A novel HAC1-based dual-luciferase reporter vector for detecting endoplasmic reticulum stress and unfolded protein response in yeast Saccharomyces cerevisiae

• We developed a dual-luciferase UPR reporter system.
• The system can be used to monitor UPR activation in live cells of the yeast Saccharomyces cerevisiae.
• The vector takes advantage of the HAC1 intron and its unconventional splicing-regulation mechanism.
• This HAC1-based dual-luciferase reporter vector can be used to monitor UPR in live cells with high sensitivity.

Unfolded protein response (UPR) is an important cellular phenomenon induced by over-accumulation of unfolded proteins in the endoplasmic reticulum (ER) lumen. ER stress and UPR are implicated in human diseases such as diabetes, atherosclerosis and neurodegenerative diseases. Current methods for measuring ER stress levels and UPR activation usually include cells lysis and other complicated procedures such as reverse transcription-PCR (RT-PCR). These methods typically have low sensitivity and are not suitable for live detection. In this study, we developed a dual-luciferase gene reporter system to monitor UPR activation in live cells of the yeast Saccharomyces cerevisiae by taking advantage of the HAC1 intron and its unconventional splicing-regulation mechanism. We showed that this reporter can be used to monitor UPR in live cells with high sensitivity.