Maturation-induced Conformational Changes of HIV-1 Capsid Protein and Identification of Two High Affinity Sites for Cyclophilins in the C-terminal Domain

ABSTRACT A novel fibronectin-based protein (Adnectin) HIV-1 inhibitor was generated using in vitro selection. This inhibitor binds to human CD4 with a high affinity (3.9 nM) and inhibits viral entry at a step after CD4 engagement and preceding membrane fusion. The progenitor sequence of this novel inhibitor was selected from a library of trillions of Adnectin variants using mRNA display and then further optimized for improved antiviral and physical properties. The final optimized inhibitor exhibited full potency against a panel of 124 envelope (gp160) proteins spanning 11 subtypes, indicating broad-spectrum activity. Resistance profiling studies showed that this inhibitor required 30 passages (151 days) in culture to acquire sufficient resistance to result in viral titer breakthrough. Resistance mapped to the loss of multiple potential N-linked glycosylation sites in gp120, suggesting that inhibition is due to steric hindrance of CD4-binding-induced conformational changes.

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A triclinic crystal structure of the carboxy-terminal domain of HIV-1 capsid protein with four molecules in the asymmetric unit reveals a novel packing interface

Acta Crystallographica Section F Structural Biology and Crystallization Communications ◽

10.1107/s1744309113011871 ◽

2013 ◽

Vol 69 (6) ◽

pp. 602-606 ◽

Cited By ~ 4

Author(s):

Ayala Lampel ◽

Oren Yaniv ◽

Or Berger ◽

Eran Bacharach ◽

Ehud Gazit ◽

...

Keyword(s):

Crystal Structure ◽

Capsid Protein ◽

Asymmetric Unit ◽

Terminal Domain ◽

Carboxy Terminal Domain ◽

Carboxy Terminal ◽

Hiv 1

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Escherichia coli LysU is a potential surrogate for human lysyl tRNA synthetase in interactions with the C-terminal domain of HIV-1 capsid protein

Organic & Biomolecular Chemistry ◽

10.1039/c2ob26499d ◽

2013 ◽

Vol 11 (4) ◽

pp. 612-620 ◽

Cited By ~ 3

Author(s):

Nonlawat Boonyalai ◽

James R. Pullen ◽

Mohd Firdaus Abdul Wahab ◽

Michael Wright ◽

Andrew D. Miller

Keyword(s):

Escherichia Coli ◽

Capsid Protein ◽

Trna Synthetase ◽

Terminal Domain ◽

Hiv 1

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HIV-1 Capsid Protein Forms Spherical (Immature-Like) and Tubular (Mature-Like) Particles in Vitro: Structure Switching by pH-induced Conformational Changes

Biophysical Journal ◽

10.1016/s0006-3495(01)75725-6 ◽

2001 ◽

Vol 81 (1) ◽

pp. 586-594 ◽

Cited By ~ 68

Author(s):

Lorna S. Ehrlich ◽

Tianbo Liu ◽

Suzanne Scarlata ◽

Benjamin Chu ◽

Carol A. Carter

Keyword(s):

Capsid Protein ◽

Conformational Changes ◽

Structure Switching ◽

Hiv 1

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Structural determinants of virion assembly and release in the C-terminus of the M-PMV capsid protein

Journal of Virology ◽

10.1128/jvi.00615-21 ◽

2021 ◽

Author(s):

Marlene V. Buckmaster ◽

Kaneil K. Zadrozny ◽

Barbie K. Ganser-Pornillos ◽

Owen Pornillos ◽

Stephen P. Goff

Keyword(s):

Capsid Protein ◽

Conformational Changes ◽

Structural Determinants ◽

Particle Assembly ◽

Gag Protein ◽

Virion Assembly ◽

C Terminus ◽

Hiv 1

The transition from an immature to a fully infectious mature retrovirus particle is associated with molecular switches that trigger dramatic conformational changes in the structure of the Gag proteins. A dominant maturation switch that stabilizes the immature capsid lattice is located downstream of the capsid (CA) protein in many retroviral Gags. The HIV-1 Gag contains a stretch of five amino acid residues termed the ‘clasp motif’, important for the organization of the hexameric subunits that provide stability to the overall immature HIV-1 shell. Sequence alignment of the CA C-terminal domains (CTDs) of the HIV-1 and Mason-Pfizer Monkey Virus (M-PMV) highlighted a spacer-like domain in M-PMV that may provide comparable function. The importance of the sequences spanning the CA-NC cleavage has been demonstrated by mutagenesis, but the specific requirements for the clasp motif in several steps of M-PMV particle assembly and maturation have not been determined in detail. In the present study we report an examination of the role of the clasp motif in the M-PMV life cycle. We generated a series of M-PMV Gag mutants and assayed for assembly of the recombinant protein in vitro , and for the assembly, maturation, release, genomic RNA packaging, and infectivity of the mutant virus in vivo . The mutants revealed major defects in virion assembly and release in 293T and HeLa cells, and even larger defects in infectivity. Our data identifies the clasp motif as a fundamental contributor to CA-CTD interactions necessary for efficient viral infection. Importance The C-terminal domain of the capsid protein of many retroviruses has been shown to be critical for virion assembly and maturation, but the functions of this region of M-PMV are uncertain. We show that a short ‘clasp’ motif in the capsid domain of the M-PMV Gag protein plays a key role in M-PMV virion assembly, genome packaging, and infectivity.

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Backbone Dynamics of the N-Terminal Domain of the HIV-1 Capsid Protein and Comparison with the G94D Mutant Conferring Cyclosporin Resistance/Dependence†

Biochemistry ◽

10.1021/bi990991x ◽

1999 ◽

Vol 38 (32) ◽

pp. 10262-10271 ◽

Cited By ~ 22

Author(s):

Ramón Campos-Olivas ◽

Michael F. Summers

Keyword(s):

Capsid Protein ◽

Backbone Dynamics ◽

Terminal Domain ◽

Hiv 1

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HIV-1 Virus Interactions With Host Proteins: Interaction of the N-terminal Domain of the HIV-1 Capsid Protein With Human Calmodulin

Natural Product Communications ◽

10.1177/1934578x19849190 ◽

2019 ◽

Vol 14 (5) ◽

pp. 1934578X1984919

Author(s):

Ywh-Min Tzou ◽

Ronald Shin ◽

N. Rama Krishna

Keyword(s):

Capsid Protein ◽

Host Factors ◽

Host Proteins ◽

Terminal Domain ◽

Immunodeficiency Virus ◽

Infected Cells ◽

Virus Interactions ◽

Precise Role ◽

Hiv 1

The human immunodeficiency virus (HIV-1 virus) exploits several host factors for assembly, infection, and replication within the infected cells. In this work, we describe the evidence for an interaction of the N-terminal domain of the HIV-1 capsid protein with human calmodulin. The precise role of this interaction within the life cycle of the HIV-1 virus is yet to be defined. Potential roles for this interaction in the viral capsid uncoating are discussed.

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