Identification of Arabidopsis genic and non-genic promoters

A promoter is a region that “determines the position, direction, frequency, and timing of transcription”.  A cell can decode the sequence of the promoter to ensure appropriate transcription, but we still can’t. Tokizawa et al. performed a large-scale survey of promoters by sequencing regions upstream of transcription start sites. They identified promoters corresponding to 80% of Arabidopsis protein-coding genes, as well as many non-coding RNA (miRNA and ncRNA) gene promoters, and intragenic, antisense, and orphan promoters. Onto each of these they mapped core elements (e.g., TATA box) and position-sensitive regulatory elements (REGs). In addition to providing a valuable resource, key findings include that genes average three promoters, and that genes encoding organelle-localized proteins often lack TATA boxes in spite of high expression levels. Plant J. 10.1111/tpj.13511