8AXW | pdb_00008axw

The structure of mouse AsterC (GramD1c) with Ezetimibe

• PDB DOI: https://doi.org/10.2210/pdb8AXW/pdb

• Classification: LIPID TRANSPORT
• Organism(s): Mus musculus
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2022-09-01 Released: 2023-09-13 
• Deposition Author(s): Fairall, L., Xiao, X., Burger, L., Tontonoz, P., Schwabe, J.W.R.
• Funding Organization(s): Leducq Foundation

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.60 Å
• R-Value Free: 
  0.206 (Depositor), 0.206 (DCC) 
• R-Value Work: 
  0.172 (Depositor), 0.172 (DCC) 
• R-Value Observed: 
  0.172 (Depositor) 

Starting Model: experimental

Literature

Aster-dependent nonvesicular transport facilitates dietary cholesterol uptake.

Ferrari, A., Whang, E., Xiao, X., Kennelly, J.P., Romartinez-Alonso, B., Mack, J.J., Weston, T., Chen, K., Kim, Y., Tol, M.J., Bideyan, L., Nguyen, A., Gao, Y., Cui, L., Bedard, A.H., Sandhu, J., Lee, S.D., Fairall, L., Williams, K.J., Song, W., Munguia, P., Russell, R.A., Martin, M.G., Jung, M.E., Jiang, H., Schwabe, J.W.R., Young, S.G., Tontonoz, P.

(2023) Science 382: eadf0966-eadf0966

• PubMed: 37943936 
• DOI: https://doi.org/10.1126/science.adf0966
• Primary Citation Related Structures: 
  8AXW


• PubMed Abstract: 
  

  Intestinal absorption is an important contributor to systemic cholesterol homeostasis. Niemann-Pick C1 Like 1 (NPC1L1) assists in the initial step of dietary cholesterol uptake, but how cholesterol moves downstream of NPC1L1 is unknown. We show that Aster-B and Aster-C are critical for nonvesicular cholesterol movement in enterocytes. Loss of NPC1L1 diminishes accessible plasma membrane (PM) cholesterol and abolishes Aster recruitment to the intestinal brush border. Enterocytes lacking Asters accumulate PM cholesterol and show endoplasmic reticulum cholesterol depletion. Aster-deficient mice have impaired cholesterol absorption and are protected against diet-induced hypercholesterolemia. Finally, the Aster pathway can be targeted with a small-molecule inhibitor to manipulate cholesterol uptake. These findings identify the Aster pathway as a physiologically important and pharmacologically tractable node in dietary lipid absorption.

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Organizational Affiliation: 
• Department of Pathology and Laboratory Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Department of Biological Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Pediatric Gastroenterology, Hepatology, and Nutrition, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Institute for Structural and Chemical Biology, University of Leicester, Leicester LE1 7RH, UK.
Department of Medicine, Division of Cardiology, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
Department of Human Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Department of Chemistry, The University of Hong Kong, Hong Kong 999077, China.
School of Molecular Sciences, The University of Western Australia, Crawley, WA 6009, Australia.
Department of Chemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine.
Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA.
UCLA Lipidomics Core, University of California, Los Angeles, Los Angeles, CA 90095, USA.
National Deuteration Facility, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2234, Australia.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content 

• Total Structure Weight: 27.18 kDa 
• Atom Count: 1,666 
• Modeled Residue Count: 171 
• Deposited Residue Count: 224 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Protein Aster-C	A	224	Mus musculus	Mutation(s): 0  Gene Names: Gramd1c
UniProt & NIH Common Fund Data Resources
Find proteins for Q8CI52 (Mus musculus) Explore Q8CI52  Go to UniProtKB:  Q8CI52
IMPC:  MGI:2443024

Small Molecules

Ligands 5 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
H56 (Subject of Investigation/LOI)	J [auth A]	(3~{R},4~{S})-1-(4-fluorophenyl)-3-[(3~{S})-3-(4-fluorophenyl)-3-oxidanyl-propyl]-4-(4-hydroxyphenyl)azetidin-2-one C24 H21 F2 N O3 OLNTVTPDXPETLC-XPWALMASSA-N
PGE	I [auth A]	TRIETHYLENE GLYCOL C6 H14 O4 ZIBGPFATKBEMQZ-UHFFFAOYSA-N
GOL	B [auth A], E [auth A]	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N
EOH	C [auth A], D [auth A], F [auth A], G [auth A]	ETHANOL C2 H6 O LFQSCWFLJHTTHZ-UHFFFAOYSA-N
CL	H [auth A]	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.60 Å
• R-Value Free:  0.206 (Depositor), 0.206 (DCC) 
• R-Value Work:  0.172 (Depositor), 0.172 (DCC) 
• R-Value Observed: 0.172 (Depositor) 

Space Group: P 4₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 49.625	α = 90
b = 49.625	β = 90
c = 144.775	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
xia2	data reduction
Aimless	data scaling
PHASER	phasing

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2023-09-13 
Deposition Author(s): Fairall, L., Xiao, X., Burger, L., Tontonoz, P., Schwabe, J.W.R.

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Funding Organization	Location	Grant Number
Leducq Foundation	France	19CVD04

Revision History  

• Version 1.0: 2023-09-13
  Type: Initial release
  
• Version 1.1: 2024-03-20
  Changes: Database references
• Version 1.2: 2026-03-04
  Changes: Refinement description, Structure summary