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bioRxiv · 10.1101/2021.09.09.459632

Transcriptional networks underpinning ploidy related increased leaf potassium in neo-tetraploids

Fischer, S.·Flis, P.·Zhao, F.-J.·Salt, D. E.
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Abstract

Neo-tetraploid Arabidopsis thaliana have elevated leaf potassium (K) driven by processes within the root. The root transcriptome of neo-tetraploids is distinct from diploids, with evidence of altered K homeostasis. Mutational analysis revealed that the canonical K-uptake transporters AKT1 and HAK5 are not required for this elevated leaf K in neo-tetraploids, while the endodermis, root hairs, and SOS signaling are. Contrasting the root transcriptomes of neo-tetraploids and diploids of mutants that block the neo-tetraploid K phenotype, allowed us to identify 91 differentially expressed genes associated with elevated leaf K in neo-tetraploids. This set of genes connects WGD to elevated leaf K, and is enriched in functions such as cell wall and Casparian strip development, and ion-transport, in the endodermis, root hairs, and procambium. This gene set provides tools to test the intriguing idea of recreating the physiological effects of WGD within a diploid genome.

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Fischer, S., Flis, P., Zhao, F.-J., Salt, D. E.. 2021-09-11. Transcriptional networks underpinning ploidy related increased leaf potassium in neo-tetraploids. https://doi.org/10.1101/2021.09.09.459632

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