Transcriptomic basis for reinforcement of elm antiherbivore defence mediated by insect egg deposition

Abstract

Plant responses to insect egg depositions are known to shape subsequent defensive responses to larvae hatching from the eggs. Elm (Ulmus minor) leaves, on which elm leaf beetles laid their eggs, mount a more efficient defence against larvae hatching from the eggs. However, the molecular mechanisms of this egg‐mediated, improved defence are insufficiently understood and have so far only been studied in annual plants. We analysed the dynamics of transcriptomic changes in larval feeding‐damaged elm leaves with and without prior egg deposition using de novo assembled RNA‐seq data. Compared to egg‐free leaves, egg deposition‐treated leaves showed earlier and/or faster transcriptional regulations, as well as slightly enhanced differential transcriptional regulation after the onset of larval feeding. These early responding transcripts were overrepresented in gene ontology terms associated with post‐translational protein modification, signalling and stress (defence) responses. We found evidence of transcriptional memory in initially egg deposition‐induced transcripts whose differential expression was reset prior to larval hatching, but was more rapidly induced again by subsequent larval feeding. This potential memory effect of prior egg deposition, as well as the earlier/faster and enhanced feeding‐induced differential regulation of transcripts in egg deposition‐treated leaves, may contribute to the egg‐mediated reinforcing effect on the elm's defence against larvae. Hence, our study shows that a plant's experience of a stress‐indicating environmental cue (here: insect eggs) can push the dynamics of the plant's transcriptomic response to subsequent stress (here: larval feeding). Such experience‐mediated acceleration of a stress‐induced plant response may result in improved stress resistance.

Arabidopsis, tobacco, nightshade and elm take insect eggs as herbivore alarm and show similar transcriptomic alarm responses

“…Our analysis, and the earlier original publications 12 , 17 , 21 , 22 , 24 to which our analysis refers, found prominent regulation of GS related to phytohormone signalling. Therefore, we compared the enrichment of all GS associated with phytohormone signalling and metabolism that were up- or down-regulated in at least one of the species combinations (Fig.…”

“…The experimental data were mostly one-colour microarray data 12 , 17 , 21 , 22 , with the exception of the U. minor datasets 24 , which originated from an RNA-seq experiment (Fig. 1 a).…”

“…Elevated transcription of SA-related GS in response to insect eggs has frequently been described but the conserved induction of JA-, ET-, and ABA-related GS is surprising. Enhanced activation of JA signalling is plausible for U. minor because the leaves in this dataset were mechanically wounded to mimic the leaf damage inflicted by the beetles during egg deposition 24 . The wound stimulus alone might have elicited the induction of JA-mediated pathways in the egg treatment 45,46 .…”

“…1 a). For the analysis we used transcriptomic data from published experiments with A. thaliana infested by P. brassicae 17 , N. attenuata infested by M. sexta or by S. exigua 21 , S. dulcamara infested by S. exigua 12 , 22 and U. minor infested by the leaf beetle Xanthogaleruca luteola 24 . Thus, our analysis is based on transcriptomic data obtained by studies of different plant–insect combinations, including plant species with very different life strategies, as well as lepidopteran and coleopteran insect species.…”

Boric Acid (H3(BO3): Recognize The Molecular Interactions in Solutions

“…Kelarutan dalam pelarut lain (19) Warna (8) Wujud (12) Bentuk Molekul (18) Asam metaborat akan mencair jika diberikan pemanasan sekitar 236 °C, dan ketika dipanaskan pada suhu (101) di atas 300 °C dia akan kehilangan air (102) (103) larutan (solutions) (104) asam borat cair. Spektroskopi Ramandi pada larutan (201)(202)(203)(204)(205) basa kuat menerangkan bahwa terdapat ion B(OH) −4 , sehingga berdasarkan beberapa penelitian disimpulkan bahwa keasaman secara khusus terjadi karena abstraksi OHdari H 2 O (39) : B(OH) 3 + H 2 O B(OH) −4 + H + (K = 7.3x10 −10 ; pK = 9.14) atau lebih jelasnya dinyatakan dalam larutan:…”