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, high-density TSS analysis of Arabidopsis revealed that many protein-coding genes have neither TATA-box nor Inr, but 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 these genes. In this study, we examined how protein-coding genes recruit TSS close to their 5' termini, with the aid of transgenic plants carrying various chimeric constructs and of chromatin immunoprecipitation analysis with antibodies against the components of PIC (transcriptional preinitiation complex) and nucleosomes. The obtained results indicate that the insertion of the protein-coding region in the plant genome could cause the chromatin remodeling around their 5' termini, recruiting the PIC and causes TSS. Analysis of the underlying mechanism is in progress.
