pHSE-Luc is designed to monitor the activation of heat shock factor (HSF) and heat shock-mediatedsignal transduction pathways. pHSE-Luc contains the firefly luciferase (luc) gene from Photinuspyralis (1). This vector also contains multiple copies of the HSE consensus sequence fused to aTATA-like promoter (PTAL) region from the Herpes simplex virus thymidine kinase (HSV-TK)promoter. After endogenous HSF binds the heat-shock element (HSE; 2), transcription is inducedand the reporter gene is activated.The luciferase coding sequence is followed by the SV40 late polyadenylation signal to ensureproper, efficient processing of the luc transcript in eukaryotic cells. Located upstream of HSE is asynthetic transcription blocker (TB), which is composed of adjacent polyadenylation and transcrip-tion pause sites for reducing background transcription (3). The vector backbone also contains an f1origin for single-stranded DNA production, a pUC origin of replication, and an ampicillin resistancegene for propagation and selection in E. coli.