong Kong Special Administrative Region, China; Department of Cell Biology and Infection, Institut Pasteur, 75724 Paris, France.
authors: Roberto
authors: R
authors: Bruzzone
authors: Unité des Interactions Moléculaires Flavivirus-Hôtes, Institut Pasteur, Paris, 75724, France.
authors: Philippe
authors: P
authors: Desprès
authors: HKU-Pasteur Research Centre, University of Hong Kong, Hong Kong Special Administrative Region, China; Department of Anatomy, University of Hong Kong, Hong Kong Special Administrative Region, China; Division of Biosciences, School of Health Sciences and Social Care, Brunel University, UB8 3PH London, United Kingdom. Electronic address: bnal@hku.hk.
authors: Béatrice
authors: B
authors: Nal
authors: HKU-Pasteur Research Centre, University of Hong Kong, Hong Kong Special Administrative Region, China. Electronic address: pgwang@hku.hk.
authors: Pei Gang
authors: PG
authors: Wang
mesh_terms: D020727:ADP-Ribosylation Factors / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001483:Base Sequence; D002460:Cell Line; D004274:DNA, Recombinant / Q000235:genetics; D003716:Dengue Virus / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D020868:Gene Silencing; D054884:Host-Pathogen Interactions; D006801:Humans; D008969:Molecular Sequence Data; D034741:RNA, Small Interfering / Q000235:genetics; D013045:Species Specificity; D014764:Viral Proteins / Q000737:chemistry / Q000378:metabolism; D014771:Virion / Q000235:genetics / Q000378:metabolism / Q000502:physiology
chemical_list: D004274:DNA, Recombinant; D034741:RNA, Small Interfering; D014764:Viral Proteins; D020727:ADP-Ribosylation Factors; C116688:ARF4 protein, human; C116691:ARF5 protein, human