Intracellular fluorescence competition assay for inhibitor engagement of histone deacetylase



An intracellular fluorescence competition assay was developed to assess the capability of inhibitor candidates to engage histone deacetylase (HDAC) inside living cells and thus diminish cell uptake and staining by the HDACtargeted fluorescent probe APS. Fluorescence cell microscopy and flow cytometry showed that pre-incubation of living cells with candidate inhibitors led to diminished cell uptake of the fluorescent probe. The assay was effective because the fluorescent probe (APS) possessed the required performance properties, including bright fluorescence, ready membrane diffusion, selective intracellular HDAC affinity, and negligible acute cytotoxicity. The concept of an intracellular fluorescence competition assay is generalizable and has broad applicability since it obviates the requirement to use the isolated biomacromolecule target for screening of molecular candidates with target affinity.


Attribute NameValues
  • Elley Rudebeck

  • Bradley D. Smith

  • Frederick M. Pfeffer

Journal or Work Title
  • Bioorganic & Medicinal Chemistry Letters

  • 47

First Page
  • 128207

Publication Date
  • 2021-09

  • AMI HD Imaging

  • IVIS Lumina

  • Naphthalimide

  • Histone deacetylase

  • Inhibitor

  • Scriptaid

  • Fluorescence cell microscopy

  • Fluorescent molecular probe

  • Elsevier

Date Created
  • 2022-11-18

Bibliographic Citation
  • English

Departments and Units
Record Visibility Public
Content License
  • All rights reserved

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