12th International Retroviral Symposium: Assembly, Maturation and Uncoating

A special issue of Viruses (ISSN 1999-4915). This special issue belongs to the section "General Virology".

Deadline for manuscript submissions: closed (31 October 2024) | Viewed by 5920

Special Issue Editors


E-Mail Website
Guest Editor
University of Utah, Salt Lake City, UT, USA
Interests: RNA viruses assembly and replication; HIV; SARS-CoV-2; VSV;

E-Mail Website
Guest Editor
Department of Physics, Northeastern University, Boston, MA, USA
Interests: nucleic acid chaperone activity; retroviral capsid uncoating; nucleic-acid protein interactions; DNA condensation; single molecule biophysics
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
National Cancer Institute, Frederick, MD, USA
Interests: HIV; retrovirus; virus assembly; virus budding; maturation; envelope glycoproteins; Gag proteins; drug resistance; maturation inhibitors
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
IRIM CNRS, University of Montpellier, Montpellier, France
Interests: RNA envelopped viruses assembly; super resolution microscopy; HIV-1 assembly; CD4 T cell plasma membrane; viral proteins; host-cell lipids; sub-plasma membrane; pandemic Influenza H1N1; respiratory viruses; fluorescent replicative viruses; antiviral compounds; emerging SARS-CoV2; arboviruses
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
Department of Chemistry and Biochemistry, Ohio State University, Columbus, OH, USA
Interests: HIV and related retroviruses; retroviral assembly, genomic RNA packaging and host cell-viral interactions; protein-RNA interactions; aminoacyl-tRNA synthetases
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Between the 6th and 9th September 2023, a group of 95 scientists gathered at the Snowbird ski resort in the mountains outside Salt Lake City, Utah, for a conference focused on topics related to retroviral assembly, maturation, and early events in the virus replication cycle that are associated with maturation (e.g., nuclear import and uncoating of retroviral complexes). This conference had its genesis in what was originally named the International Retroviral Nucleocapsid Symposium (IRNCS). This meeting was launched in 1998 at the National Cancer Institute in Frederick Maryland, and was organized by Lou Henderson and Larry Arthur. The second meeting was subsequently held in Lyon, France (1999); the third in Annapolis, Maryland (2001); the fourth in Strasbourg, France (2003); the fifth in Montreal, Canada (2005); the sixth in Amsterdam, the Netherlands (2007); the seventh in Minneapolis, Minnesota (2009); and the eighth in Barcelona, Spain (2011). In 2013, its name changed slightly to reflect the broadening scope of the meeting: the ninth Retroviral Nucleocapsid Protein and Assembly Symposium was held in Montreal, Canada; the 10th in Montpelier, France (2016); and the 11th at Northeastern University in Boston, MA (2019). After a hiatus due to COVID-19, the 12th conference was held at Snowbird.This latest conference drew inspiration from the Retrovirus Assembly Meeting (RAM), which was held in Prague in the Czech Republic in 2000, 2004, and 2008, and was organized by, among others, Eric Hunter, Michaela Rumlova, and Tomas Ruml.

This 12th meeting was organized by the Guest Editors of this Special Issue: Saveez Saffarian, who served as the local and primary organizer; Delphine Muriaux, Mark Williams, Eric Freed and Karin Musier-Forsyth. The conference was arranged into a series of sessions: Envelope Incorporation, Structure, and Function; HIV-1 RNA Nuclear Trafficking, Packaging, and Translation; Virus Assembly Part I: Role of RNA and Membranes; Virus Assembly Part II; Therapeutic Strategies; Capsid Trafficking, Uncoating, and Integration; and Capsid Protein Structure and Function; Maturation; and Host Factors.

The Guest Editors of this Special Issue welcome submissions not only from conference attendees, but also from others with aligned research interests.

Dr. Saveez Saffarian
Dr. Mark C. Williams
Dr. Eric O. Freed
Dr. Delphine M. Muriaux
Dr. Karin Musier-Forsyth
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Viruses is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • retrovirus
  • HIV
  • virus assembly
  • virus budding
  • virus maturation
  • uncoating
  • capsid
  • nuclear pore
  • reverse transcription
  • integration
  • envelope glycoprotein
  • matrix
  • nucleocapsid
  • retroviral RNA
  • RNA trafficking
  • RNA packaging

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Published Papers (5 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

13 pages, 2386 KiB  
Article
Tsg101 UEV Interaction with Nedd4 HECT Relieves E3 Ligase Auto-Inhibition, Promoting HIV-1 Assembly and CA-SP1 Maturation Cleavage
by Susan M. Watanabe, David A. Nyenhuis, Mahfuz Khan, Lorna S. Ehrlich, Irene Ischenko, Michael D. Powell, Nico Tjandra and Carol A. Carter
Viruses 2024, 16(10), 1566; https://doi.org/10.3390/v16101566 - 2 Oct 2024
Viewed by 734
Abstract
Tsg101, a component of the endosomal sorting complex required for transport (ESCRT), is responsible for recognition of events requiring the machinery, as signaled by cargo tagging with ubiquitin (Ub), and for recruitment of downstream acting subunits to the site. Although much is known [...] Read more.
Tsg101, a component of the endosomal sorting complex required for transport (ESCRT), is responsible for recognition of events requiring the machinery, as signaled by cargo tagging with ubiquitin (Ub), and for recruitment of downstream acting subunits to the site. Although much is known about the latter function, little is known about its role in the earlier event. The N-terminal domain of Tsg101 is a structural homologue of Ub conjugases (E2 enzymes) and the protein associates with Ub ligases (E3 enzymes) that regulate several cellular processes including virus budding. A pocket in the domain recognizes a motif, PT/SAP, that permits its recruitment. PT/SAP disruption makes budding dependent on Nedd4L E3 ligases. Using HIV-1 encoding a PT/SAP mutation that makes budding Nedd4L-dependent, we identified as critical for rescue the residues in the catalytic (HECT) domain of the E3 enzyme that lie in proximity to sites in Tsg101 that bind Ub non-covalently. Mutation of these residues impaired rescue by Nedd4L but the same mutations had no apparent effect in the context of a Nedd4 isomer, Nedd4-2s, whose N-terminal (C2) domain is naturally truncated, precluding C2-HECT auto-inhibition. Surprisingly, like small molecules that disrupt Tsg101 Ub-binding, small molecules that interfered with Nedd4 substrate recognition arrested budding at an early stage, supporting the conclusion that Tsg101–Ub–Nedd4 interaction promotes enzyme activation and regulates Nedd4 signaling for viral egress. Tsg101 regulation of E3 ligases may underlie its broad ability to function as an effector in various cellular activities, including viral particle assembly and budding. Full article
Show Figures

Figure 1

10 pages, 4023 KiB  
Article
Kinetic Studies on the Interaction of HIV-1 Gag Protein with the HIV-1 RNA Packaging Signal
by Constance Rink, Tomas Kroupa, Siddhartha A. K. Datta and Alan Rein
Viruses 2024, 16(10), 1517; https://doi.org/10.3390/v16101517 - 25 Sep 2024
Viewed by 665
Abstract
During HIV-1 virus assembly, the genomic RNA (vRNA) is selected for packaging by the viral protein Gag because it contains a specific packaging signal, Psi. While there have been numerous studies of Gag–Psi interactions, there is almost no information on the kinetic aspects [...] Read more.
During HIV-1 virus assembly, the genomic RNA (vRNA) is selected for packaging by the viral protein Gag because it contains a specific packaging signal, Psi. While there have been numerous studies of Gag–Psi interactions, there is almost no information on the kinetic aspects of this interaction. We investigated the kinetics of Gag binding to different RNAs using switchSENSE DRX2 technology. We measured the association rate of Gag binding to monomeric Psi, to a “Multiple Binding Site Mutant” Psi that is inactive for genome packaging in vivo, and to a scrambled Psi. We discovered that Gag binds more rapidly to Psi RNA than to the mutant or scrambled RNAs. Furthermore, rapid Gag association kinetics are retained within sub-regions of Psi: Gag associates more rapidly with RNA containing only the 3′ two of the three Psi stem-loops than with monomeric RNA containing the 5′ two stem-loops or a scrambled RNA. No differences were detectable with individual Psi stem-loops. Interestingly, the rate of binding of Gag molecules to Psi increases with increasing Gag concentration, suggesting cooperativity in binding. The results are consistent with the hypothesis that selectivity in packaging derives from kinetic differences in initiation of particle assembly. Full article
Show Figures

Figure 1

15 pages, 7138 KiB  
Article
Arg18 Substitutions Reveal the Capacity of the HIV-1 Capsid Protein for Non-Fullerene Assembly
by Randall T. Schirra, Nayara F. B. dos Santos, Barbie K. Ganser-Pornillos and Owen Pornillos
Viruses 2024, 16(7), 1038; https://doi.org/10.3390/v16071038 - 27 Jun 2024
Cited by 1 | Viewed by 1312
Abstract
In the fullerene cone HIV-1 capsid, the central channels of the hexameric and pentameric capsomers each contain a ring of arginine (Arg18) residues that perform essential roles in capsid assembly and function. In both the hexamer and pentamer, the Arg18 rings coordinate inositol [...] Read more.
In the fullerene cone HIV-1 capsid, the central channels of the hexameric and pentameric capsomers each contain a ring of arginine (Arg18) residues that perform essential roles in capsid assembly and function. In both the hexamer and pentamer, the Arg18 rings coordinate inositol hexakisphosphate, an assembly and stability factor for the capsid. Previously, it was shown that amino-acid substitutions of Arg18 can promote pentamer incorporation into capsid-like particles (CLPs) that spontaneously assemble in vitro under high-salt conditions. Here, we show that these Arg18 mutant CLPs contain a non-canonical pentamer conformation and distinct lattice characteristics that do not follow the fullerene geometry of retroviral capsids. The Arg18 mutant pentamers resemble the hexamer in intra-oligomeric contacts and form a unique tetramer-of-pentamers that allows for incorporation of an octahedral vertex with a cross-shaped opening in the hexagonal capsid lattice. Our findings highlight an unexpected degree of structural plasticity in HIV-1 capsid assembly. Full article
Show Figures

Figure 1

20 pages, 3834 KiB  
Article
Cationic Residues of the HIV-1 Nucleocapsid Protein Enable DNA Condensation to Maintain Viral Core Particle Stability during Reverse Transcription
by Helena Gien, Michael Morse, Micah J. McCauley, Ioulia Rouzina, Robert J. Gorelick and Mark C. Williams
Viruses 2024, 16(6), 872; https://doi.org/10.3390/v16060872 - 29 May 2024
Viewed by 1063
Abstract
The HIV-1 nucleocapsid protein (NC) is a multifunctional viral protein necessary for HIV-1 replication. Recent studies have demonstrated that reverse transcription (RT) completes in the intact viral capsid, and the timing of RT and uncoating are correlated. How the small viral core stably [...] Read more.
The HIV-1 nucleocapsid protein (NC) is a multifunctional viral protein necessary for HIV-1 replication. Recent studies have demonstrated that reverse transcription (RT) completes in the intact viral capsid, and the timing of RT and uncoating are correlated. How the small viral core stably contains the ~10 kbp double stranded (ds) DNA product of RT, and the role of NC in this process, are not well understood. We showed previously that NC binds and saturates dsDNA in a non-specific electrostatic binding mode that triggers uniform DNA self-attraction, condensing dsDNA into a tight globule against extending forces up to 10 pN. In this study, we use optical tweezers and atomic force microscopy to characterize the role of NC’s basic residues in dsDNA condensation. Basic residue mutations of NC lead to defective interaction with the dsDNA substrate, with the constant force plateau condensation observed with wild-type (WT) NC missing or diminished. These results suggest that NC’s high positive charge is essential to its dsDNA condensing activity, and electrostatic interactions involving NC’s basic residues are responsible in large part for the conformation, size, and stability of the dsDNA-protein complex inside the viral core. We observe DNA re-solubilization and charge reversal in the presence of excess NC, consistent with the electrostatic nature of NC-induced DNA condensation. Previous studies of HIV-1 replication in the presence of the same cationic residue mutations in NC showed significant defects in both single- and multiple-round viral infectivity. Although NC participates in many stages of viral replication, our results are consistent with the hypothesis that cationic residue mutations inhibit genomic DNA condensation, resulting in increased premature capsid uncoating and contributing to viral replication defects. Full article
Show Figures

Figure 1

Review

Jump to: Research

25 pages, 5680 KiB  
Review
The Assembly of HTLV-1—How Does It Differ from HIV-1?
by Dominik Herrmann, Shuyu Meng, Huixin Yang, Louis M. Mansky and Jamil S. Saad
Viruses 2024, 16(10), 1528; https://doi.org/10.3390/v16101528 - 27 Sep 2024
Viewed by 1626
Abstract
Retroviral assembly is a highly coordinated step in the replication cycle. The process is initiated when the newly synthesized Gag and Gag-Pol polyproteins are directed to the inner leaflet of the plasma membrane (PM), where they facilitate the budding and release of immature [...] Read more.
Retroviral assembly is a highly coordinated step in the replication cycle. The process is initiated when the newly synthesized Gag and Gag-Pol polyproteins are directed to the inner leaflet of the plasma membrane (PM), where they facilitate the budding and release of immature viral particles. Extensive research over the years has provided crucial insights into the molecular determinants of this assembly step. It is established that Gag targeting and binding to the PM is mediated by interactions of the matrix (MA) domain and acidic phospholipids such as phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2). This binding event, along with binding to viral RNA, initiates oligomerization of Gag on the PM, a process mediated by the capsid (CA) domain. Much of the previous studies have focused on human immunodeficiency virus type 1 (HIV-1). Although the general steps of retroviral replication are consistent across different retroviruses, comparative studies revealed notable differences in the structure and function of viral components. In this review, we present recent findings on the assembly mechanisms of Human T-cell leukemia virus type 1 and highlight key differences from HIV-1, focusing particularly on the molecular determinants of Gag–PM interactions and CA assembly. Full article
Show Figures

Figure 1

Back to TopTop