Two TGA Transcription Factor Members from Hyper-Susceptible Soybean Exhibiting Significant Basal Resistance to Soybean mosaic virus

Abstract

TGA transcription factors (TFs) exhibit basal resistance in Arabidopsis, but susceptibility to a pathogen attack in tomatoes; however, their roles in soybean (Glycine max) to Soybean mosaic virus (SMV) are unknown. In this study, 27 TGA genes were isolated from a SMV hyper-susceptible soybean NN1138-2, designated GmTGA1~GmTGA27, which were clustered into seven phylogenetic groups. The expression profiles of GmTGAs showed that the highly expressed genes were mainly in Groups I, II, and VII under non-induction conditions, while out of the 27 GmTGAs, 19 responded to SMV-induction. Interestingly, in further transient N. benthamiana-SMV pathosystem assay, all the 19 GmTGAs overexpressed did not promote SMV infection in inoculated leaves, but they exhibited basal resistance except one without function. Among the 18 functional ones, GmTGA8 and GmTGA19, with similar motif distribution, nuclear localization sequence and interaction proteins, showed a rapid response to SMV infection and performed better than the others in inhibiting SMV multiplication. This finding suggested that GmTGA TFs may support basal resistance to SMV even from a hyper-susceptible source. What the mechanism of the genes (GmTGA8, GmTGA19, etc.) with basal resistance to SMV is and what their potential for the future improvement of resistance to SMV in soybeans is, are to be explored.

A Genome-Wide Analysis of StTGA Genes Reveals the Critical Role in Enhanced Bacterial Wilt Tolerance in Potato During Ralstonia solanacearum Infection

“…The results indicated that the StTGA family is conserved in the evolutionary history with the TGA TFs orthologs of other plants. This result corresponds well with previous observations in many plant species (Moon et al, 2018;Ullah et al, 2019;Jiang et al, 2021).…”

“…The expression heat map demonstrated that the TGA TFs may have played significant and complex roles in potato ( Figure 4 ), which was reflected in at least two aspects. First, the RNA-seq data-based heat map showed that the expression of most of the StTGAs was significantly different under abiotic/biotic stresses, which was consistent with previous studies ( Jiang et al, 2021 ). Second, the same gene showed different or even opposite expression patterns under different stresses or in different tissues.…”

“…TGA TFs have been reported to function in various biological processes in plants ( Jiang et al, 2021 ; Martins et al, 2022 ) and members of the TGA TFs play crucial roles in response to microbial pathogens in plants, such as Arabidopsis, soybean, rice, and tobacco ( Pontier et al, 2002 ; Van et al, 2011 ; Moon et al, 2018 ; Ullah et al, 2019 ). There is a lack of reports on the potential link between TGA TFs and resistance to bacterial wilt caused by R. solanacearum in potato.…”

Genome-wide identification of the TGA genes in common bean (Phaseolus vulgaris) and revealing their functions in response to Fusarium oxysporum f. sp. phaseoli infection

“…TGA2 , TGA5 , and TGA6 make up Group II; they are connected and have functional redundancy. TGA3 and TGA7 make up Group III, TGA9 and TGA10 make up Group IV, and TGA8 is the solitary member of Group V. Among these identified TGAs , TGA1-TGA7 has been proven to interact with key resistance-related genes such as NPR1 , and participate in multiple signal regulation pathways in plants to improve plant biotic and abiotic stress resistance ( Johnson et al, 2001 ; Choi et al, 2004 ; Thurow et al, 2005 ; Jiang et al, 2021 ; Liu et al, 2022 ). In addition to Arabidopsis and tobacco, TGA has been identified in a variety of plants related to disease resistance, such as the TGA gene in soybean responds to mosaic virus, kiwifruit TGAs plays a role in the process of Pseudomonas syringae pv.…”

“…In addition to Arabidopsis and tobacco, TGA has been identified in a variety of plants related to disease resistance, such as the TGA gene in soybean responds to mosaic virus, kiwifruit TGAs plays a role in the process of Pseudomonas syringae pv. Actinidiae ( Psa ) infection ( Jiang et al, 2021 ; Liu et al, 2022 ). In Brachypodium distachyon , the TGA -promoted transcription of SA-inducible PR1 is orchestrated by the activator BdNPR2 and the repressor BdNPR1 to enforce immune resistance ( Shimizu et al, 2022 ).…”