Maramorosch / Mettenleiter Advances in Virus Research

1. Auflage 2015
ISBN: 978-0-12-802425-6
Verlag: Elsevier Science & Techn.
Format: EPUB
Kopierschutz: Adobe DRM (»Systemvoraussetzungen)

E-Book, Englisch, Band Volume 92, 270 Seiten

Reihe: Advances in Virus Research

Published since 1953, Advances in Virus Research covers a diverse range of in-depth reviews, providing a valuable overview of the current field of virology. - Contributions from leading authorities - Informs and updates on all the latest developments in the field

Autoren/Hrsg.

Maramorosch, Karl

Mettenleiter, Thomas

Inhaltsverzeichnis

1;Front Cover;1
2;Advances in Virus Research;4
3;Copyright;5
4;Dedication;6
5;Contents;8
6;Contributors;10
7;Chapter 1: Comparison of Lipid-Containing Bacterial and Archaeal Viruses;12
7.1;1. Introduction;13
7.1.1;1.1. Origin of lipids in prokaryotic viruses and their detection;14
7.2;2. Function and Significance of Lipids in Prokaryotic Virus Life Cycle;29
7.2.1;2.1. How prokaryotic viruses acquire their lipids;32
7.2.1.1;2.1.1. Viruses with an external membrane;32
7.2.1.2;2.1.2. Viruses with a membrane underneath the icosahedral capsid;33
7.2.1.3;2.1.3. Viruses with lipids as structural protein modifications;34
7.3;3. Currently Known Lipid-Containing Bacterial and Archaeal Viruses;35
7.3.1;3.1. Icosahedral viruses with an inner membrane;35
7.3.1.1;3.1.1. Lipids in the corticovirus PM2 with a circular supercoiled dsDNA genome;36
7.3.1.2;3.1.2. Lipids in PRD1 and related viruses;38
7.3.1.3;3.1.3. Lipids of PRD1 form an icosahedrally ordered membrane;39
7.3.1.4;3.1.4. PRD1 genome delivery occurs through a membranous tunneling nanotube;40
7.3.1.5;3.1.5. Assembly and packaging of internal membrane-containing bacteriophage PRD1;42
7.3.2;3.2. Enveloped icosahedral viruses: Phage .6 and its relatives;43
7.3.2.1;3.2.1. Involvement of the membranes in .6 entry;44
7.3.2.2;3.2.2. How .6 acquires its membrane envelope;45
7.3.2.3;3.2.3. Lipids of the .6 virion and its host;46
7.3.3;3.3. Vesicular pleomorphic viruses;46
7.3.3.1;3.3.1. Asymmetric lipid vesicles as viruses;48
7.3.3.2;3.3.2. Bacterial vesicular viruses;50
7.3.4;3.4. Prokaryotic viruses with helical symmetry: With or without a membrane;51
7.3.4.1;3.4.1. Lipothrixviruses: Helical viruses with a membrane envelope;51
7.3.4.1.1;3.4.1.1. Alphalipothrixviruses;52
7.3.4.1.2;3.4.1.2. Betalipothrixviruses;52
7.3.4.1.3;3.4.1.3. Gammalipothrixviruses and deltalipothrixviruses;53
7.3.5;3.5. Lemon-shaped viruses are specific for archaea;54
7.3.5.1;3.5.1. Viruses with one short tail;54
7.3.5.2;3.5.2. Viruses with one or two long tails;56
7.3.6;3.6. Archaeal spherical viruses with helical NCs have an envelope;57
7.4;4. Conclusions;58
7.5;Acknowledgments;60
7.6;References;60
8;Chapter 2: Innate Recognition of Alphaherpesvirus DNA;74
8.1;1. Introduction;75
8.1.1;1.1. Alphaherpesviruses;75
8.1.2;1.2. Immunity to alphaherpesviruses;77
8.1.3;1.3. Innate DNA sensing;78
8.2;2. DNA Sensors;81
8.2.1;2.1. TLR9;81
8.2.2;2.2. Discovery of intracellular DNA sensors;86
8.2.3;2.3. DAI;86
8.2.4;2.4. AIM2;88
8.2.5;2.5. IFI16;89
8.2.6;2.6. cGAS;92
8.2.7;2.7. RNA Pol III and RIG-I;94
8.3;3. Accessibility of Viral DNA to DNA Sensors;95
8.4;4. Evasion of DNA-Induced Signaling;96
8.5;5. Relevance for Vaccine Design;99
8.6;6. Conclusions and Future Perspective;101
8.7;References;102
9;Chapter 3: Molecular Biology of Potyviruses;112
9.1;1. Introduction;113
9.2;2. Genera of the Family Potyviridae and the Main Differences in Genome Structures;114
9.3;3. Biological and Biochemical Features of Potyviral Proteins;116
9.3.1;3.1. P1;117
9.3.2;3.2. HCPro;118
9.3.3;3.3. P3, 6K1, and PIPO;125
9.3.4;3.4. CI;126
9.3.5;3.5. 6K2 and NIa;127
9.3.6;3.6. NIb;128
9.3.7;3.7. CP;129
9.4;4. Virus Multiplication;130
9.4.1;4.1. Subcellular localization of potyvirus multiplication;130
9.4.2;4.2. Viral and plant factors involved in potyvirus multiplication;132
9.4.3;4.3. Putative functions of these factors during potyvirus multiplication;136
9.5;5. Virus Movement;139
9.5.1;5.1. Intracellular and cell-to-cell movements;139
9.5.2;5.2. Long-distance movement;143
9.5.2.1;5.2.1. Viral determinants involved in potyviral long-distance movement;145
9.5.2.2;5.2.2. Host factors involved in the restriction of long-distance movement;147
9.6;6. Virus Transmission;149
9.6.1;6.1. Transmission by aphids;149
9.6.2;6.2. Seed transmission;153
9.7;7. Plant/Potyvirus Interactions in Compatible Pathosystems;155
9.7.1;7.1. Evolutionary abilities of potyviruses to adapt to their hosts;156
9.7.2;7.2. HCPro: A key pathogenicity determinant as suppressor of RNA silencing;163
9.7.3;7.3. Symptomatology;166
9.8;8. Biotechnological Applications of Potyviruses;176
9.9;9. Concluding Remarks;177
9.10;Acknowledgments;178
9.11;Note Added in Proof;178
9.12;References;178
10;Chapter 4: Immune Evasion Strategies of Molluscum Contagiosum Virus;212
10.1;1. Introduction;213
10.2;2. Characteristics of the MCV Genome and Insights into MCV Replication;214
10.3;3. MC Lesion Development;215
10.4;4. Characterization of MC Lesions;217
10.4.1;4.1. Initial stages of infection;217
10.4.2;4.2. Host cell response to MCV infection;218
10.5;5. Immune Responses to MCV Infection;219
10.6;6. MCV Epidemiology;220
10.7;7. MCV Diagnosis and Treatment;222
10.8;8. Current Roadblocks in Propagating MCV in Tissue Culture Systems;223
10.9;9. MCV Immune Evasion Mechanisms;225
10.10;10. Limitations and Caveats When Studying MCV Immune Evasion Proteins;225
10.11;11. The FLIP Family of Viral and Cellular Proteins;227
10.11.1;11.1. Introduction to FLIPs;227
10.11.2;11.2. Signaling events triggered by the TNFR1;227
10.11.2.1;11.2.1. Discovery of viral and cellular homologs of procaspase-8;229
10.11.2.2;11.2.2. MC159 and inhibition of apoptosis;231
10.11.2.3;11.2.3. MC160 and apoptosis;233
10.11.2.4;11.2.4. Gammaherpesvirus FLIPs and inhibition of apoptosis;234
10.11.2.5;11.2.5. cFLIP and apoptosis;235
10.11.3;11.3. The FLIP family and control of NF-.B activation;237
10.11.3.1;11.3.1. MC159: A protein that inhibits NF-.B activation;237
10.11.3.2;11.3.2. MC160, an NF-.B-inhibitory protein;239
10.11.3.3;11.3.3. The K13 vFLIP is an NF-.B-activating protein;240
10.11.3.4;11.3.4. cFLIPs and their functions in regulating NF-.B activation;242
10.11.4;11.4. The FLIP Family and Control of IRF3 Activation;243
10.11.4.1;11.4.1. MC159 and inhibition of IRF3;244
10.11.4.2;11.4.2. MC160 and inhibition of IRF3;245
10.11.4.3;11.4.3. cFLIP and inhibition of IRF3;245
10.12;12. Other MCV Immune Evasion Molecules;246
10.12.1;12.1. MCV MC54, an IL-18-binding protein;246
10.12.2;12.2. MCV MC148, a viral chemokine;247
10.12.3;12.3. MCV MC007, a pRb-binding protein;248
10.12.4;12.4. MC66, a glutathione peroxidase homolog;248
10.13;13. Conclusions;249
10.14;References;249
11;Index;264
12;Color Plate;272

Leseproben

Chapter Two Innate Recognition of Alphaherpesvirus DNA
Stefanie Luecke*; Søren R. Paludan†,‡,1    * Graduate School of Life Sciences, Universiteit Utrecht, Utrecht, The Netherlands
† Department of Biomedicine, Aarhus University, Aarhus, Denmark
‡ Aarhus Research Center for Innate Immunology, Aarhus University, Aarhus, Denmark
1 Corresponding author: email address: [e-mail] Abstract
Alphaherpesviruses include human and animal pathogens, such as herpes simplex virus type 1, which establish life-long latent infections with episodes of recurrence. The immunocompetence of the infected host is an important determinant for the outcome of infections with alphaherpesviruses. Recognition of pathogen-associated molecular patterns by pattern recognition receptors is an essential, early step in the innate immune response to pathogens. In recent years, it has been discovered that herpesvirus DNA is a strong inducer of the innate immune system. The viral genome can be recognized in endosomes by TLR9, as well as intracellularly by a variety of DNA sensors, the best documented being cGAS, RNA Pol III, IFI16, and AIM2. These DNA sensors use converging signaling pathways to activate transcription factors, such as IRF3 and NF-?B, which induce the expression of type I interferons and other inflammatory cytokines and activate the inflammasome. This review summarizes the recent literature on the innate sensing of alphaherpesvirus DNA, the mechanisms of activation of the different sensors, their mechanisms of signal transduction, their physiological role in defense against herpesvirus infection, and how alphaherpesviruses seek to evade these responses to allow establishment and maintenance of infection. Keywords Alphaherpesviruses HSV-1 TLR9 STING Type I interferon 1 Introduction
1.1 Alphaherpesviruses
The Herpesviridae family comprises more than 130 virus species, which infect mammals, birds, and reptiles. Herpesviruses are enveloped, double-stranded DNA viruses (Fig. 1A), which usually lyse productively infected cells and establish latent infections in their hosts. Eight herpesviruses are known to cause disease in humans, most notably in children and immunocompromised individuals. The family is divided into three subfamilies, alpha-, beta-, and gamma-herpesviruses. This division was originally based on biological similarities and later confirmed by genome sequencing (Pellett & Roizman, 2013). Figure 1 Alphaherpesvirus structure and entry. (A) Structure of the alphaherpesvirus virion. The linear dsDNA genome is surrounded by an icosahedral capsid. Associated with the vertices of the capsid are the inner tegument proteins, which are surrounded by the outer tegument. The lipid bilayer envelope contains multiple viral glycoproteins. (B) Schematic illustration of alphaherpesviral cell entry, nuclear DNA delivery, and exposure to DNA sensors. The virion attaches to the cell surface through interaction of the glycoproteins with cellular receptors. The virus can enter the cell via two pathways: by direct fusion of the viral envelope with the plasma membrane or by endocytosis and subsequent fusion of envelope and endosomal membrane. The capsid is transported along microtubules toward the microtubule organizing center (MTOC) near the nucleus. The capsid then docks at a nuclear pore, and the viral genome is released into the nucleus. In the nucleus, the viral genome circularizes and lytic or latent infection takes place. Viral DNA is exposed to endosomal DNA sensors via endosomal entry or by autophagocytic delivery of cytosolic capsids to endosomes, to cytosolic sensors by proteasomal degradation of the capsid, and to nuclear sensors by nuclear DNA delivery. Alphaherpesviruses are characterized by a relatively broad host range and fast reproduction during lytic infection compared to other herpesviruses (Pellett & Roizman, 2013). They contain three virus species pathogenic to humans (herpes simplex virus type 1 (HSV-1, also called human herpesvirus 1), herpes simplex virus type 2 (HSV-2, also called human herpesvirus 2), and varicella zoster virus (VZV, also called human herpesvirus 3)) and many pathogens of veterinary importance, notably Marek's disease virus (MDV, also called gallid herpesvirus 2) and pseudorabies virus (PRV, also called suid herpesvirus 1). Herpes simplex viruses are ubiquitous human pathogens, which lytically infect epithelial cells of mucosal surfaces and the skin and afterward establish latency in the cell bodies of peripheral sensory neurons innervating the infected area. During latency, the viral genome persists in the nucleus of the host while the majority of viral genes are silenced. It can be maintained for the lifetime of the host organism. Reactivation from latency can be induced by a number of factors, including tissue damage, UV radiation, immune status changes, and stress, but can also occur spontaneously. In reactivation, virus particles produced in the neuronal cell body are transported along the axons by anterograde transport and infect epithelial cells again. HSV-1 usually causes recurrent cold sores at the lips (herpes labialis), while HSV-2 is often responsible for genital herpes infections (herpes genitalis). HSV may also spread to the central nervous system, leading to herpes encephalitis, cause disseminating herpes infections in neonates and immunocompromised individuals, and infect the eyes, often leading to blindness (Roizman, Knipe, & Whitley, 2013). VZV is the causal agent of chicken pox after primary infection and of shingles (herpes zoster) upon reactivation. In primary infection, the virus usually infects epithelial cells in the upper respiratory tract followed by infection of T cells in lymphoid tissues. This allows for transport of the virus to skin areas over the whole body, where viral replications result in the characteristic rash. VZV then establishes latency in peripheral sensory neurons. The virus can reactivate to cause shingles, which may be associated with serious neurological complications (Arvin & Gilden, 2013). PRV first infects epithelial cells of the respiratory tract and then establishes latency in sensory neurons. The natural hosts for this virus are pigs, but it can also infect many other mammals such as cattle, sheep, and dogs. It is the causative agent of Aujeszky's disease, which is characterized by symptoms ranging from high mortality and severe central nervous system defects in suckling piglets, via abortions and stillbirths in pregnant sows, to fever and respiratory symptoms in adult pigs (Pomeranz, Reynolds, & Hengartner, 2005). MDV establishes latency in and causes oncogenic transformation of immune cells, especially CD4+ T cells, and lytically infects epithelial cells of inner organs and the skin in chickens, leading to a variety of clinical symptoms including chronic polyneuritis and visceral lymphoma (Osterrieder, Kamil, Schumacher, Tischer, & Trapp, 2006). Herpesviruses enter their host cells by fusion of the viral lipid envelope with the plasma or endosomal membrane, which is initiated by interaction of viral glycoproteins in the virion envelope with cell surface receptors. Upon viral entry, the tegument proteins, located between the viral envelope and the capsid, are released into the cytoplasm and interact with host factors to create a favorable environment for the virus. In permissive cells, i.e., cells that allow productive replication of the virus, the icosahedral capsid containing the viral dsDNA genome moves along the microtubule network toward the nucleus, where the viral DNA is translocated through the nuclear pores. In the nucleus, the viral genome circularizes (Fig. 1). Silencing of viral gene expression can lead to the establishment of latent infection. During lytic infection, expression of viral genes takes place in three stages, immediate-early (responsible for subsequent viral gene expression and immune evasion), early (replication of viral DNA), and late (formation and release of progeny virions), and eventually leads to multiplication of the viral genome and to assembly and release of new virus particles (Arvin & Gilden, 2013; Roizman et al., 2013). However, some cells, such as macrophages in case of HSV-1, are nonpermissive for the virus, i.e., productive replication does not take place. Even in permissive cells, not all viral particles lead to productive infection. It is suspected that this is partly due to the early innate antiviral response of the cells (Paludan, Bowie, Horan, & Fitzgerald, 2011). 1.2 Immunity to alphaherpesviruses
As with most infectious diseases, immunity to alphaherpesviruses relies on innate and adaptive immune responses. One of the first responses upon detection of a herpesvirus in an infected cell is the production and secretion of interferons (IFNs), especially type I (IFNa and IFNß), but also type III (e.g., IFN?), and other proinflammatory cytokines and chemokines (Ank et al., 2008; Egan, Wu, Wigdahl, & Jennings, 2013). By paracrine and autocrine signaling, IFNs mediate a number of antiviral activities in infected and neighboring cells by the induction and expression of a variety of genes (interferon-stimulated genes, ISGs)...