6WAZ

+1 extended HIV-1 reverse transcriptase initiation complex core (pre-translocation state)


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 4.10 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation 3D Report Full Report



Literature

Distinct Conformational States Underlie Pausing during Initiation of HIV-1 Reverse Transcription.

Larsen, K.P.Choi, J.Jackson, L.N.Kappel, K.Zhang, J.Ha, B.Chen, D.H.Puglisi, E.V.

(2020) J Mol Biol 

  • DOI: 10.1016/j.jmb.2020.06.003
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • A hallmark of the initiation step of HIV-1 reverse transcription, in which viral RNA genome is converted into double-stranded DNA, is that it is slow and non-processive. Biochemical studies have identified specific sites along the viral RNA genomic t ...

    A hallmark of the initiation step of HIV-1 reverse transcription, in which viral RNA genome is converted into double-stranded DNA, is that it is slow and non-processive. Biochemical studies have identified specific sites along the viral RNA genomic template in which reverse transcriptase (RT) stalls. These stalling points, which occur after the addition of 3 and 5 template dNTPs, may serve as checkpoints to regulate the precise timing of HIV-1 reverse transcription following viral entry. Structural studies of reverse transcriptase initiation complexes (RTICs) have revealed unique conformations that may explain the slow rate of incorporation, however, questions remain about the temporal evolution of the complex and features that contribute to strong pausing during initiation. Here we present cryo-electron microscopy (cryo-EM) and single-molecule characterization of an RTIC after three rounds of dNTP incorporation (+3), the first major pausing point during reverse transcription initiation. Cryo-EM structures of a + 3 extended RTIC reveal conformational heterogeneity within the RTIC core. Three distinct conformations were identified, two of which adopt unique, likely off-pathway, intermediates in the canonical polymerization cycle. Single-molecule Förster resonance energy transfer (smFRET) experiments confirm that the +3 RTIC is more structurally dynamic than earlier stage RTICs. These alternative conformations were selectively disrupted through structure-guided point mutations to shift smFRET populations back towards the on-pathway conformation. Our results support the hypothesis that conformational heterogeneity within the HIV-1 reverse transcriptase initiation complex during pausing serves as an additional means of regulating HIV-1 replication.


    Organizational Affiliation

    Department of Structural Biology, Stanford University School of Medicine, Stanford, CA, USA. Electronic address: epuglisi@stanford.edu.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Reverse transcriptase/ribonuclease H
A
562Human immunodeficiency virus type 1 BH10Mutation(s): 2 
Gene Names: gag-pol
EC: 2.7.7.49 (PDB Primary Data), 2.7.7.7 (PDB Primary Data), 3.1.26.13 (PDB Primary Data), 3.4.23.16 (UniProt), 3.1.13.2 (UniProt), 2.7.7 (UniProt), 3.1 (UniProt)
Find proteins for P03366 (Human immunodeficiency virus type 1 group M subtype B (isolate BH10))
Go to UniProtKB:  P03366
Protein Feature View
  • Reference Sequence

Find similar proteins by: Sequence  |  Structure

Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Reverse transcriptase p51 subunit
B
442Human immunodeficiency virus 1Mutation(s): 1 
EC: 3.4.23.16 (UniProt), 2.7.7.49 (UniProt), 2.7.7.7 (UniProt), 3.1.26.13 (UniProt), 3.1.13.2 (UniProt), 2.7.7 (UniProt), 3.1 (UniProt)
Find proteins for P03366 (Human immunodeficiency virus type 1 group M subtype B (isolate BH10))
Go to UniProtKB:  P03366
Protein Feature View
  • Reference Sequence

Find similar nucleic acids by: Sequence   |  Structure

Entity ID: 3
MoleculeChainsLengthOrganism
HIV-1 viral RNA genome fragmentC101Human immunodeficiency virus 1

Find similar nucleic acids by:   |  Structure

Entity ID: 4
MoleculeChainsLengthOrganism
tRNA lysine 3D77Homo sapiens
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 4.10 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesGM082545

Revision History 

  • Version 1.0: 2020-06-24
    Type: Initial release