Here, the longawaited structure of the fulllength integrase complex is. May 11, 2012 retroviral integration intermediates and detection of 3processing and strand transfer in crystallo. Retroviral integrase proteins and hiv1 dna integration. Two unique features of retroviruses are their genome organization and strategies for gene expression. Structural basis for strandtransfer inhibitor binding to. Integrase cleaves specific phosphodiester bonds near the viral dna ends during the 3. The intasome showed significant conformational flexibility in its overall architecture as well as the interactions of an hiv1 in strand transfer inhibitor insti in the active site. Structural biology of hiv integrase strand transfer inhibitors. While some resistancerelated mutations occur near the inhibitor s binding site, the mutation n155h occurs on the. In strand transfer inhibitors instis bind to the indna complex after. Louis as well as our long collaboration with the structural biologist dr. Novel therapeutic strategies targeting hiv integrase bmc medicine. Retroviral intasome assembly and inhibition of dna strand transfer. P 2010 retroviral intasome assembly and inhibition of.
In is a key component in this and the retroviral preintegration complex. Structural basis for retroviral intasome assembly and. The structure shows the organization of retroviral intasome, with an integrase tetramer tightly associated with a pair of viral dna. The processing reaction takes place in the cytoplasm as soon as dna synthesis is completed at the termini. Due to the importance of human immunodeficiency virus type 1 hiv1 integrase as a drug target, the biochemistry and structural aspects of retroviral dna integration have been the focus of intensive research during the past three decades. Viruses free fulltext retrovirus integrasedna structure. Jan 31, 2010 the binding of strand transfer inhibitors displaces the reactive viral dna end from the active site, disarming the viral nucleoprotein complex. In the 11 march 2010 issue of nature, peter cherepanov and colleagues from the imperial college, london, determined the crystal structure of the prototype foamy virus pfv integrase in in complex with its viral dna 1. Inhibition of human immunodeficiency virus1 integrase by. Structural basis for strandtransfer inhibitor binding to hiv.
The integrase protein of retroviruses such as hiv1 catalyses insertion of the viral genome into that of the host. The structure shows the organization of retroviral intasome, with an integrase tetramer tightly associated with a pair of viral dna ends. Retroviral intasome assembly and inhibition of dna strand transfer stephen hare 1, saumya shree gupta 1,, eugene valkov 1, alan engelman 2, and peter. The development of hiv integrase in strand transfer inhibitors. Jun 29, 2012 strand transfer inhibitor binding to the retroviral intasome that has undergone 3. Structural basis of mos1 transposase inhibition by the anti. These findings define the structural basis of retroviral dna integration, and will allow modeling of the hiv1 intasome to. Before chromatography, 500 mm nacl was added to the asse. Integrase is an essential retroviral enzyme that binds both termini of linear viral dna and inserts them into a host cell chromosome. The hiv intasome is a large nucleoprotein assembly that mediates the integration of a dna copy of the viral genome into host chromatin. Our findings define the structural basis of retroviral dna integration, and will allow modelling of the hiv1 intasome to aid in the development of antiretroviral drugs.
We recently reported cocrystal structures of the prototype foamy virus pfv intasome with raltegravir and elvitegravir, establishing the general insti binding mode. In the next step, dna strand transfer, a pair of transesterification reactions2 inserts the viral dna ends into a target dna. In the 11 march 2010 issue of nature, peter cherepanov and colleagues from the imperial college, london, determined the crystal structure of the prototype foamy virus. Structural basis for strandtransfer inhibitor binding to hiv intasomes. Strand transfer inhibitors work by preventing the concerted integration of the viral dna into the host chromosome. Figure 2 retroviral integrase domain organization and hiv1 integrase domain structures. Outer domains of integrase within retroviral intasomes are. Figure 2 from retroviral integrase structure and dna. In the case of hiv1, the sites of insertion on each strand of target dna are staggered by five nucleotides. Aug 20, 2020 hiv1 integrase is the enzyme responsible for integrating the viral dna into the host genome and is one of the main targets for antiretroviral therapy.
Frontiers inhibition of htlv1 infection by hiv1 first. Structureguided optimization of hiv integrase strand. A supramolecular assembly mediates lentiviral dna integration. Pdf retroviral intasome assembly and inhibition of dna. Hivsiv intasome structures shed new light on integrase inhibitor. The mvv intasome was assembled using wild type integrase proteins and. Reactions at the retroviral dna ends produced by rt in infected cells. Molecular mechanisms of retroviral integrase inhibition and. Sep 01, 2020 integrase in strand transfer inhibitors instis are recent compounds in the antiretroviral arsenal used against hiv. Retroviral replication proceeds through an obligate proviral or integrated dna recombination intermediate. Aug, 2019 retroviral intasome assembly and inhibition of dna strand transfer. The availability of the state of the art cryoem facility at washington university in st.
Oh groups during strand transfer to cut chromosomal target dna, which simultaneously joins both viral dna ends to target dna 5. Integrase inhibitors are emerging antihuman immunodeficiency virus hiv drugs, and multiple. Structural insights into the retroviral dna integration. Both 3 end processing and dna strand transfer are carried out by viral integrase protein. At this point, the integrase forms a complex with the viral dna, creating the preintegration complex intasome. Retrovirus integrasedna structure elucidates concerted. Hiv2 integrase gene polymorphism and retroviral intasome assembly and inhibition of dna strand transfer. Funding acknowledgement medical research council, uk and national institutes of health, usa. Integrase in strand transfer inhibitors instis are recent compounds in the antiretroviral arsenal used against hiv. Retroviral intasome assembly and inhibition of dna strand transfer stephen hare1, saumya shree gupta1,, eugene valkov1, alan engelman2, and peter cherepanov1 1 division of medicine. Our findings define the structural basis of retroviral dna integration, and will allow modelling of the hiv1 intasome to.
A the nterminal domain ntd, catalytic core domain ccd, and cterminal domain ctd are common among all retroviral integrase proteins, whereas sequence analysis indicates that gammaretrovirus and epsilonretrovirus in addition to spumavirus proteins harbor an nterminal extension domain ned 55. Architecture and assembly of hiv integrase multimers in the. Engagement of target dna by the pfv intasome 12735 4. These findings define the structural basis of retroviral dna integration, and will allow modeling of the hiv1 intasome to aid in the development of antiretroviral drugs. The first retroviral intasome to be characterized structur.
A the nterminal domain ntd, catalytic core domain ccd, and cterminal domain ctd are common among all retroviral integrase proteins, whereas sequence analysis indicates that gammaretrovirus and epsilonretrovirus in addition to spumavirus proteins harbor an nterminal extension domain ned 55, 94. A cterminal tail region in the rous sarcoma virus integrase. Commentary integrating the hiv1 assemblymaturation. The ui mn structure provides an obvious explanation for the pronounced selectivity of this class of small molecules towards inhibiting strand. Pdf integrase strand transfer inhibitors as potential.
Nih public access eugene valkov alan engelman, and peter. Retroviral integration is mediated by in multimers that are assembled on the viral dna ends, forming a stable synaptic complex, also referred to as the intasome. Feb 14, 2020, retroviral intasome assembly and inhibition of dna strand transfer. Hare s, gupta ss, valkov e, engelman a, cherepanov p. Nature phenotypic susceptibility of hiv2 clinical isolates to the integrase inhib 464. Retroviral intasome assembly and inhibition of dna strand transfer the structure was solved of fulllength retroviral integrase from prototype foamy virus in complex with its cognate dna. Pdb 3l2r structure summary protein data bank in europe. Processing and strand transfer catalysed by retroviral. Binding of strand transfer inhibitors displaces the reactive viral dna end from the active site, disarming the viral nucleoprotein complex. Retroviral intasome assembly and inhibition of dna strand transfer, nature, 464, 232236 2010. Molecular mechanisms of retroviral integrase inhibition.
Later crystallization efforts by the same group yielded indna strand transfer complexes in the presence and absence of inhibitors 86, again. The macromolecular complex of an in macromolecule bound to the ends of the viral dna ends has been referred to as the intasome. The binding of strand transfer inhibitors displaces the reactive viral dna end from the active site, disarming the viral nucleoprotein complex. While the gene order of retroviruses is conserved, the synthesis of retroviral proteins can be controlled by different mechanisms. Variations include the ways in which rna splicing is used to produce mrnas from a single long transcript, a portion of which must remain unspliced to serve as the. Pdf integrase strand transfer inhibitors as potential anti. Mar 14, 2021 the intasome showed significant conformational flexibility in its overall architecture as well as the interactions of an hiv1 in strand transfer inhibitor insti in the active site. Nov 16, 2010 the development of hiv integrase in strand transfer inhibitors instis and our understanding of viral resistance to these molecules have been hampered by a paucity of available structural data. Structural basis of mos1 transposase inhibition by the. Retroviral intasome assembly and inhibition of dna strand. Recent structures of lentiviral intasomes from simian immunodeficiency virus siv.
A schematic of in dna complexes observed in in vitro systems. Differential sensitivities of retroviruses to integrase strand transfer. Jan 31, 2010 binding of strand transfer inhibitors displaces the reactive viral dna end from the active site, disarming the viral nucleoprotein complex. Retroviral ins are not to be confused with phage integrases recombinases, such as. Insti obstruction of tdna positioning for strand transfer. Crystal structures of the intasome, target capture and strand transfer complexes. In the 11 march 2010 issue of nature, peter cherepanov and colleagues from the imperial college, london, determined the crystal structure of the prototype foamy virus pfv.
Regression qsar models for predicting hiv1 integrase inhibitors. Pdf differential sensitivities of retroviruses to integrase. The structure was solved of fulllength retroviral integrase from prototype foamy virus in complex with its cognate dna. Cryoem structural studies of avian retrovirus intasomes.
The ledgf also stimulates hiv1 in dna strand transfer activity and improves its. The common antiretroviral generation potential molecule sgsk49572 3 min et. Following nuclear entry the two processed viral dna ends are joined to host dna in concerted cleavage and ligation reactions at staggered positions in the target. A peptide derived from lens epitheliumderived growth factor. After viral entry into the host cell, the reverse transcriptase converts the viral ssrna into dsdna. Our findings define the structural basis of retroviral dna integration and will allow modeling of the hiv1 intasome to aid in the development of antiretroviral drugs.
627 576 1049 1617 865 1871 1157 981 997 788 1527 1156 1129 368 1740 1339 763 480 245 1567 928 1620 1176 1494