Retroviruses assemble and bud from infected cells in an immature form and require proteolytic maturation for infectivity. The CA (capsid) domains of the Gag polyproteins assemble a protein lattice as a truncated sphere in the immature virion. Proteolytic cleavage of Gag induces dramatic structural rearrangements; a subset of cleaved CA subsequently assembles into the mature core, whose architecture varies among retroviruses. Murine leukemia virus (MLV) is the prototypical γ-retrovirus and serves as the basis of retroviral vectors, but the structure of the MLV CA layer is unknown. Here we have combined X-ray crystallography with cryoelectron tomography to determine the structures of immature and mature MLV CA layers within authentic viral particles. This reveals the structural changes associated with maturation, and, by comparison with HIV-1, uncovers conserved and variable features. In contrast to HIV-1, most MLV CA is used for assembly of the mature core, which adopts variable, multilayered morphologies and does not form a closed structure. Unlike in HIV-1, there is similarity between protein-protein interfaces in the immature MLV CA layer and those in the mature CA layer, and structural maturation of MLV could be achieved through domain rotations that largely maintain hexameric interactions. Nevertheless, the dramatic architectural change on maturation indicates that extensive disassembly and reassembly are required for mature core growth. The core morphology suggests that wrapping of the genome in CA sheets may be sufficient to protect the MLV ribonucleoprotein during cell entry.
- MeSH
- elektronová kryomikroskopie MeSH
- genové produkty gag chemie genetika ultrastruktura MeSH
- HEK293 buňky MeSH
- HIV-1 chemie genetika ultrastruktura MeSH
- kapsida chemie ultrastruktura MeSH
- krystalografie rentgenová MeSH
- kvarterní struktura proteinů MeSH
- lidé MeSH
- molekulární modely MeSH
- myši MeSH
- proteinové domény MeSH
- sekvence aminokyselin MeSH
- sekvenční homologie aminokyselin MeSH
- tomografie elektronová MeSH
- virion chemie genetika ultrastruktura MeSH
- virové plášťové proteiny chemie genetika ultrastruktura MeSH
- virus myší leukemie chemie genetika ultrastruktura MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Intramural MeSH
- srovnávací studie MeSH
Assembly of human immunodeficiency virus (HIV-1) represents an attractive target for antiretroviral therapy which is not exploited by currently available drugs. We established high-throughput screening for assembly inhibitors based on competition of small molecules for the binding of a known dodecapeptide assembly inhibitor to the C-terminal domain of HIV-1 CA (capsid). Screening of >70000 compounds from different libraries identified 2-arylquinazolines as low micromolecular inhibitors of HIV-1 capsid assembly. We prepared focused libraries of modified 2-arylquinazolines and tested their capacity to bind HIV-1 CA to compete with the known peptide inhibitor and to prevent the replication of HIV-1 in tissue culture. Some of the compounds showed potent binding to the C-terminal domain of CA and were found to block viral replication at low micromolar concentrations.
- MeSH
- chinazoliny chemická syntéza chemie farmakologie MeSH
- HIV-1 účinky léků metabolismus MeSH
- kapsida účinky léků metabolismus MeSH
- knihovny malých molekul MeSH
- látky proti HIV metabolismus farmakologie MeSH
- lidé MeSH
- molekulární modely MeSH
- rekombinantní proteiny biosyntéza MeSH
- replikace viru účinky léků MeSH
- reprodukovatelnost výsledků MeSH
- rychlé screeningové testy MeSH
- termodynamika MeSH
- viabilita buněk účinky léků MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH