1IAS

CYTOPLASMIC DOMAIN OF UNPHOSPHORYLATED TYPE I TGF-BETA RECEPTOR CRYSTALLIZED WITHOUT FKBP12

• PDB DOI: https://doi.org/10.2210/pdb1IAS/pdb

• Classification: TRANSFERASE
• Organism(s): Homo sapiens
• Expression System: Spodoptera frugiperda
• Mutation(s): No 


• Deposited: 2001-03-23 Released: 2001-10-03 
• Deposition Author(s): Huse, M., Muir, T.W., Chen, Y.-G., Kuriyan, J., Massague, J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.284 
• R-Value Work: 0.255 
• R-Value Observed: 0.255 

Starting Model: experimental

Literature

The TGF beta receptor activation process: an inhibitor- to substrate-binding switch.

Huse, M., Muir, T.W., Xu, L., Chen, Y.G., Kuriyan, J., Massague, J.

(2001) Mol Cell 8: 671-682

• PubMed: 11583628 
• DOI: https://doi.org/10.1016/s1097-2765(01)00332-x
• Primary Citation of Related Structures:  
  1IAS


• PubMed Abstract: 
  

  The type I TGF beta receptor (T beta R-I) is activated by phosphorylation of the GS region, a conserved juxtamembrane segment located just N-terminal to the kinase domain. We have studied the molecular mechanism of receptor activation using a homogeneously tetraphosphorylated form of T beta R-I, prepared using protein semisynthesis. Phosphorylation of the GS region dramatically enhances the specificity of T beta R-I for the critical C-terminal serines of Smad2. In addition, tetraphosphorylated T beta R-I is bound specifically by Smad2 in a phosphorylation-dependent manner and is no longer recognized by the inhibitory protein FKBP12. Thus, phosphorylation activates T beta R-I by switching the GS region from a binding site for an inhibitor into a binding surface for substrate. Our observations suggest that phosphoserine/phosphothreonine-dependent localization is a key feature of the T beta R-I/Smad activation process.

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Organizational Affiliation: 

Laboratory of Molecular Biophysics, Rockefeller University, New York, NY 10021, USA.

Biological Assembly 1  

Global Symmetry: Cyclic - C5  (Explore in 3D)
Global Stoichiometry: Homo 5-mer - A5 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 196.04 kDa 
• Atom Count: 13,181 
• Modelled Residue Count: 1,644 
• Deposited Residue Count: 1,710 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
TGF-BETA RECEPTOR TYPE I	A, B, C, D, E	342	Homo sapiens	Mutation(s): 0  EC: 2.7.1.37 (PDB Primary Data), 2.7.11.30 (UniProt)
UniProt & NIH Common Fund Data Resources
Find proteins for P36897 (Homo sapiens) Explore P36897  Go to UniProtKB:  P36897
PHAROS:  P36897 GTEx:  ENSG00000106799

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SO4	F [auth A], G [auth A], H [auth A], I [auth B], J [auth B], K [auth B], L [auth C], M [auth C], N [auth C], O [auth D], P [auth D], Q [auth D], R [auth E], S [auth E], T [auth E]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.90 Å
• R-Value Free: 0.284 
• R-Value Work: 0.255 
• R-Value Observed: 0.255 
• Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 172.56	α = 90
b = 251.617	β = 90
c = 140.228	γ = 90

Software Package:

Software Name	Purpose
AMoRE	phasing
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2001-10-03 
Deposition Author(s): Huse, M., Muir, T.W., Chen, Y.-G., Kuriyan, J., Massague, J.

Revision History  

• Version 1.0: 2001-10-03
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2024-02-07
  Changes: Data collection, Database references, Derived calculations
• Version 1.4: 2024-04-03
  Changes: Refinement description