1.95 angstrom crystal structure of TAGRFP-T

  • Classification: FLUORESCENT PROTEIN
  • Organism(s): synthetic construct
  • Mutation(s): No 

  • Deposited: 2016-05-11 Released: 2017-05-17 
  • Deposition Author(s): Hu, X.J.
  • Funding Organization(s): the National Natural Science Foundation of China,

Experimental Data Snapshot

  • Resolution: 1.95 Å
  • R-Value Free: 0.230 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.184 

wwPDB Validation   3D Report Full Report

This is version 1.3 of the entry. See complete history


The crystal structure of red fluorescent protein TagRFP-T reveals the mechanism of its superior photostability.

Liu, R.Liang, Q.N.Du, S.Q.Hu, X.J.Ding, Y.

(2016) Biochem Biophys Res Commun 477: 229-234

  • DOI: https://doi.org/10.1016/j.bbrc.2016.06.047
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    The red fluorescent protein variant TagRFP-T has greatly improved photostability over its parent molecule, TagRFP, but the underlying mechanism leading to this improvement is to date unknown. The 1.95 Å resolution crystallographic structure of TagRFP-T showed that its chromophore exists as a mixture of cis and trans coplanar isomers in roughly equal proportions. Interestingly, both isomers are able to fluoresce, a property that has never been observed in any other fluorescent protein. We propose a "circular restoration model" for TagRFP-T to explain its superior photostability: There are four co-existing chromophore states (cis/trans protonated/ionized state) that can be driven by light to transform from one state into another. This model also explains how TagRPF-T essentially eliminates the temporary dark state (reversible photobleaching).

  • Organizational Affiliation

    Department of Physiology and Biophysics, School of Life Sciences, Fudan University, Shanghai 200438, China.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
A, B, C, D
238synthetic constructMutation(s): 0 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 1.95 Å
  • R-Value Free: 0.230 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.184 
  • Space Group: I 41
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 162.21α = 90
b = 162.21β = 90
c = 76.15γ = 90
Software Package:
Software NamePurpose
HKL-2000data reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report

Entry History & Funding Information

Deposition Data

  • Released Date: 2017-05-17 
  • Deposition Author(s): Hu, X.J.
  • This entry supersedes: 3T6H

Funding OrganizationLocationGrant Number
the National Natural Science Foundation of China,China31470764

Revision History  (Full details and data files)

  • Version 1.0: 2017-05-17
    Type: Initial release
  • Version 1.1: 2023-11-08
    Changes: Data collection, Database references, Refinement description
  • Version 1.2: 2023-11-15
    Changes: Data collection
  • Version 1.3: 2024-04-03
    Changes: Derived calculations