Signaling Mechanism of Transcriptional Bursting: A Technical Resolution-Independent Study

• Main Authors: Yaolai Wang, Jiaming Qi, Jie Shao, Xu-Qing Tang
• Format: Article
• Language: English
• Published: MDPI AG 2020-10-01
• Series: Biology
• Subjects: transcriptional bursts; transcription regulation; cell signaling; stochasticity of gene expression; noise; burst cluster
• Online Access: https://www.mdpi.com/2079-7737/9/10/339

Gene transcription has been uncovered to occur in sporadic bursts. However, due to technical difficulties in differentiating individual transcription initiation events, it remains debated as to whether the burst size, frequency, or both are subject to modulation by transcriptional activators. Here, to bypass technical constraints, we addressed this issue by introducing two independent theoretical methods including analytical research based on the classic two-model and information entropy research based on the architecture of transcription apparatus. Both methods connect the signaling mechanism of transcriptional bursting to the characteristics of transcriptional uncertainty (i.e., the differences in transcriptional levels of the same genes that are equally activated). By comparing the theoretical predictions with abundant experimental data collected from published papers, the results exclusively support frequency modulation. To further validate this conclusion, we showed that the data that appeared to support size modulation essentially supported frequency modulation taking into account the existence of burst clusters. This work provides a unified scheme that reconciles the debate on burst signaling.