A New Role For Green Leaf Volatile Esters in Tomato Stomatal Defense Against Pseudomonas syringe pv. tomato.
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ABSTRACT:
SUBMITTER: Lopez-Gresa MP
PROVIDER: S-EPMC6305539 | biostudies-literature | 2018
REPOSITORIES: biostudies-literature
Publications
A New Role For Green Leaf Volatile Esters in Tomato Stomatal Defense Against <i>Pseudomonas syringe</i> pv. <i>tomato</i>.
López-Gresa María Pilar MP Payá Celia C Ozáez Miguel M Rodrigo Ismael I Conejero Vicente V Klee Harry H Bellés José María JM Lisón Purificación P
Frontiers in plant science 20181218
The volatile esters of (Z)-3-hexenol with acetic, propionic, isobutyric, or butyric acids are synthesized by alcohol acyltransferases (AAT) in plants. These compounds are differentially emitted when tomato plants are efficiently resisting an infection with <i>Pseudomonas syringae</i> pv. <i>tomato</i>. We have studied the defensive role of these green leaf volatile (GLV) esters in the tomato response to bacterial infection, by analyzing the induction of resistance mediated by these GLVs and the ...[more]
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Each photograph also contained a standard of known area, from which leaf area and % damage calculations were determined (Sigma Scan 500, Systat Software Inc.). Larvae consumed similar amounts on the treatment and control leaves (24 hours: z3HAC-treated leaves: 4.7 ± 1.8 cm2; controls: 4.3 ± 1.7 cm2). The snap-frozen leaves were stored at -80oC until grinding. Each leaf was ground in an individual mortar and pestle under liquid N2. Ground tissue was weighed into vials for RNA extraction and JA analysis (see below). Care was taken to not allow the ground tissue to thaw at any point prior to extraction. This method therefore allowed us to measure gene expression and JA from the same tissue. Microarray Analysis To explore a transcriptome-level response of poplar leaves to z3HAC and herbivory, we conducted microarray analysis of the samples collected after 24 hours of herbivore damage. This allowed a comparison of transcriptome-level responses to herbivory in z3HAC-treated versus untreated leaves (i.e., the set of genes that were primed by z3HAC exposure). Total RNA was labeled using Ambion's Amino Allyl Message Amp II aRNA Amplification Kit (#AM1753) according to the manufacturer's instructions. Briefly, 1 ug of each sample was reversed transcribed using T7-oligo(dT) priming and subsequently second strand cDNA synthesis was performed. The resulting double stranded cDNA was purified and then used as a template for in vitro transcription during which amino allyl-modified UTP was incorporated. The resulting amino allyl-modified cRNA was purified and coupled with Cy3 or Cy5 (GE Amersham, #RPN5661) as appropriate. We used dye swapping to account for potential dye effects. Dye coupled cRNA was purified and 4 ug was fragmented and subsequently dissolved in 60ul of hybridization solution. We used an aspen 7K EST array containing replicate subarrays of 6,705 elements in a 4Ã4 grid with a spot diameter of ~150 µm and a spacing of 200 µm (Ranjan et al., 2004). The elements represented ~5,400 unique JGI Populus gene models, and included positive and negative controls (Lucidea Universal ScoreCard, Amersham) to monitor target labeling and hybridization efficiency, as well as many genes of known function. Clone information can be downloaded from the aspenDB website (www.aspenDB.mtu.edu). Arrays were hybridized following previously published methods (Xiang et al., 2002; Hughes et al., 2001). Chang S, Puryear J, Cairney J. 1993. A simple and efficient method for isolating RNA from pine trees. Plant Molecular Biology Reporter 11: 113-116. Davis JM, Gordon MP, Smit BA. 1991. Assimilate movement dictates remote sites of wound-induced gene expression in poplar leaves. Proceedings of the National Academy of Sciences (USA) 88: 2393-2396. Frost CJ, Appel HM, Carlson JE, De Moraes CM, Mescher MC, Schultz JC. 2007. Within-plant signalling via volatiles overcomes vascular constraints on systemic signalling and primes responses against herbivores. Ecology Letters 10: 490-498. Hughes TR, Mao M, Jones AR, Burchard J, Marton MJ, Shannon KW, Lefkowitz SM, Ziman M, Schelter JM, Meyer MR, Kobayashi S, Davis C, Dai HY, He YDD, Stephaniants SB, Cavet G, Walker WL, West A, Coffey E, Shoemaker DD, Stoughton R, Blanchard AP, Friend SH, Linsley PS. 2001. Expression profiling using microarrays fabricated by an ink-jet oligonucleotide synthesizer. Nature Biotechnology 19: 342-347. Xiang CC, Kozhich OA, Chen M, Inman JM, Phan QN, Chen YD, Brownstein MJ. 2002. Amine-modified random primers to label probes for DNA microarrays. Nature Biotechnology 20: 738-742.
2010-05-25 | E-GEOD-11955 | biostudies-arrayexpress
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