Nup98-dependent transcriptional memory is established independently of transcription [article]

Maya Capelson, Pau Pascual-Garcia, Shawn Little
2020 bioRxiv   pre-print
Cellular ability to mount an enhanced transcriptional response upon repeated exposure to external cues is termed transcriptional memory. This phenomenon can be maintained epigenetically through cell divisions and has been found to depend on a nuclear pore component Nup98. To gain a population dynamics perspective on the mechanism of transcriptional memory, we combined single-molecule RNA FISH with mathematical modeling to examine transcriptional behavior of individual Drosophila cells upon
more » ... ila cells upon initial and subsequent exposures to steroid hormone ecdysone. We found that upon hormone exposure, cells rapidly activate a low-level transcriptional response, but simultaneously, begin slow transitioning into a Nup98-dependent memory state, characterized by high expression. Strikingly, our modeling predicted that this transition into the memory state is independent of transcription during initial induction, and we were able to confirm this prediction experimentally. Together, our findings reveal that induced genes engage in two separate behaviors – transcription and establishment of epigenetic transcriptional memory.
doi:10.1101/2020.10.12.336073 fatcat:6xnx4styyreabn3rhzwevrvcui