Dose-dependent long-distance movement of microRNA399 duplex regulates phosphate homeostasis in Arabidopsis

© 2023 The Authors New Phytologist © 2023 New Phytologist Foundation.

Bibliographische Detailangaben
Veröffentlicht in:The New phytologist. - 1979. - 240(2023), 2 vom: 11. Okt., Seite 802-814
1. Verfasser: Chiang, Chih-Pin (VerfasserIn)
Weitere Verfasser: Li, Jia-Ling, Chiou, Tzyy-Jen
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2023
Zugriff auf das übergeordnete Werk:The New phytologist
Schlagworte:Journal Article Research Support, Non-U.S. Gov't PHO2 long-distance movement microRNA399 phosphate transport small RNA duplex Arabidopsis Proteins MicroRNAs Phosphates
Beschreibung
Zusammenfassung:© 2023 The Authors New Phytologist © 2023 New Phytologist Foundation.
MicroRNA399 (miR399), a phosphate (Pi) starvation-induced long-distance signal, is first produced in shoots and moves to roots to suppress PHO2 encoding a ubiquitin conjugase, leading to enhanced Pi uptake and root-to-shoot translocation. However, the molecular mechanism underlying miR399 long-distance movement remains elusive. Hypocotyl grafting with various Arabidopsis mutants or transgenic lines expressing artificial miR399f was employed. The movement of miR399 across graft junction and the rootstock PHO2 transcript and scion Pi levels were analyzed to elucidate the potential factors involved. Our results showed that miR399f precursors are cell-autonomous and mature miR399f movement is independent of its biogenesis, sequence context, and length (21 or 22 nucleotides). Expressing viral silencing suppressor P19 in the root stele or blocking unloading in the root phloem pore pericycle (PPP) antagonized its silencing effect, suggesting that the miR399f/miR399f* duplex is a mobile entity unloaded through PPP. Notably, the scion miR399f level positively correlates with its amount translocated to rootstocks, implying dose-dependent movement. This study uncovers the molecular basis underlying the miR399-mediated long-distance silencing in coordinating shoot Pi demand with Pi acquisition and translocation activities in the roots
Beschreibung:Date Completed 22.09.2023
Date Revised 24.09.2023
published: Print-Electronic
Citation Status MEDLINE
ISSN:1469-8137
DOI:10.1111/nph.19182