5UKG

Crystal Structure of the genetically encoded calcium indicator K-GECO


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.36 Å
  • R-Value Free: 0.275 
  • R-Value Work: 0.206 
  • R-Value Observed: 0.210 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

A genetically encoded Ca2+indicator based on circularly permutated sea anemone red fluorescent protein eqFP578.

Shen, Y.Dana, H.Abdelfattah, A.S.Patel, R.Shea, J.Molina, R.S.Rawal, B.Rancic, V.Chang, Y.F.Wu, L.Chen, Y.Qian, Y.Wiens, M.D.Hambleton, N.Ballanyi, K.Hughes, T.E.Drobizhev, M.Kim, D.S.Koyama, M.Schreiter, E.R.Campbell, R.E.

(2018) BMC Biol 16: 9-9

  • DOI: https://doi.org/10.1186/s12915-018-0480-0
  • Primary Citation of Related Structures:  
    5UKG

  • PubMed Abstract: 

    Genetically encoded calcium ion (Ca 2+ ) indicators (GECIs) are indispensable tools for measuring Ca 2+ dynamics and neuronal activities in vitro and in vivo. Red fluorescent protein (RFP)-based GECIs have inherent advantages relative to green fluorescent protein-based GECIs due to the longer wavelength light used for excitation. Longer wavelength light is associated with decreased phototoxicity and deeper penetration through tissue. Red GECI can also enable multicolor visualization with blue- or cyan-excitable fluorophores. Here we report the development, structure, and validation of a new RFP-based GECI, K-GECO1, based on a circularly permutated RFP derived from the sea anemone Entacmaea quadricolor. We have characterized the performance of K-GECO1 in cultured HeLa cells, dissociated neurons, stem-cell-derived cardiomyocytes, organotypic brain slices, zebrafish spinal cord in vivo, and mouse brain in vivo. K-GECO1 is the archetype of a new lineage of GECIs based on the RFP eqFP578 scaffold. It offers high sensitivity and fast kinetics, similar or better than those of current state-of-the-art indicators, with diminished lysosomal accumulation and minimal blue-light photoactivation. Further refinements of the K-GECO1 lineage could lead to further improved variants with overall performance that exceeds that of the most highly optimized red GECIs.


  • Organizational Affiliation

    Department of Chemistry, University of Alberta, Edmonton, Alberta, T6G 2G2, Canada.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
K-GECO
A, B
417Entacmaea quadricolorMutation(s): 0 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.36 Å
  • R-Value Free: 0.275 
  • R-Value Work: 0.206 
  • R-Value Observed: 0.210 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 42.284α = 90
b = 129.249β = 106.27
c = 78.715γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
HKL-2000data reduction
HKL-2000data scaling
PHASERphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2018-02-07
    Type: Initial release
  • Version 1.1: 2019-02-20
    Changes: Data collection, Database references