pAP1(PMA)-TA-Luc is a member of the signal transduction reporter vectors. It is designed formonitoring the induction of the protein kinase C (PKC) signal transduction pathway, as well as relatedpathways such as the MAPK pathway. pAP1(PMA)-TA-Luc contains the firefly luciferase gene (luc)as the reporter. The vector contains multiple copies of the activator protein 1 (AP1) enhancer, locatedupstream of luc, that responds specifically to phorbol ester treatment (1). AP1(PMA) is fused to aminimal TA promoter, the TATA box from the Herpes simplex virus thymidine kinase (HSV-TK) promoter.The luciferase coding sequence is followed by the SV40 late polyadenylation signal to ensure proper,efficient processing of the luciferase transcript in eukaryotic cells. A synthetic transcription blocker (TB)is located upstream of AP1(PMA), which is composed of adjacent polyadenylation and transcriptionpause sites for blocking nonspecific transcription (2). The vector backbone also contains an f1 originfor single-stranded DNA production, a pUC origin of replication, and an ampicillin resistance genefor propagation and selection in E. coli.