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bioRxiv · 10.1101/2021.12.09.471914

Kinetic characteristics of transcriptional bursting in a complex gene model with cyclic promoter structure

Yang, X.·Wang, Z.·Wu, Y.·Zhou, T.·Zhang, J.
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Abstract

While transcription occurs often in a bursty manner, various possible regulations can lead to complex promoter patterns such as promoter cycles, giving rise to an important issue: How do promoter kinetics shape transcriptional bursting kinetics? Here we introduce and analyze a general model of the promoter cycle consisting of multi-OFF states and multi-ON states, focusing on the effects of multi-ON mechanisms on transcriptional bursting kinetics. The derived analytical results indicate that bust size follows a mixed geometric distribution rather than a single geometric distribution assumed in previous studies, and ON and OFF times obey their own mixed exponential distributions. In addition, we find that the multi-ON mechanism can lead to bimodal burst-size distribution, antagonistic timing of ON and OFF, and diverse burst frequencies, each further contributing to cell-to-cell variability in the mRNA expression level. These results not only reveal essential features of transcriptional bursting kinetics patterns shaped by multi-state mechanisms but also can be used to the inferences of transcriptional bursting kinetics and promoter structure based on experimental data.

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Yang, X., Wang, Z., Wu, Y., Zhou, T., Zhang, J.. 2021-12-09. Kinetic characteristics of transcriptional bursting in a complex gene model with cyclic promoter structure. https://doi.org/10.1101/2021.12.09.471914

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