Transcriptomic and Metabolomic Responses of Rice Plants to Cnaphalocrocis medinalis Caterpillar Infestation

Abstract

Interactions between plants and insect herbivores are important determinants of plant productivity in cultivated and natural agricultural fields. The rice leaf folder (Cnaphalocrocis medinalis) causes tremendous damage to rice production in Asian countries. However, little information is available about how rice plants defend themselves against this destructive pest at molecular and biochemical levels. Here, we observed the transcriptomic and metabolomic differences in rice leaves after 0, 1, 6, 12, and 24 h of being fed by C. medinalis using RNA sequencing and metabolome profiling. Transcriptional analyses showed that gene expression responds rapidly to leaf folder infestation, with the most significant transcriptional changes occurring within 6 h after the initiation of feeding. Metabolite abundance changed more slowly than gene expression. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated that the rice transcriptional response to infestation involved genes encoding protein kinases, transcription factors, biosynthesis of secondary metabolites, photosynthesis, and phytohormone signaling. Moreover, the jasmonic acid-dependent signaling pathway triggered by leaf folder herbivory played a vital role in rice defense against this pest. Taken together, our results provide comprehensive insights into the defense system of rice to this species and may inform the development of insect-resistant rice varieties.

Proteomics and Metabolomics Studies on the Biotic Stress Responses of Rice: an Update

“…Phytohormones are also a key response exploited by rice and pathogens. In order to induce a defense response, rice plants upregulate SA signaling when exposed to M. oryzae (Meng et al 2019;Azizi et al 2019), JA when exposed to insects (Zhang et al 2019;Wang et al 2020), and both SA and JA when exposed to R. solani (Ma et al 2020a). PGPR also support rice defense via the induction of SA, as reported for Pseudomonas (Kandaswamy et al 2019), or the induction of ABA signaling and suppression of SA signaling via the bioactive SM cytosinpeptidemycin in response to Streptomyces (Yu et al 2018).…”

“…These studies confirmed a potential metabolic target but emphasized the limitations associated with studying and utilizing metabolites, especially phytohormones, whose balance is critical for plant growth and development (Peleg and Blumwald 2011). One necessary approach for more effective outcome from rice-pathogen interaction studies would be integration of omics approaches, such as combining transcriptomics with proteomics or metabolomics (Prathi et al 2018;Wang et al 2020) or combining proteomics with metabolomics (Karmakar et al 2019). Moreover, combining separate studies on specific stressor may serve as excellent approach, even though this may bring out some inconsistency.…”

“…Resultant proteins and metabolites in response to a common biotic stressor may belong to similar pathways, which will eventually increase the efficacy of outcome to get more detailed insight into the intricate cellular activities during rice responses to that stressor. For instance, two separate proteomics and metabolomics studies on rice response to leafroller insect (Cnaphalocrocis medinalis) suggest that the JA biosynthesis pathway related proteins and metabolites are critical for resistance (Cheah et al 2020;Wang et al 2020).…”

Cooperative herbivory between two important pests of rice

“…Since trypsin protease inhibitors (TPIs) serve as indicators of induced resistance in rice plants, especially against chewing herbivores such as SSB 35,36 , the analyses focused on expression profiles of TPIs-related genes among the four plant treatments. The expression of nine selected TPIs genes were validated by quantitative real-time PCR (qRT-PCR) analyses as previously described 70 . qRT-PCR was conducted on a Bio-RadCFX96 Touch Real-time PCR Detection System instrument (Bio-Rad, Hercules, CA, USA) using TransStart ® Top Green qPCR SuperMix (TransGen Biotech, Beijing, China).…”

RNA-Seq and Electrical Penetration Graph Revealed the Role of Grh1-Mediated Activation of Defense Mechanisms towards Green Rice Leafhopper (Nephotettix cincticeps Uhler) Resistance in Rice (Oryza sativa L.)

“…Among the plant hormones involved in the plant stress response mechanism against biotic stresses, salicylic acid (SA) and jasmonic acid (JA) have been shown to be predominant [ 21 ]. Under the same conditions, a transcriptional reprogramming within the cell takes place, which is followed by the accumulation of protein kinases, secondary metabolites, and changes in the photosynthetic process, among other cellular processes [ 22 ].…”