Coronatine inhibits mesocotyl elongation by promoting ethylene production in etiolated maize seedlings
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Maize (Zea mays L.) is one of the most important cereal crops in the world. In order to survive, plants must regulate their growth in response to multiple developmental and environmental cues, including modulating lodging stress. Coronatine is a chlorosis-inducing non-host-specific phytotoxin produced by several members of the Pseudomonas syringe group of pathovars, which can lead to leaf chlorosis, anthocyanin production, and growth inhibition. In this study, we investigated the physiological mechanism for coronatine during maize mesocotyl growth and development. Using ethephon as a positive control, we found that coronatine inhibited the elongation of mesocotyls in maize B73 etiolated seedlings which was related to ethylene production. Both coronatine and ethephon increased mesocotyls coarsening by increasing the cell diameter and shortened it by inhibiting cell elongation. Coronatine also thickened cell walls in longitudinal and transverse sections by increasing the expression of the cellulose lignin synthesis gene ZmEXT. To further verify the correlation between coronatine and ethephon during mesocotyl growth, we detected the release of endogenous ethylene and the expression of ZmACOs and ZmACSs. We found that coronatine increased the ethylene production while inhibiting auxin synthesis, thereby inhibiting mesocotyl growth.
KeywordsMaize seedling Coronatine Ethephon Parenchyma cell Elongation Mesocotyl
This study was funded by Grants from The National Science Fund for Distinguished Young Scholars (Grant No. 31425017) & The National Key Research and Development Program of China (Grant No. 2017YFD0300405-2.
LD, YZ, YL designed the research; YL performed the experiments with the assistance of YZ, GH and NZ; YL analyzed the data; ZL and MZ gave some important suggestion; YL wrote the paper. All authors reviewed the manuscript.
- Ishimaru Y, Hayashi K, Suzuki T, Fukaki H, Prusinska J, Meester C, Quareshy M, Egoshi S, Matsuura H, Takahashi K, Kato N, Kombrink E, Napier RM, Hayashi K, Ueda M (2018) Jasmonic acid inhibits auxin-induced lateral rooting independently of the CORONATINE INSENSITIVE1 Receptor. Plant Physiol 177:1704–1716PubMedPubMedCentralCrossRefGoogle Scholar
- Park JH, Halitschke R, Kim HB, Baldwin IT, Feldmann KA, Feyereisen R (2002) A knock-out mutation in allene oxide synthase results in male sterility and defective wound signal transduction in Arabidopsis due to a block in jasmonic acid biosynthesis. Plant J 31:1–12PubMedCrossRefPubMedCentralGoogle Scholar
- Pauwels L, Morreel K, Witte ED, Lammertyn F, Montagu MV, Boerjan W, Lnze D, Goossens A (2008) Mapping methyl jasmonate-mediated transcriptional reprogramming of metabolism and cell cycle progression in cultured Arabidopsis cells. Proc Natl Acad Sci USA 105:1380–1385PubMedCrossRefPubMedCentralGoogle Scholar
- Uppalapati SR, Yasuhiro I, Tamding W, Ewa UW, Takako I, Kirankumar SM, Bender CL (2008) Pathogenicity of Pseudomonas syringae pv. tomato on tomato seedlings: phenotypic and gene expression analyses of the virulence function of coronatine. Mol Plant Microbe Interact 21:383–395PubMedCrossRefPubMedCentralGoogle Scholar
- Yang SW, Jang IC, Henriques R, Chua NH (2009) FAR-RED ELONGATED HYPOCOTYL1 and FHY1-LIKE associate with the Arabidopsis transcription factors LAF1 and HFR1 to transmit phytochrome A signals for inhibition of hypocotyl elongation. Plant Cell 211:341–1359Google Scholar
- Zhu ZQ, An FY, Feng Y, Li PP, Xue L, Mu A, Jiang ZQ, Kim JM, To TK, Li W, Zhang XY, Yu Q, Dong Z, Chen WQ, Seki M, Zhou JM, Guo HW (2011) Derepression of ethylene-stabilized transcription factors (EIN3/EIL1) mediates jasmonate and ethylene signaling synergy in Arabidopsis. Proc Natl Acad Sci USA 108:12539–12544PubMedCrossRefGoogle Scholar