Ratiometric Fluorescent Detection of
Cellular Stress & Toxicity

The cell stress sensor is a genetically-encoded fluorescent biosensor that produces very bright fluorescence when the cell endures endoplasmic reticulum (ER) stress or undergoes the unfolded protein response (UPR). The biosensor is a two-color biosensor, allowing ratiometric detection of cellular stress and toxicity. The fluorescent ratio between the constitutively expressed, nuclear localized, red fluorescent protein and the stress induced, nuclear localized, green fluorescent protein is calculated to determine the level of cellular stress. A broad host of both chemical compounds and genetic mutations can induce ER stress. The UPR is one of the major stress pathways within the cell, which allows the stress sensor to detect a wide range of stress inducing stimuli, some whose primary target is not the ER.

Make Discoveries

Cell Stress BacMam Kits

US & Canada Prices:
10 mL … $595
30 mL … $1195
60 mL … $1795

Outside the US & Canada? Please check with regional distributors for local pricing.

Plate Reader or Microscope Compatible

Bright Green Fluorescence Response

Detect a wide range of cell stress

including ER and UPR

Molecular Mechanism

This sensor is based on the XBP1 mRNA which is spliced by the IRE1 protein during ER stress. Briefly, the model for this response involves ER stress activating the RNase activity of the IRE1 protein, which in turn splices the immature, cytosolic mRNA for XBP1, generating an active transcription factor that alters gene expression. This unique cytosolic splicing of XBP1 has been used to generate reporter systems in the past [Iwawaki et al. 2003], many of which were PCR-based splicing assays or reporters of XBP1 transcriptional activity [Rong et al. 2015]. The cell stress sensor is unique in that the assay does not rely on changes in gene expression or transcription activation. Rather, the splicing of the XBP1 intron results in translation of the bright fluorescent protein, mNeon Green. Increased translation of mNeon Green results in increased fluorescence output, indicating theoccurrence of cellular stress.

More Information

Protocols can be found in our main menu across the top of the page or by clicking the link below:

•  Cell Stress Sensor Protocol

Read about BacMam expression in different cell types



• K. Harlen, J. Quinn, T. Hughes, A.M. Quinn. New Fluorescent Tools to Monitor Cell Stress and Toxicity. SLAS 2018 Poster

• Yoshida, H., Matsui, T., Yamamoto, A., Okada, T. & Mori, K. XBP1 mRNA is induced by ATF6 and spliced by IRE1 in response to ER stress to produce a highly active transcription factor. Cell 107, 881–891 (2001).

coming soon

In your Cell Stress Sensor Kit:

  • 10, 30, or 60 mL of Sensor
  • HDAC Inhibitor (Sodium Butyrate)
  • Thapsigargin (positive control)

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