Kozak Sequence Acts as a Negative Regulator for De Novo Transcription Initiation of Newborn Coding Sequences in the Plant Genome

Abstract The manner in which newborn coding sequences and their transcriptional competency emerge during the process of gene evolution remains unclear. Here, we experimentally simulated eukaryotic origination processes by mimicking horizontal transfer events plant genome. We mapped precise position transcription start sites (TSSs) hundreds newly introduced promoterless firefly luciferase (LUC) genome Arabidopsis thaliana cultured cells. systematic characterization LUC-TSSs revealed that 80% them occurred under influence endogenous promoters, while remainder underwent de novo activation intergenic regions, starting from pyrimidine-purine dinucleotides. These TSSs obeyed unexpected rules; they predominantly ∼100 bp upstream LUC inserts did not overlap with Kozak-containing putative open reading frames (ORFs). features were output immediate responses to sequence insertions, rather than a bias screening function. Regarding wild-type genic TSSs, appeared have evolved lack any ORFs vicinities. Therefore, repulsion described above might be first selection gate for occurrence Based on these results, characterized type TSS identified discuss its significance evolution.