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bioRxiv · 10.1101/2021.04.06.438639

Maize RAMOSA3 accumulates in nuclear condensates enriched in RNA POLYMERASE II isoforms during the establishment of axillary meristem determinacy.

Demesa-Arevalo, E.·Abraham-Juarez, M. J.·Xu, X.·Bartlett, M.·Jackson, D.
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Abstract

Brief AbstractMaize meristem determinacy is regulated by Trehalose-6-Phosphate Phosphatase (TPP) metabolic enzymes RAMOSA3 and TPP4. However, this function is independent of their enzymatic activity, suggesting they have an unpredicted, or moonlighting function. Using whole-mount double immunolabeling and imaging processing, we investigated the co-localization of RA3 nuclear speckles with markers for transcription, chromatin state and splicing. We find evidence for RA3 co-localization with RNA POL II, a transcription marker, and not with markers for promoter chromatin remodeling or mRNA processing, suggesting a function of nuclear RA3 in mediating a transcriptional response during meristem determinacy.

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Demesa-Arevalo, E., Abraham-Juarez, M. J., Xu, X., Bartlett, M., Jackson, D.. 2021-04-06. Maize RAMOSA3 accumulates in nuclear condensates enriched in RNA POLYMERASE II isoforms during the establishment of axillary meristem determinacy.. https://doi.org/10.1101/2021.04.06.438639

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