Genes are expressed through tightly controlled processes. The first step of gene expression is transcription, a cellular process by which a gene's DNA sequence is copied into RNA. Transcriptional bursting is a fundamental property of genes that allows large amounts of RNA to be produced in a short period of time. This process has been observed in diverse organisms, from bacteria to mammals. In this study, the researchers applied mathematical modeling to single-cell RNA sequencing data—information on the transcriptional activity of individual cells—to infer transcriptional bursting dynamics under multiple conditions. The researchers found that Mediator complex subunit 26 (MED26) had the most profound impact on the entire gene regulatory network, acting downstream of chromatin spatial architecture without affecting TATA box-binding protein recruitment, a key step that helps recruits transcription machinery to the gene. These findings suggest that later steps in the initiation of transcriptional bursts are primary nodes for integrating gene networks in single cells.