Miniature inverted repeat transposable elements cis-regulate circular RNA expression and promote ethylene biosynthesis, reducing heat tolerance in Populus tomentosa
© The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissionsoup.com.
Veröffentlicht in: | Journal of experimental botany. - 1985. - 72(2021), 5 vom: 27. Feb., Seite 1978-1994 |
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1. Verfasser: | |
Weitere Verfasser: | , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2021
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Zugriff auf das übergeordnete Werk: | Journal of experimental botany |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Populus cis-regulatory mechanism CircRNA MITEs exon circularization heat tolerance DNA Transposable Elements Ethylenes |
Zusammenfassung: | © The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissionsoup.com. Transposable elements (TEs) and their reverse complementary sequence pairs (RCPs) are enriched around loci that produce circular RNAs (circRNAs) in plants. However, the function of these TE-RCP pairs in modulating circRNA expression remains elusive. Here, we identified 4609 circRNAs in poplar (Populus tomentosa) and showed that miniature inverted repeat transposable elements (MITEs)-RCPs were enriched in circRNA flanking regions. Moreover, we used expression quantitative trait nucleotide (eQTN) mapping to decipher the cis-regulatory role of MITEs. eQTN results showed that 14 single-nucleotide polymorphisms (SNPs) were significantly associated with Circ_0000408 and Circ_0003418 levels and the lead associated SNPs were located in MITE-RCP regions, indicating that MITE-RCP sequence variations affect exon circularization. Overexpression and knockdown analysis showed that Circ_0003418 positively modulated its parental gene, which encodes the RING-type E3 ligase XBAT32, and specifically increased the expression of the PtoXBAT32.5 transcript variant, which lacks the E3 ubiquitin ligase domain. Under heat stress, PtoXBAT32.5 expression was induced with up-regulation of Circ_0003418, resulting in increased production of ethylene and peroxidation of membrane lipids. Our findings thus reveal the cis-regulatory mechanism by which a MITE-RCP pair affects circRNA abundance in poplar and indicate that Circ_0003418 is a negative regulator of poplar heat tolerance via the ubiquitin-mediated protein modification pathway |
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Beschreibung: | Date Completed 20.05.2021 Date Revised 20.05.2021 published: Print Citation Status MEDLINE |
ISSN: | 1460-2431 |
DOI: | 10.1093/jxb/eraa570 |