Expression of Thioredoxin/Thioredoxin Reductase System Genes in Aphid-Challenged Maize Seedlings

Abstract

Thioredoxins (Trxs) and thioredoxin reductases (TrxRs) encompass a highly complex network involved in sustaining thiol-based redox homeostasis in plant tissues. The purpose of the study was to gain a new insight into transcriptional reprogramming of the several genes involved in functioning of Trx/TrxR system in maize (Zea mays L.) seedlings, exposed to the bird cherry-oat aphid (Rhopalosiphum padi L.) or the rose-grass aphid (Metopolophium dirhodum Walk.) infestation. The biotests were performed on two maize genotypes (susceptible Złota Karłowa and relatively resistant Waza). The application of real-time qRT-PCR technique allowed to identify a molecular mechanism triggered in more resistant maize plants, linked to upregulation of thioredoxins-encoding genes (Trx-f, Trx-h, Trx-m, Trx-x) and thioredoxin reductase genes (Ftr1, Trxr2). Significant enhancement of TrxR activity in aphid-infested Waza seedlings was also demonstrated. Furthermore, we used an electrical penetration graph (EPG) recordings of M. dirhodum stylet activities in seedlings of the two studied maize varieties. Duration of phloem phase (E1 and E2 models) of rose-grass aphids was about three times longer while feeding in Waza plants, compared to Złota Karłowa cv. The role of activation of Trx/TrxR system in maintaining redox balance and counteracting oxidative-induced damages of macromolecules in aphid-stressed maize plants is discussed.

Identification and characterization of Prx5 and Prx6 in Chilo suppressalis in response to environmental stress

“…Fortunately, insect Prxs and thioredoxin reductase (Trx) provide the functions of GPx and GR, respectively (Bauer et al, 2003; Couto et al, 2016; Dias et al, 2016). Like Trx, Prx is involved in cellular redox homeostasis regulation and helps to ameliorate the increased oxidative stress resulting from environmental stress, such as pesticides and extreme temperatures (Sytykiewicz et al, 2020). In fact, the antioxidative activity of insect Prxs has an indispensable function in the protection against ROS‐mediated toxicity, especially in B. mori and D. melanogaster (Wang et al, 2016a).…”

Genome-wide identification of foxtail millet’s TRX family and a functional analysis of SiNRX1 in response to drought and salt stresses in transgenic Arabidopsis

“…To date, the TRX family has been identified in Arabidopsis thaliana , rice ( Oryza sativa ) and wheat ( Triticum aestivum L.) ( Nuruzzaman et al, 2008 ; Nuruzzaman et al, 2012 ; Chibani et al, 2021 ; Bhurta et al, 2022 ). Numerous TRX types have been found to integrate gene expression and metabolic pathways, regulate various physiological processes (such as seed germination, seedling growth and flowering), and facilitate stress tolerance and defense responses to external stimuli in a wide number of studies ( Apel and Hirt, 2004 ; Meyer et al, 2005 ; Richter et al, 2018 ; Nikkanen and Rintamäki, 2019 ; Jing et al, 2020 ; Nietzel et al, 2020 ; Sytykiewicz et al, 2020 ). These findings imply that TRXs play significant roles in plant growth and development as well as stress tolerance.…”