6TZ4

CryoEM reconstruction of membrane-bound ESCRT-III filament composed of CHMP1B+IST1 (right-handed)

  • Classification: LIPID BINDING PROTEIN
  • Organism(s): Homo sapiens
  • Expression System: Escherichia coli
  • Mutation(s): Yes 
  • Membrane Protein: Yes  mpstruc

  • Deposited: 2019-08-10 Released: 2020-04-08 
  • Deposition Author(s): Nguyen, H.C., Frost, A.
  • Funding Organization(s): National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID), National Institutes of Health/Office of the Director, National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)

Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.20 Å
  • Aggregation State: HELICAL ARRAY 
  • Reconstruction Method: HELICAL 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Membrane constriction and thinning by sequential ESCRT-III polymerization.

Nguyen, H.C.Talledge, N.McCullough, J.Sharma, A.Moss 3rd, F.R.Iwasa, J.H.Vershinin, M.D.Sundquist, W.I.Frost, A.

(2020) Nat Struct Mol Biol 27: 392-399

  • DOI: https://doi.org/10.1038/s41594-020-0404-x
  • Primary Citation of Related Structures:  
    6TZ4, 6TZ5, 6TZ9, 6TZA

  • PubMed Abstract: 

    The endosomal sorting complexes required for transport (ESCRTs) mediate diverse membrane remodeling events. These typically require ESCRT-III proteins to stabilize negatively curved membranes; however, recent work has indicated that certain ESCRT-IIIs also participate in positive-curvature membrane-shaping reactions. ESCRT-IIIs polymerize into membrane-binding filaments, but the structural basis for negative versus positive membrane remodeling by these proteins remains poorly understood. To learn how certain ESCRT-IIIs shape positively curved membranes, we determined structures of human membrane-bound CHMP1B-only, membrane-bound CHMP1B + IST1, and IST1-only filaments by cryo-EM. Our structures show how CHMP1B first polymerizes into a single-stranded helical filament, shaping membranes into moderate-curvature tubules. Subsequently, IST1 assembles a second strand on CHMP1B, further constricting the membrane tube and reducing its diameter nearly to the fission point. Each step of constriction thins the underlying bilayer, lowering the barrier to membrane fission. Our structures reveal how a two-component, sequential polymerization mechanism drives membrane tubulation, constriction and bilayer thinning.


  • Organizational Affiliation

    Department of Biochemistry & Biophysics, University of California, San Francisco, San Francisco, CA, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Charged multivesicular body protein 1b199Homo sapiensMutation(s): 1 
Gene Names: CHMP1BC18orf2
Membrane Entity: Yes 
UniProt & NIH Common Fund Data Resources
Find proteins for Q7LBR1 (Homo sapiens)
Explore Q7LBR1 
Go to UniProtKB:  Q7LBR1
PHAROS:  Q7LBR1
GTEx:  ENSG00000255112 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ7LBR1
Sequence Annotations
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
IST1 homolog189Homo sapiensMutation(s): 0 
Gene Names: IST1KIAA0174
UniProt & NIH Common Fund Data Resources
Find proteins for P53990 (Homo sapiens)
Explore P53990 
Go to UniProtKB:  P53990
PHAROS:  P53990
GTEx:  ENSG00000182149 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP53990
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.20 Å
  • Aggregation State: HELICAL ARRAY 
  • Reconstruction Method: HELICAL 
EM Software:
TaskSoftware PackageVersion
MODEL REFINEMENTPHENIX
RECONSTRUCTIONRELION

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)United StatesP50 AI150464
National Institutes of Health/Office of the DirectorUnited StatesS10OD020054
National Institutes of Health/Office of the DirectorUnited StatesS10OD021741
National Institutes of Health/Office of the DirectorUnited States1S10OD021596-01
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United States1DP2GM110772-01

Revision History  (Full details and data files)

  • Version 1.0: 2020-04-08
    Type: Initial release
  • Version 1.1: 2020-04-22
    Changes: Database references
  • Version 1.2: 2024-03-20
    Changes: Data collection, Database references