Role of WRKY transcription factors in plant defense against lepidopteran insect herbivores: an overview

Abstract

Plants, in nature are challenged by various environmental stresses (both biotic and abiotic), which distort the plant growth, development and crop yield. A wide range of insect herbivores attack plants across the globe, throughout the year, causing huge loss to the productivity of crop species. Being sessile, the plants respond to the crisis using a wide range of defense responsive elements which at the transcriptional level, includes the transcription factors, like WRKY, NAC, AP2/ERF, MYB, MYC, bZIP, bHLH and others. Increasing evidences suggest a pivotal role of WRKY TFs in the regulation of plant defense response against herbivory in Arabidopsis and other important crop plants. Unlike pathogenic attack, very limited information is available on the role of different WRKYs in herbivore-plant interaction. In this review, we will thus majorly focus on the role of WRKY transcription factors and its regulation in response to herbivore attack while summarizing the recent developments from the field of transcriptional, post-transcriptional and epigenetic regulation of WRKYs in response to herbivory attack with the prospects for future implementation in research.

Transcriptomic Analysis of Tobacco Plants in Response to Whitefly Infection

“…TFs are key components of plant signaling networks that regulate gene expression in response to various factors, including plant growth, development, and biotic and abiotic stresses [ 34 , 35 ]. In our study, several TFs, including WRKY TFs and ERFs, were identified among the DEGs.…”

Influence of plant defense signaling and innate insect metabolic differences to the overall performance of fall armyworm (Spodoptera frugiperda) corn and rice strains on maize as a host

“…The very significant increase of ∼6.9 fold in the transcript of the corresponding maize WRKY( ZmWRKY56 ) subject to corn strain herbivory is in line with the relatively lower JA signaling in maize leaves subject to corn strain herbivory compared to rice strain herbivory. Finally, the Arabidopsis AtWRKY33 has been shown to positively regulate JA- and ET-mediated defenses (Kundu and Vadassery 2021; Zheng et al 2006) with a well-supported role in wounding and herbivory. An up-regulation of the maize homolog ZmWRKY92 during rice strain herbivory over corn strain herbivory is in accordance with the increased JA defense response towards the rice strain.…”

Transcriptomics and Antioxidant Analysis of Two Chinese Chestnut (Castanea mollissima BL.) Varieties Provides New Insights Into the Mechanisms of Resistance to Gall Wasp Dryocosmus kuriphilus Infestation

“…The functional category of "transcription factors" was significantly enriched in the transcript expression profiles of many biotic defense-related transcriptomics comparative studies, and the WRKY TF class is widely reported in the context of biotic and abiotic stress responses (Bai et al, 2018). Induction of the expression of WRKY TF genes in response to herbivory was observed in N. attenuata (Skibbe et al, 2008), rice (Akagi et al, 2014), and other plants (Kundu and Vadassery, 2021), which affected the biosynthesis of defensive secondary metabolites or by reprogramming the expression of associated pathway genes. Apart from WRKY TFs, other classes of TFs associated with herbivory infestations have also been widely reported, for example, in rice, leaf, and phloem feeding by brown planthopper (BPH) induced the transcript levels of genes encoding transcription factors of the AP2/ERF, MYB, bZIP, and bHLH families (Li et al, 2021).…”