Arabidopsis Transcription Factor MYB102 Increases Plant Susceptibility to Aphids by Substantial Activation of Ethylene Biosynthesis

Abstract

Induction of ethylene biosynthesis by aphids increases the susceptibility of several plant species to aphids. Recent studies have indicated that some MYB transcription factors regulate the phloem-based defense against aphid infestation by modulating ethylene (ET) signaling. Arabidopsis MYB102 has previously been shown to be induced by wound signaling and regulate defense response against chewing insects. However, it remains unclear whether Arabidopsis MYB102 takes part in the defense response of plants to aphids. Here, we investigated the function of MYB102 in the response of Arabidopsis to aphid infestation. Arabidopsis MYB102 was primarily expressed in vascular tissues, and its transcription was remarkably induced by green peach aphids (GPA; Myzus persicae). The results of RNA-Sequencing revealed that overexpression of MYB102 in Arabidopsis promoted ET biosynthesis by upregulation of some 1-aminocyclopropane-1-carboxylate synthase (ACS) genes, which are rate-limiting enzymes of the ET-synthetic pathway. Enhanced ET levels led to reduced Arabidopsis resistance to GPA. Furthermore, dominant suppression of MYB102 inhibited aphid-induced increase of ET levels in Arabidopsis. In agreement with a negative regulatory role for ET in aphid defense responses, the MYB102-overexpressing lines were more susceptible to GPA than wild-type (WT) plants. Overexpression of MYB102 in Arabidopsis obviously repressed aphid-induced callose deposition. Conversely, overexpression of MYB102 failed to increase aphid susceptibility in both the ET-insensitive mutants and plants treated with inhibitors of ET signaling pathways, demonstrating that the ET was critical for promoting aphid performance conferred by overexpression of MYB102. Collectively, our findings indicate that the Arabidopsis MYB102 increases host susceptibility to GPA through the ET-dependent signaling pathways.

Introgression of resistance to Rhopalosiphum padi L. from wild barley into cultivated barley facilitated by doubled haploid and molecular marker techniques

“…In wheat, ethylene signaling and certain MYB transcription factors contribute to resistance to the aphid Sitobion avenae via aphid-induced phloem occlusion (Zhai et al 2017 ). On the contrary, MYB102 activates ethylene biosynthesis and promotes performance of Myzus persicae , the aphid species most commonly studied in interactions with A. thaliana (Zhu et al 2018 ). Another transcript in the barley 0–6-cM 2HS region belongs to the NRT1 PTR family potentially involved in plant hormonal transport (Chiba et al 2015 ).…”

Transcription Factors in Plant Stress Responses: Challenges and Potential for Sugarcane Improvement

“…In addition to abiotic stress response, MYB TFs were also observed to be involved against biotic stresses. In Arabidopsis, AtMYB102 was observed to enhance susceptibility against GPA (green-peach aphids) infestation [122]. AtMYB96 acts as important molecular link between SA and ABA crosstalk, through which it can enhance the resistance against pathogens in Arabidopsis [123].…”

Selection and validation of reference genes for measuring gene expression in Toona ciliata under different experimental conditions by quantitative real-time PCR analysis

“…MYB proteins, which constitute one of the largest family of transcription factors in plants, play important roles in plant growth and development, biotic and abiotic stress responses, and circadian rhythm regulation [30,31]. For example, the R2R3 MYB transcription factor MdMYB30 modulates plant resistance against pathogens, and Arabidopsis transcription factor MYB102 increases plant susceptibility to aphids [32,33]. Our research provided the best reference genes for RT-qPCR analysis of T. ciliata under different conditions, laying a foundation for studying molecular mechanisms in T. ciliata through gene expression analysis.…”