The small molecule '1-(4-biphenylylcarbonyl)-4-(5-bromo-2-methoxybenzyl) piperazine oxalate' and its derivatives regulate global protein synthesis by inactivating eukaryotic translation initiation factor 2-alpha

Cell Stress Chaperones. 2016 May;21(3):485-97. doi: 10.1007/s12192-016-0677-5. Epub 2016 Feb 12.


By environmental stresses, cells can initiate a signaling pathway in which eukaryotic translation initiation factor 2-alpha (eIF2-α) is involved to regulate the response. Phosphorylation of eIF2-α results in the reduction of overall protein neogenesis, which allows cells to conserve resources and to reprogram energy usage for effective stress control. To investigate the role of eIF2-α in cell stress responses, we conducted a viability-based compound screen under endoplasmic reticulum (ER) stress condition, and identified 1-(4-biphenylylcarbonyl)-4-(5-bromo-2-methoxybenzyl) piperazine oxalate (AMC-01) and its derivatives as eIF2-α-inactivating chemical. Molecular characterization of this signaling pathway revealed that AMC-01 induced inactivation of eIF2-α by phosphorylating serine residue 51 in a dose- and time-dependent manner, while the negative control compounds did not affect eIF2-α phosphorylation. In contrast with ER stress induction by thapsigargin, phosphorylation of eIF2-α persisted for the duration of incubation with AMC-01. By pathway analysis, AMC-01 clearly induced the activation of protein kinase RNA-activated (PKR) kinase and nuclear factor-κB (NF-κB), whereas it did not modulate the activity of PERK or heme-regulated inhibitor (HRI). Finally, we could detect a lower protein translation rate in cells incubated with AMC-01, establishing AMC-01 as a potent chemical probe that can regulate eIF2-α activity. We suggest from these data that AMC-01 and its derivative compounds can be used as chemical probes in future studies of the role of eIF2-α in protein synthesis-related cell physiology.

Keywords: Cell stress response; Eukaryotic translation initiation factor 2-alpha; Molecular probe.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Endoplasmic Reticulum / drug effects
  • Endoplasmic Reticulum / genetics
  • Endoplasmic Reticulum Stress / drug effects
  • Endoplasmic Reticulum Stress / genetics*
  • Gene Expression Regulation / drug effects
  • NF-kappa B / biosynthesis
  • NF-kappa B / genetics
  • Oxalates / pharmacology
  • Piperazines / pharmacology
  • Protein Biosynthesis / drug effects
  • Protein Biosynthesis / genetics*
  • Rats
  • Signal Transduction / drug effects
  • Stress, Physiological / drug effects
  • Stress, Physiological / genetics*
  • Thapsigargin / pharmacology
  • eIF-2 Kinase / genetics*
  • eIF-2 Kinase / metabolism


  • NF-kappa B
  • Oxalates
  • Piperazines
  • Thapsigargin
  • eIF-2 Kinase