Effects of the Rewiring of Promoter Activity States on Gene Expression

摘要

Gene transcription takes place often in a bursty manner. The gene promoters contain multiple activity states which compose complex patterns via chromatin remodeling. An entirely unexplored question is how the rewiring of promoter activity states affects gene expression. Here, we systematically analyze and compare two representative models of stochastic transcription: the one is that promoter activity states form a chain-type structure and the other is that they form a star-type structure. After the theoretical analysis and the numerical simulation, some interesting phenomena have been found. Specifically, both the increase in the mean level of mRNA and the decrease in the expression noise are quicker in the chain -type structure than in the star-type structure with the enhanced recruitment mechanism. The recruitment mechanism strength has unchanged the change rate of mean burst frequency in the chain-type structure but reduced it in the star-type structure. The star-type structure has shorter first passage time but more fluctuations than the chain-type structure. These results indicate that the transcription outcome is of promoter architecture-specific.