Functional Characterization of a Putative RNA Demethylase ALKBH6 in <i>Arabidopsis</i> Growth and Abiotic Stress Responses
RNA methylation and demethylation, which is mediated by RNA methyltransferases (referred to as “writers”) and demethylases (referred to as “erasers”), respectively, are emerging as a key regulatory process in plant development and stress responses. Although several studies have shown that AlkB homol...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-09-01
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| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/21/18/6707 |
| Summary: | RNA methylation and demethylation, which is mediated by RNA methyltransferases (referred to as “writers”) and demethylases (referred to as “erasers”), respectively, are emerging as a key regulatory process in plant development and stress responses. Although several studies have shown that AlkB homolog (ALKBH) proteins are potential RNA demethylases, the function of most ALKBHs is yet to be determined. The <i>Arabidopsis thaliana</i> genome contains thirteen genes encoding ALKBH proteins, the functions of which are largely unknown. In this study, we characterized the function of a potential eraser protein, ALKBH6 (At4g20350), during seed germination and seedling growth in <i>Arabidopsis</i> under abiotic stresses. The seeds of T-DNA insertion <i>alkbh6</i> knockdown mutants germinated faster than the wild-type seeds under cold, salt, or abscisic acid (ABA) treatment conditions but not under dehydration stress conditions. Although no differences in seedling and root growth were observed between the <i>alkbh6</i> mutant and wild-type under normal conditions, the <i>alkbh6</i> mutant showed a much lower survival rate than the wild-type under salt, drought, or heat stress. Cotyledon greening of the <i>alkbh6</i> mutants was much higher than that of the wild-type upon ABA application. Moreover, the transcript levels of ABA signaling-related genes, including <i>ABI3</i> and <i>ABI4</i>, were down-regulated in the <i>alkbh6</i> mutant compared to wild-type plants. Importantly, the ALKBH6 protein had an ability to bind to both m<sup>6</sup>A-labeled and m<sup>5</sup>C-labeled RNAs. Collectively, these results indicate that the potential eraser ALKBH6 plays important roles in seed germination, seedling growth, and survival of <i>Arabidopsis</i> under abiotic stresses. |
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| ISSN: | 1661-6596 1422-0067 |