Crystal Structure of the Oligomeric Form of Lassa Virus Matrix Protein Z

ABSTRACTThe arenavirus matrix protein Z is highly multifunctional and occurs in both monomeric and oligomeric forms. The crystal structure of a dodecamer of Z from Lassa virus, presented here, illustrates a ring-like structure with a highly basic center. Mutagenesis demonstrates that the dimeric interface within the dodecamer and a Lys-Trp-Lys triad at the center of the ring are important for oligomerization. This structure provides an additional template to explore the many functions of Z.IMPORTANCEThe arenavirus Lassa virus causes hundreds of thousands of infections each year, many of which develop into fatal hemorrhagic fever. The arenavirus matrix protein Z is multifunctional, with at least four distinct roles. Z exists in both monomeric and oligomeric forms, each of which likely serves a specific function in the viral life cycle. Here we present the dodecameric form of Lassa virus Z and demonstrate that Z forms a “wreath” with a highly basic center. This structure and that of monomeric Z now provide a pair of critical templates by which the multiple roles of Z in the viral life cycle may be interpreted.

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Effect of Strain Variations on Lassa Virus Z Protein-Mediated Human RIG-I Inhibition

Viruses ◽

10.3390/v12090907 ◽

2020 ◽

Vol 12 (9) ◽

pp. 907

Author(s):

Qinfeng Huang ◽

Xiaoying Liu ◽

Morgan Brisse ◽

Hinh Ly ◽

Yuying Liang

Keyword(s):

Matrix Protein ◽

Neurological Diseases ◽

Clinical Manifestations ◽

Hemorrhagic Fever ◽

Lassa Virus ◽

Type I ◽

Human Pathogens ◽

Protein Z ◽

Disease Heterogeneity ◽

Viral Virulence

Mammarenaviruses include several known human pathogens, such as the prototypic lymphocytic choriomeningitis virus (LCMV) that can cause neurological diseases and Lassa virus (LASV) that causes endemic hemorrhagic fever infection. LASV-infected patients show diverse clinical manifestations ranging from asymptomatic infection to hemorrhage, multi-organ failures and death, the mechanisms of which have not been well characterized. We have previously shown that the matrix protein Z of pathogenic arenaviruses, including LASV and LCMV, can strongly inhibit the ability of the innate immune protein RIG-I to suppress type I interferon (IFN-I) expression, which serves as a mechanism of viral immune evasion and virulence. Here, we show that Z proteins of diverse LASV isolates derived from rodents and humans have a high degree of sequence variations at their N- and C-terminal regions and produce variable degrees of inhibition of human RIG-I (hRIG-I) function in an established IFN-β promoter-driven luciferase (LUC) reporter assay. Additionally, we show that Z proteins of four known LCMV strains can also inhibit hRIG-I at variable degrees of efficiency. Collectively, our results confirm that Z proteins of pathogenic LASV and LCMV can inhibit hRIG-I and suggest that strain variations of the Z proteins can influence their efficiency to suppress host innate immunity that might contribute to viral virulence and disease heterogeneity.

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Host-Driven Phosphorylation Appears to Regulate the Budding Activity of the Lassa Virus Matrix Protein

Pathogens ◽

10.3390/pathogens7040097 ◽

2018 ◽

Vol 7 (4) ◽

pp. 97 ◽

Cited By ~ 3

Author(s):

Christopher Ziegler ◽

Philip Eisenhauer ◽

Inessa Manuelyan ◽

Marion Weir ◽

Emily Bruce ◽

...

Keyword(s):

Protein Function ◽

Matrix Protein ◽

Rna Virus ◽

Hemorrhagic Fever ◽

Polymerase Activity ◽

Lassa Fever ◽

Lassa Virus ◽

Protein Z ◽

Western Africa ◽

Z Protein

Lassa mammarenavirus (LASV) is an enveloped RNA virus that can cause Lassa fever, an acute hemorrhagic fever syndrome associated with significant morbidity and high rates of fatality in endemic regions of western Africa. The arenavirus matrix protein Z has several functions during the virus life cycle, including coordinating viral assembly, driving the release of new virus particles, regulating viral polymerase activity, and antagonizing the host antiviral response. There is limited knowledge regarding how the various functions of Z are regulated. To investigate possible means of regulation, mass spectrometry was used to identify potential sites of phosphorylation in the LASV Z protein. This analysis revealed that two serines (S18, S98) and one tyrosine (Y97) are phosphorylated in the flexible N- and C-terminal regions of the protein. Notably, two of these sites, Y97 and S98, are located in (Y97) or directly adjacent to (S98) the PPXY late domain, an important motif for virus release. Studies with non-phosphorylatable and phosphomimetic Z proteins revealed that these sites are important regulators of the release of LASV particles and that host-driven, reversible phosphorylation may play an important role in the regulation of LASV Z protein function.

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A Single Dose of Modified Vaccinia Ankara Expressing Lassa Virus-like Particles Protects Mice from Lethal Intra-cerebral Virus Challenge

Pathogens ◽

10.3390/pathogens8030133 ◽

2019 ◽

Vol 8 (3) ◽

pp. 133 ◽

Cited By ~ 8

Author(s):

Maria S. Salvato ◽

Arban Domi ◽

Camila Guzmán-Cardozo ◽

Sandra Medina-Moreno ◽

Juan Carlos Zapata ◽

...

Keyword(s):

Single Dose ◽

Matrix Protein ◽

Lethal Dose ◽

Health Impact ◽

Lassa Virus ◽

Protein Z ◽

Glycoprotein Precursor ◽

Lethal Challenge ◽

Virus Like Particles ◽

Virus Challenge

Lassa fever surpasses Ebola, Marburg, and all other hemorrhagic fevers except Dengue in its public health impact. Caused by Lassa virus (LASV), the disease is a scourge on populations in endemic areas of West Africa, where reported incidence is higher. Here, we report construction, characterization, and preclinical efficacy of a novel recombinant vaccine candidate GEO-LM01. Constructed in the Modified Vaccinia Ankara (MVA) vector, GEO-LM01 expresses the glycoprotein precursor (GPC) and zinc-binding matrix protein (Z) from the prototype Josiah strain lineage IV. When expressed together, GP and Z form Virus-Like Particles (VLPs) in cell culture. Immunogenicity and efficacy of GEO-LM01 was tested in a mouse challenge model. A single intramuscular dose of GEO-LM01 protected 100% of CBA/J mice challenged with a lethal dose of ML29, a Mopeia/Lassa reassortant virus, delivered directly into the brain. In contrast, all control animals died within one week. The vaccine induced low levels of antibodies but Lassa-specific CD4+ and CD8+ T cell responses. This is the first report showing that a single dose of a replication-deficient MVA vector can confer full protection against a lethal challenge with ML29 virus.

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Analysis of Assembly and Budding of Lujo Virus

Journal of Virology ◽

10.1128/jvi.03198-15 ◽

2015 ◽

Vol 90 (6) ◽

pp. 3257-3261 ◽

Cited By ~ 5

Author(s):

Shuzo Urata ◽

Jacqueline Weyer ◽

Nadia Storm ◽

Yukiko Miyazaki ◽

Petrus Jansen van Vuren ◽

...

Keyword(s):

Cell Surface ◽

Matrix Protein ◽

Hemorrhagic Fever ◽

Surface Glycoprotein ◽

Protein Z ◽

Glycoprotein Precursor ◽

Cell Surface Glycoprotein ◽

Particle Release ◽

Viral Release ◽

Virus Like Particle

The recently identified arenavirus Lujo virus (LUJV) causes fatal hemorrhagic fever in humans. We analyzed its mechanism of viral release driven by matrix protein Z and the cell surface glycoprotein precursor GPC. The L domains in Z are required for efficient virus-like particle release, but Tsg101, ALIX/AIP1, and Vps4A/B are unnecessary for budding. LUJV GPC is cleaved by site 1 protease (S1P) at the RKLM motif, and treatment with the S1P inhibitor PF-429242 reduced LUJV production.

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HIV-1 matrix protein: A mysterious regulator of the viral life cycle

Virus Research ◽

10.1016/j.virusres.2006.07.001 ◽

2007 ◽

Vol 124 (1-2) ◽

pp. 1-11 ◽

Cited By ~ 31

Author(s):

Alissa Bukrinskaya

Keyword(s):

Life Cycle ◽

Matrix Protein ◽

Protein A ◽

Viral Life Cycle ◽

Hiv 1

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Structure of nonstructural protein 1 from SARS-CoV-2.

Journal of Virology ◽

10.1128/jvi.02019-20 ◽

2020 ◽

Author(s):

Lauren K. Clark ◽

Todd J. Green ◽

Chad M. Petit

Keyword(s):

Crystal Structure ◽

Life Cycle ◽

High Resolution ◽

Nonstructural Protein ◽

Critical Role ◽

Viral Life Cycle ◽

Structure And Function ◽

Future Studies ◽

Nonstructural Protein 1 ◽

And Function

The periodic emergence of novel coronaviruses (CoVs) represents an ongoing public health concern with significant health and financial burden worldwide. The most recent occurrence originated in the city of Wuhan, China where a novel coronavirus (SARS-CoV-2) emerged causing severe respiratory illness and pneumonia. The continual emergence of novel coronaviruses underscores the importance of developing effective vaccines as well as novel therapeutic options that target either viral functions or host factors recruited to support coronavirus replication. The CoV nonstructural protein 1 (nsp1) has been shown to promote cellular mRNA degradation, block host cell translation, and inhibit the innate immune response to virus infection. Interestingly, deletion of the nsp1-coding region in infectious clones prevented the virus from productively infecting cultured cells. Because of nsp1’s importance in the CoV life cycle, it has been highlighted as a viable target for both antiviral therapy and vaccine development. However, the fundamental molecular and structural mechanisms that underlie nsp1 function remain poorly understood, despite its critical role in the viral life cycle. Here we report the high-resolution crystal structure of the amino, globular portion of SARS-CoV-2 nsp1 (residues 10 – 127) at 1.77 Å resolution. A comparison of our structure with the SARS-CoV-1 nsp1 structure reveals how mutations alter the conformation of flexible loops, inducing the formation of novel secondary structural elements and new surface features. Paired with the recently published structure of the carboxyl end of nsp1 (residues 148 – 180), our results provide the groundwork for future studies focusing on SARS-CoV-2 nsp1 structure and function during the viral life cycle. IMPORTANCE The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the causative agent for the COVID-19 pandemic. One protein known to play a critical role in the coronavirus life cycle is nonstructural protein1 (nsp1). As such, it has been highlighted in numerous studies as a target for both the development of antivirals and for the design of live-attenuated vaccines. Here we report the high-resolution crystal structure of nsp1 derived from SARS-CoV-2 at 1.77 Å resolution. This structure will facilitate future studies focusing on understanding the relationship between structure and function for nsp1. In turn, understanding these structure-function relationships will allow nsp1 to be fully exploited as a target for both antiviral development and vaccine design.

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Autophagy Promotes Infectious Particle Production of Mopeia and Lassa Viruses

Viruses ◽

10.3390/v11030293 ◽

2019 ◽

Vol 11 (3) ◽

pp. 293 ◽

Cited By ~ 6

Author(s):

Nicolas Baillet ◽

Sophie Krieger ◽

Alexandra Journeaux ◽

Valérie Caro ◽

Frédéric Tangy ◽

...

Keyword(s):

Matrix Protein ◽

Particle Production ◽

Defense Mechanism ◽

Viral Infections ◽

Hybrid Approach ◽

Hemorrhagic Fever ◽

Lassa Virus ◽

Infectious Particle ◽

Cellular Defense ◽

Infected Cells

Lassa virus (LASV) and Mopeia virus (MOPV) are two closely related Old-World mammarenaviruses. LASV causes severe hemorrhagic fever with high mortality in humans, whereas no case of MOPV infection has been reported. Comparing MOPV and LASV is a powerful strategy to unravel pathogenic mechanisms that occur during the course of pathogenic arenavirus infection. We used a yeast two-hybrid approach to identify cell partners of MOPV and LASV Z matrix protein in which two autophagy adaptors were identified, NDP52 and TAX1BP1. Autophagy has emerged as an important cellular defense mechanism against viral infections but its role during arenavirus infection has not been shown. Here, we demonstrate that autophagy is transiently induced by MOPV, but not LASV, in infected cells two days after infection. Impairment of the early steps of autophagy significantly decreased the production of MOPV and LASV infectious particles, whereas a blockade of the degradative steps impaired only MOPV infectious particle production. Our study provides insights into the role played by autophagy during MOPV and LASV infection and suggests that this process could partially explain their different pathogenicity.

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Structure of theReston ebolavirusVP30 C-terminal domain

Acta Crystallographica Section F Structural Biology Communications ◽

10.1107/s2053230x14003811 ◽

2014 ◽

Vol 70 (4) ◽

pp. 457-460 ◽

Cited By ~ 9

Author(s):

Matthew C. Clifton ◽

Robert N. Kirchdoerfer ◽

Kateri Atkins ◽

Jan Abendroth ◽

Amy Raymond ◽

...

Keyword(s):

Crystal Structure ◽

Life Cycle ◽

Hemorrhagic Fever ◽

Binding Domain ◽

Terminal Domain ◽

Dimeric Interface ◽

Reston Ebolavirus

The ebolaviruses can cause severe hemorrhagic fever. Essential to the ebolavirus life cycle is the protein VP30, which serves as a transcriptional cofactor. Here, the crystal structure of the C-terminal, NP-binding domain of VP30 fromReston ebolavirusis presented. Reston VP30 and Ebola VP30 both form homodimers, but the dimeric interfaces are rotated relative to each other, suggesting subtle inherent differences or flexibility in the dimeric interface.

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