Determination Mechanism of Transcription Start Sites in Photosynthetic TATA-less Promoters

Abstract

In the protein-coding genes of plants, core promoter elements such as TATA-box and initiator (Inr) are thought to be the cis-determinants of transcription start sites (TSS). However, many of the nuclear-encoded PSI genes have neither TATA-box nor Inr. Furthermore, these genes have multiple TSS distributed over tens of nucleotides. Therefore it is likely that some alternative to the classical core promoter elements should determine the TSS of PSI genes. In order to reveal the possible cis-elements that deterimine the TSS of PSI genes, we made a series of chimeric promoter constructs and introduced them into Arabidopsis. The analysis of the transgenic plants suggests that a novel cis-determinant for TSS should be located downstream of TSS. We would like to show further characterization of this novel element in this talk.