Dynamic conformational changes in the rhesus TRIM5α dimer dictate the potency of HIV-1 restriction.
The TRIM5α protein from rhesus macaques (rhTRIM5α) mediates a potent inhibition of HIV-1 infection via a mechanism that involves the abortive disassembly of the viral core. We have demonstrated that alpha-helical elements within the Linker 2 (L2) region, which lies between the SPRY domain and the Coiled-Coil domain, influence the potency of restriction. Here, we utilize single-molecule FRET analysis to reveal that the L2 region of the TRIM5α dimer undergoes dynamic conformational changes, which results in the displacement of L2 regions by 25 angstroms relative to each other. Analysis of restriction enhancing or abrogating mutations in the L2 region reveal that restriction defective mutants are unable to undergo dynamic conformational changes and do not assume compact, alpha-helical conformations in the L2 region. These data suggest a model in which conformational changes in the L2 region mediate displacement of CA bound SPRY domains to induce the destabilization of assembled capsid during restriction.
Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA.
Rajan
R
Lamichhane
Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Chicago, IL, USA.
Santanu
S
Mukherjee
Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Chicago, IL, USA.
Nikolai
N
Smolin
Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA.
Raymond F
RF
Pauszek
Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Chicago, IL, USA.
Margret
M
Bradley
Viral Mutation Section, HIV Dynamics and Replication Program, National Cancer Institute at Frederick, Frederick, MD, USA.
Jaya
J
Sastri
Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Chicago, IL, USA.
Seth L
SL
Robia
Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA.
David
D
Millar
Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Chicago, IL, USA.
Edward M
EM
Campbell
D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology*; D002460:Cell Line; D019281:Dimerization; D004195:Disease Models, Animal; D015658:HIV Infections / Q000235:genetics / Q000276:immunology* / Q000821:virology; D015497:HIV-1 / Q000235:genetics / Q000502:physiology*; D006801:Humans; D008253:Macaca mulatta / Q000235:genetics / Q000276:immunology* / Q000821:virology; D009154:Mutation; D011487:Protein Conformation
D002352:Carrier Proteins
Coiled coil; Dimer; HIV-1; Molecular dynamics simulation; Restriction factor; Single molecule FRET; TRIM5alpha; Tripartite Motif; smFRET