In Chemistry and Biology the term “Promoter” has got two meanings, first: 1. (Chemistry) a substance added in small amounts to a catalyst to increase its activity 2. (Genetics) a sequence of nucleotides, associated with a structural gene, that must bind with messenger RNA polymerase before transcription can proceed In this paper Glial Cells and Their Function in the Adult Brain: A Journey through the History of Their Ablation https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5303749/ the term “Promoter” is used several times, for example: “Nowadays, most ablation approaches make use of a cell type or a region-specific promoter that is coupled with a “suicide” gene, resulting in depletion of distinct cell types.” “Unlike in the healthy CNS where microglia-targeting was achieved with the CX3CR1-promoter (see section Microglia Ablation under Healthy Conditions), all studies investigating the role of microglia in disease models use the CD11b-promoter that is also expressed in cells of myeloid origin, including both microglia and macrophages.” “Suicide gene expression exploited for this cell population has mainly made use of the intermediate filament glial fibrillary acidic protein (GFAP) promoter that is only expressed by a subset of astrocytes in specific regions of the healthy brain (Takamiya et al., 1988; Cahoy et al., 2008).” and so on. I am bit confused. Which promoter is meant here? Definitely not the biological one, that is the part of DNA strand, right? Because in the first citation it is written that “region-specific promoter that is coupled with a “suicide” gene”, but both (structural) gene and promotor are part of DNA molecules/strands, how they can be coupled? But if the “chemical” promoter is used then the situation is a bit obscure. As far as I remember for transcription not the promoter is needed but the transcription factors, right? So, what can you tell me?