Curated Optogenetic Publication Database

Abstract: Transcription factor nucleocytoplasmic dynamics play a key role in developmental gene regulation. In Dictyostelium , the transcription factor GtaC exhibits nucleocytoplasmic shuttling, but its shuttling trajectory across multicellular aggregation has not been systematically quantified. Using a knock-in strain, we tracked GtaC dynamics from starvation through aggregation and quantified developmental changes in shuttling period, amplitude, and synchrony. Notably, brief-pulse optogenetic activation of cAMP at higher input frequencies reproduced the reported attenuation of GtaC shuttling amplitude with high temporal precision and minimal phototoxicity. Together, long-term quantification and brief-pulse optogenetic cAMP perturbation show that GtaC nucleocytoplasmic shuttling is developmentally tuned in a frequency-dependent manner.

Abstract: Oscillatory dynamics and their modulation are crucial for cellular decision-making; however, analysing these dynamics remains challenging. Here, we present a tool that combines the light-activated adenylate cyclase mPAC with the cAMP biosensor Pink Flamindo, enabling precise manipulation and real-time monitoring of cAMP oscillation frequencies in Dictyostelium. High-frequency modulation of cAMP oscillations induced cell aggregation and multicellular formation, even at low cell densities, such as a few dozen cells. At the population level, chemotactic aggregation is driven by modulated frequency signals. Additionally, modulation of cAMP frequency significantly reduced the amplitude of the shuttling behaviour of the transcription factor GtaC, demonstrating low-pass filter characteristics capable of converting subtle oscillation changes, such as from 6 min to 4 min, into gene expression. These findings enhance our understanding of frequency-selective cellular decoding and its role in cellular signalling and development.