Premium
A Fluorogenic Proteostasis Sensor to Monitor Proteome Stress in Real‐Time
Author(s) -
Zhang Xin,
Liu Yu
Publication year - 2017
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.31.1_supplement.118.1
Subject(s) - proteostasis , proteome , human proteome project , protein aggregation , microbiology and biotechnology , chemistry , protein folding , biology , proteomics , biochemistry , gene
Cellular stress can lead to global misfolding and aggregation of the endogenous proteome, resulting in a disruption of protein homeostasis (proteostasis). Monitoring proteostasis efficacy in response to stress in real time remains one of the major technical challenges facing established sensors of this process. Herein we introduce a fluorogenic proteostasis sensor based on a metastable Halo mutant in which misfolding and aggregation visually reports proteostasis deficiency. For this purpose, a solvatochromic fluorophore was designed to act as a ligand that can form a stable conjugate with Halo. The Halo•ligand conjugate maintains a fluorescent dark state when the Halo protein is folded but fluoresces strongly when the Halo•ligand conjugate misfolds and aggregates. In both E. coli and mammalian cells, we have demonstrated the utility of the sensor in monitoring proteostasis deficiency under a variety of stress conditions including environmental perturbations and incubation with a proteasome inhibitor. We show that the fluorogenic properties of this proteostasis sensor enables facile monitoring the proteome stress and allows us to discover the proteome aggregation that is induced by a series of anti‐cancer drugs. This work highlights the utility of solvatochromic fluorophores in direct visualization of protein misfolding and aggregation in live cells, providing new methodologies for real‐time analyses of cellular proteostasis upon exposure to different types of stress conditions. Support or Funding Information This work has been supported by the Burroughs Wellcome Fund Career Award at the Scientific Interface, the Paul Berg Early Career Professorship, and the Lloyd and Dottie Huck Early Career Award.