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bioRxiv · 10.1101/2022.09.23.509183

The Transcriptome of Acute Dehydration in Myeloid Leukemia Cells

Welch, D. B. M.·Gould, T. J.·Olins, A. L.·Olins, D. E.
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Abstract

Live human myeloid leukemia (HL-60/S4) cells exposed to acute hyperosmotic stress with sucrose undergo dehydration and cell shrinkage. Interphase chromatin and mitotic chromosomes congeal, and exhibit altered phase separation (demixing) of chromatin-associated proteins. To investigate concurrent changes in the transcriptome, we exposed exponentially growing HL-60/S4 cells to acute hyperosmotic stress ([~]600 milliOsmolar) for 30 and 60 minutes by addition of sucrose to the culture medium. We employed RNA-Seq of polyA mRNA to identify genes with significantly increased or decreased transcript levels relative to untreated control cells (i.e., differential gene expression). These identified genes were examined for over-representation of Gene Ontology (GO) terms. In hyperosmotically-stressed cells, multiple GO terms associated with transcription, translation, mitochondrial function and proteosome activity, as well as the gene set "replication-dependent histones", were over-represented among genes with increased transcript levels; whereas, genes with decreased transcript levels were over-represented in various GO terms for transcription repressors. The overall transcriptome profiles of these stressed cells suggest a rapid acquisition of cellular rebuilding, a futile homeostatic response, as these cells are ultimately doomed to a dehydrated death. "Do not go gentle into that good night Rage, rage against the dying of the light" Dylan Thomas (1914-1953)

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Welch, D. B. M., Gould, T. J., Olins, A. L., Olins, D. E.. 2022-09-23. The Transcriptome of Acute Dehydration in Myeloid Leukemia Cells. https://doi.org/10.1101/2022.09.23.509183

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