Detect chemical or genetic stress, and identify compounds that reverse the stress response with this live cell fluorescent assay. Measure ER stress responses via the XBP1/IRE1 arm of the UPR. Add the cell stress sensor to your cells and measure robust signals the next day on a fluorescence imaging system or automated plate reader. Increasing green fluorescence indicates ER Stress or UPR activation. Constitutively expressed red fluorescent protein can be used to identify transduced cells. This assay is genetically encoded and packaged in BacMam for efficient transduction in most cell types - including uniform and near 100% efficiency in HEK293 cells as well as expression in many primary or iPSC-derived cells. The kit includes the ER stress sensor BacMam, 500mM sodium butyrate in H2O, and a positive control agonist (1mM thapsigargin in DMSO). 10mL and 30mL sizes are available as well. Other Montana Molecular tools including BacMam-packaged proteins associated with neurodegeneration like Rhodopsin, TDP-43, and SOD1 can easily be co-expressed with this assay. Assays such as the cADDis cAMP assay can be used to investigate changes in signaling in stressed cells.