7U32

MVV cleaved synaptic complex (CSC) intasome at 3.4 A resolution

Summary for 7U32

• Entry DOI: 10.2210/pdb7u32/pdb
• EMDB information: 14453 26322
• Descriptor: Integrase, DNA EV273, DNA EV272, ... (5 entities in total)
• Functional Keywords: integrase-dna complex, hydrolase, viral protein, viral protein-dna complex, viral protein/dna
• Biological source: Visna/maedi virus EV1 KV1772; More
• Total number of polymer chains: 20
• Total formula weight: 553198.37

Authors

Shan, Z.,Pye, V.E.,Cherepanov, P.,Lyumkis, D. (deposition date: 2022-02-25, release date: 2022-05-11, Last modification date: 2025-05-28)

Primary citation

Ballandras-Colas, A.,Chivukula, V.,Gruszka, D.T.,Shan, Z.,Singh, P.K.,Pye, V.E.,McLean, R.K.,Bedwell, G.J.,Li, W.,Nans, A.,Cook, N.J.,Fadel, H.J.,Poeschla, E.M.,Griffiths, D.J.,Vargas, J.,Taylor, I.A.,Lyumkis, D.,Yardimci, H.,Engelman, A.N.,Cherepanov, P.
Multivalent interactions essential for lentiviral integrase function.
Nat Commun, 13:2416-2416, 2022

PubMed Abstract: A multimer of retroviral integrase (IN) synapses viral DNA ends within a stable intasome nucleoprotein complex for integration into a host cell genome. Reconstitution of the intasome from the maedi-visna virus (MVV), an ovine lentivirus, revealed a large assembly containing sixteen IN subunits. Herein, we report cryo-EM structures of the lentiviral intasome prior to engagement of target DNA and following strand transfer, refined at 3.4 and 3.5 Å resolution, respectively. The structures elucidate details of the protein-protein and protein-DNA interfaces involved in lentiviral intasome formation. We show that the homomeric interfaces involved in IN hexadecamer formation and the α-helical configuration of the linker connecting the C-terminal and catalytic core domains are critical for MVV IN strand transfer activity in vitro and for virus infectivity. Single-molecule microscopy in conjunction with photobleaching reveals that the MVV intasome can bind a variable number, up to sixteen molecules, of the lentivirus-specific host factor LEDGF/p75. Concordantly, ablation of endogenous LEDGF/p75 results in gross redistribution of MVV integration sites in human and ovine cells. Our data confirm the importance of the expanded architecture observed in cryo-EM studies of lentiviral intasomes and suggest that this organization underlies multivalent interactions with chromatin for integration targeting to active genes.

PubMed: 35504909
DOI: 10.1038/s41467-022-29928-8

Experimental method

ELECTRON MICROSCOPY (3.46 Å)