Arabidopsis DXO1 links RNA turnover and chloroplast function independently of its enzymatic activity.
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ABSTRACT:
SUBMITTER: Kwasnik A
PROVIDER: S-EPMC6511867 | biostudies-literature | 2019 May
REPOSITORIES: biostudies-literature
Publications
Arabidopsis DXO1 links RNA turnover and chloroplast function independently of its enzymatic activity.
Kwasnik Aleksandra A Wang Vivien Ya-Fan VY Krzyszton Michal M Gozdek Agnieszka A Zakrzewska-Placzek Monika M Stepniak Karolina K Poznanski Jaroslaw J Tong Liang L Kufel Joanna J
Nucleic acids research 20190501 9
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Project description:The DXO family of proteins participates in eukaryotic mRNA 5'-end quality control, removal of non-canonical NAD+ cap and maturation of fungal rRNA precursors. In this work, we characterize DXO1, the Arabidopsis thaliana DXO homolog. We demonstrate that the plant-specific modification within the active site negatively affects 5'-end capping surveillance properties of DXO1, but has only a minor impact on its strong deNADding activity. Unexpectedly, catalytic activity does not contribute to striking morphological and molecular aberrations observed upon DXO1 knockout in plants, which include growth and pigmentation deficiency, global transcriptomic changes and accumulation of RNA quality control siRNAs. Conversely, these phenotypes depend on the plant-specific N-terminal extension of DXO1. Pale-green coloration of DXO1-deficient plants and our RNA-seq data reveal that DXO1 affects chloroplast-localized processes. We propose that DXO1 mediates the connection between RNA turnover and retrograde chloroplast-to-nucleus signaling independently of its deNADding properties. Founded by National Science Centre Grant, Poland (UMO-2013/08/M/NZ1/00931, UMO-2018/29/B/NZ3/01980, UMO‐2021/40/Q/NZ1/00014, UMO‐2014/13/B/NZ3/00405, MINIATURA 2017/01/X/NZ1/00332, UMO‐2021/41/B/NZ3/02605).
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