Auxin facilitates cell wall phosphorus reutilization in a nitric oxide-ethylene dependent manner in phosphorus deficient rice (Oryza sativa L.). (September 2022)

• Record Type: Journal Article
• Authors: Huang, Jing; Wu, Qi; Jing, Huai Kang; Shen, Ren Fang; Zhu, Xiao Fang
• Is Part Of: Plant science. Volume 322(2022)
• Publication Date: 2022-09
• Subjects: Auxin -- Cell wall -- NAA -- NO -- Phosphorus -- Reutilization; Botany -- Periodicals; Botanique -- Périodiques; 580
• DOI: 10.1016/j.plantsci.2022.111371
• Languages: English
• ISSNs: 0168-9452

Abstract

Abstract: Auxin is involved in stress responses of plants, such as phosphorus (P) deficiency in rice. Studies on whether auxin participates in cell-wall inorganic phosphorous (Pi) reutilization in Pi-starved rice are scarce. This study explored the mechanisms underlying auxin-facilitated cell-wall Pi-reutilization in rice roots. Pi deficiency rapidly induced auxin accumulation in roots; exogenous auxin [α-naphthaleneacetic acid (NAA), a permeable analog of auxin] elevated soluble Pi content in roots and shoots by increasing pectin content by enhancing activity of pectin methylesterase, and upregulating the transcript level of PHOSPHORUS-TRANSPORTER-2, such that more Pi was translocated to the shoot. Irrespective of the Pi status, exogenous auxin induced nitric oxide (NO) and ethylene production, while exogenous sodium nitroprusside (an NO donor) and 1-aminocyclopropane-1-carboxylic acid (a precursor of ethylene) had no effect on auxin content, suggesting that auxin may act upstream of NO and ethylene. The beneficial effect of NAA in increasing soluble Pi content in roots and shoots disappeared when 2-(4-carboxyphenyl)− 4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3-oxide (a scavenger of NO) or aminoethoxyvinylglycine (an inhibitor of ethylene) were applied, suggesting that auxin facilitates cell-wall Pi-reutilization in a NO-ethylene-dependent manner in Pi-deficient rice. Our study results suggest auxin application as an effective agronomic practice for improving plant Pi nutrition in P-deficient conditions. Graphical Abstract: ga1 Highlights: Auxin facilitates cell-wall inorganic P (Pi) reutilization in Pi-deficient rice. The Pi is reutilized in an NO-ethylene-dependent manner. Auxin accelerates translocation of Pi from root to shoot. Translocation of Pi is accelerated by elevating the transcript level of OsPT2.