Epigenome regulators imbue a single eukaryotic promoter with diverse gene expression dynamics

Biological information can be encoded in signaling dynamics, which have been implicated in many physiological processes; yet the diversity of dynamic expression profiles driven by a single gene remains unclear. To explore this, we screen 80 chromatin-associated proteins (CAPs) for their potential to drive diverse dynamic gene expression profiles from the same genome-integrated reporter in yeast. Using locus-specific optogenetic recruitment and live-cell microscopy, we measure dynamic expression profiles within single cells. CAP recruitment elicits a range of responses varying in activation delay, strength, production rate, and noise. We find that promoter activity is characterized by graded, rather than switch-like, transitions. A kinetic model with three promoter states and a positive feedback loop successfully captures the key features of expression driven by each CAP. These results reveal the rich dynamic landscape possible from a single gene, offering insights into native cellular processes and enhancing gene expression control in synthetic biology.

bioinformatics; biological sciences; evolutionary biology; natural sciences; synthetic biology.