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bioRxiv · 10.1101/656009

A Protein Kinase A-Regulated Network Encodes Short- and Long-Lived Cellular Memory

Jiang, Y.·AkhavanAghdam, Z.·Li, Y.·Zid, B. M.·Hao, N.
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Abstract

Cells can store memories of prior experiences to modulate their responses to subsequent stresses, as seen for the protein kinase A (PKA)-mediated general stress response in yeast, which is required for resistance against future stressful conditions. Using microfluidics and time-lapse microscopy, we quantitatively analyzed how cellular memory of stress adaptation is encoded in single yeast cells. We found that cellular memory is biphasic. Short-lived memory was mediated by trehalose synthase and trehalose metabolism. Long-lived memory was mediated by PKA-regulated stress-responsive transcription factors and cytoplasmic messenger ribonucleoprotein (mRNP) granules. Strikingly, short- and long-lived memory could be selectively induced by different priming input dynamics. Computational modeling revealed how the PKA-mediated regulatory network could encode previous stimuli into memories with distinct dynamics. This biphasic memory-encoding scheme, analogous to innate and adaptive immune responses in mammals, might represent a general strategy to prepare for future challenges in rapidly changing environments.

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Jiang, Y., AkhavanAghdam, Z., Li, Y., Zid, B. M., Hao, N.. 2019-05-31. A Protein Kinase A-Regulated Network Encodes Short- and Long-Lived Cellular Memory. https://doi.org/10.1101/656009

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