6U32 image
Entry Detail
PDB ID:
6U32
Keywords:
Title:
Crystal structure of HaloTag bound to tetramethylrhodamine-HaloTag ligand
Biological Source:
Source Organism:
Host Organism:
PDB Version:
Deposition Date:
2019-08-21
Release Date:
2020-09-30
Method Details:
Experimental Method:
Resolution:
1.80 Å
R-Value Free:
0.19
R-Value Work:
0.15
R-Value Observed:
0.15
Space Group:
P 43 21 2
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:HaloTag
Chain IDs:A
Chain Length:297
Number of Molecules:1
Biological Source:Rhodococcus sp.
Primary Citation
The HaloTag as a general scaffold for far-red tunable chemigenetic indicators.
Nat.Chem.Biol. 17 718 723 (2021)
PMID: 33795886 DOI: 10.1038/s41589-021-00775-w

Abstact

Functional imaging using fluorescent indicators has revolutionized biology, but additional sensor scaffolds are needed to access properties such as bright, far-red emission. Here, we introduce a new platform for 'chemigenetic' fluorescent indicators, utilizing the self-labeling HaloTag protein conjugated to environmentally sensitive synthetic fluorophores. We solve a crystal structure of HaloTag bound to a rhodamine dye ligand to guide engineering efforts to modulate the dye environment. We show that fusion of HaloTag with protein sensor domains that undergo conformational changes near the bound dye results in large and rapid changes in fluorescence output. This generalizable approach affords bright, far-red calcium and voltage sensors with highly tunable photophysical and chemical properties, which can reliably detect single action potentials in cultured neurons.

Legend

Protein

Chemical

Disease

Primary Citation of related structures