30YJ | pdb_000030yj

Ternary structure of 14-3-3sigma, interaction cassette phosphopeptide 2, and Fusicoccin-A.

• PDB DOI: https://doi.org/10.2210/pdb30YJ/pdb

• Classification: PEPTIDE BINDING PROTEIN
• Organism(s): Homo sapiens, synthetic construct
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2026-05-18 Released: 2026-09-02 
• Deposition Author(s): Ni, Y., Brusveld, L., Ottmann, C., Munoz Lasso, D.
• Funding Organization(s): Other private

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.50 Å
• R-Value Free: 
  0.185 (Depositor), 0.184 (DCC) 
• R-Value Work: 
  0.135 (Depositor), 0.136 (DCC) 
• R-Value Observed: 
  0.137 (Depositor) 

Starting Model: experimental

Literature

Molecular Glue and Phosphorylation-Dependent 14-3-3 Recruitment to p53 with an Engineered Interaction Cassette.

Munoz-Lasso, D.C., Ni, Y., Weber, G., Eduati, F., Beijersbergen, R.L., Ottmann, C., Brunsveld, L.

(2026) ACS Chem Biol 

• PubMed: 42631642 
• DOI: https://doi.org/10.1021/acschembio.6c00482
• Primary Citation Related Structures: 
  28UW, 30YJ, 30ZW, 30ZX


• PubMed Abstract: 
  

  The tumor suppressor p53 is regulated by phosphorylation-dependent protein-protein interactions, including via binding to 14-3-3 adaptor proteins, which can tune p53 activity. Molecular glue (MG)-induced stabilization of 14-3-3/client interactions offers an attractive strategy to probe such networks, but cellular engagement is often constrained by context-dependent phosphorylation and interaction occupancy. Here, we engineered phosphorylation- and MG-dependent 14-3-3 interaction cassettes (IC1 and IC2) and fused them to p53 to promote recruitment of endogenous 14-3-3 proteins in human cells. Biochemical characterization establishes high-affinity binding of the phosphorylated cassettes to 14-3-3 and enhanced in vitro stabilization by the 14-3-3 molecular glue 3'-deacetylated fusicoccin-A (FC-A). In HEK293T cells, Flag-p53-IC1 and Flag-p53-IC2 co-immunoprecipitated native 14-3-3 proteins. Mutation of the cassette's phospho-accepting serine to alanine abolished binding, confirming phosphorylation dependent recruitment. Transcriptomic profiling of transiently transfected cells reveals cassette-dependent remodeling of a p53-associated gene expression landscape. Together, these results establish a modular, MG- and phosphorylation-dependent platform for engaging 14-3-3 in a p53 context and for evaluating how chemical stabilization translates from biochemical interaction control to cellular pathway-level readouts.

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Organizational Affiliation: 
• Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, 5600MBEindhoven, The Netherlands.
Computational Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, 5600MBEindhoven, The Netherlands.
Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, 1066CXAmsterdam, The Netherlands.
Ambagon Therapeutics, 5612AREindhoven, The Netherlands.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Hetero 4-mer - A2B2 Pseudo Symmetry: Asymmetric - C1 
Pseudo Stoichiometry: Hetero 4-mer - A2B1C1 

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

Macromolecule Content 

• Total Structure Weight: 28.92 kDa 
• Atom Count: 2,400 
• Modeled Residue Count: 242 
• Deposited Residue Count: 249 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
14-3-3 protein sigma	A	236	Homo sapiens	Mutation(s): 0  Gene Names: SFN, HME1
UniProt & NIH Common Fund Data Resources
Find proteins for P31947 (Homo sapiens) Explore P31947  Go to UniProtKB:  P31947
PHAROS:  P31947 GTEx:  ENSG00000175793

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
interaction cassette peptide 2	B [auth P]	13	synthetic construct	Mutation(s): 0

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SIT (Subject of Investigation/LOI)	G [auth A]	De-acetylated Fusicoccin C34 H54 O11 IEYDDQSCFAJEQD-AHQPFIERSA-N
CL	D [auth A]	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M
MG	C [auth A], E [auth A], F [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Modified Residues  2 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
CSO	A	L-PEPTIDE LINKING	C3 H7 N O3 S		CYS
SEP	B [auth P]	L-PEPTIDE LINKING	C3 H8 N O6 P		SER

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.50 Å
• R-Value Free:  0.185 (Depositor), 0.184 (DCC) 
• R-Value Work:  0.135 (Depositor), 0.136 (DCC) 
• R-Value Observed: 0.137 (Depositor) 

Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 82.156	α = 90
b = 111.414	β = 90
c = 62.63	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
Aimless	data scaling
MOLREP	phasing
DIALS	data collection

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2026-09-02 
Deposition Author(s): Ni, Y., Brusveld, L., Ottmann, C., Munoz Lasso, D.

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Funding Organization	Location	Grant Number
Other private	Netherlands	--

Revision History  

• Version 1.0: 2026-09-02
  Type: Initial release