8ILS

Cryo-EM structure of PI3Kalpha in complex with compound 17


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.10 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 1.0 of the entry. See complete history


Literature

Structural insights into the interaction of three Y-shaped ligands with PI3K alpha.

Zhou, Q.Liu, X.Neri, D.Li, W.Favalli, N.Bassi, G.Yang, S.Yang, D.Vogt, P.K.Wang, M.W.

(2023) Proc Natl Acad Sci U S A 120: e2304071120-e2304071120

  • DOI: https://doi.org/10.1073/pnas.2304071120
  • Primary Citation of Related Structures:  
    8ILR, 8ILS, 8ILV

  • PubMed Abstract: 

    Class IA phosphoinositide 3-kinase alpha (PI3Kα) is an important drug target because it is one of the most frequently mutated proteins in human cancers. However, small molecule inhibitors currently on the market or under development have safety concerns due to a lack of selectivity. Therefore, other chemical scaffolds or unique mechanisms of catalytic kinase inhibition are needed. Here, we report the cryo-electron microscopy structures of wild-type PI3Kα, the dimer of p110α and p85α, in complex with three Y-shaped ligands [cpd16 (compound 16), cpd17 (compound 17), and cpd18 (compound 18)] of different affinities and no inhibitory effect on the kinase activity. Unlike ATP-competitive inhibitors, cpd17 adopts a Y-shaped conformation with one arm inserted into a binding pocket formed by R770 and W780 and the other arm lodged in the ATP-binding pocket at an angle that is different from that of the ATP phosphate tail. Such a special interaction induces a conformation of PI3Kα resembling that of the unliganded protein. These observations were confirmed with two isomers (cpd16 and cpd18). Further analysis of these Y-shaped ligands revealed the structural basis of differential binding affinities caused by stereo- or regiochemical modifications. Our results may offer a different direction toward the design of therapeutic agents against PI3Kα.


  • Organizational Affiliation

    The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit alpha isoform1,096Homo sapiensMutation(s): 0 
Gene Names: PIK3CA
EC: 2.7.1.137 (PDB Primary Data), 2.7.1.153 (PDB Primary Data), 2.7.11.1 (PDB Primary Data)
UniProt & NIH Common Fund Data Resources
Find proteins for P42336 (Homo sapiens)
Explore P42336 
Go to UniProtKB:  P42336
GTEx:  ENSG00000121879 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP42336
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Phosphatidylinositol 3-kinase regulatory subunit alpha723Homo sapiensMutation(s): 0 
Gene Names: PIK3R1GRB1
UniProt & NIH Common Fund Data Resources
Find proteins for P27986 (Homo sapiens)
Explore P27986 
Go to UniProtKB:  P27986
GTEx:  ENSG00000145675 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP27986
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
7U5
Query on 7U5

Download Ideal Coordinates CCD File 
C [auth A]N-[(2R)-1-(ethylamino)-1-oxidanylidene-3-[4-(2-quinoxalin-6-ylethynyl)phenyl]propan-2-yl]-2,3-dimethyl-quinoxaline-6-carboxamide
C32 H28 N6 O2
NWRUSGJCZMKYKB-SSEXGKCCSA-N
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.10 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 
EM Software:
TaskSoftware PackageVersion
MODEL REFINEMENTPHENIX1.18.2-3874

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Natural Science Foundation of China (NSFC)China81872915
National Natural Science Foundation of China (NSFC)China82073904
National Natural Science Foundation of China (NSFC)China82121005
National Natural Science Foundation of China (NSFC)China81973373
National Natural Science Foundation of China (NSFC)China21704064
Other government2018ZX09735-001
Other government2018ZX09711002-002-005
Other government2021ZD0203400
Other government2018YFA0507000
Other governmentZDKJ2021028
Other governmentNNCAS-2017-1-CC
National Institutes of Health/Eunice Kennedy Shriver National Institute of Child Health & Human Development (NIH/NICHD)United StatesR35 CA197582

Revision History  (Full details and data files)

  • Version 1.0: 2023-09-13
    Type: Initial release