TaSINA2B, interacting with TaSINA1D, positively regulates drought tolerance and root growth in wheat (Triticum aestivum L.)

Abstract

Wheat (Triticum aestivum L.) is an important food crop mainly grown in arid and semiarid regions worldwide, whose productivity is severely limited by drought stress. Although various E3 ubiquitin (Ub) ligases regulate drought stress, only a few SINA‐type E3 Ub ligases are known to participate in such responses. Herein, we identified and cloned 15 TaSINAs from wheat. The transcription level of TaSINA2B was highly induced by drought, osmotic and abscisic acid treatments. Two‐type promoters of TaSINA2B were found in 192 wheat accessions; furthermore wheat accessions with promoter TaSINA2BII showed a considerably higher level of drought tolerance and gene expression levels than those characterizing accessions with promoter TaSINA2BI that was mainly caused by a 64 bp insertion in its promoter. Enhanced drought tolerance of TaSINA2B‐overexpressing (OE) transgenic wheat lines was found to be associated with root growth promotion. Further, an interaction between TaSINA2B and TaSINA1D was detected through yeast two‐hybrid and bimolecular fluorescence complementation assays. And TaSINA1D‐OE transgenic wheat lines showed similar drought tolerance and root growth phenotype to those observed when TaSINA2B was overexpressed. Therefore, the variation of TaSINA2B promoter contributed to the drought stress regulation, while TaSINA2B, interacting with TaSINA1D, positively regulated drought tolerance by promoting root growth.

Physiological and RNA-Seq Analyses on Exogenous Strigolactones Alleviating Drought by Improving Antioxidation and Photosynthesis in Wheat (Triticum aestivum L.)

“…According to a classical model, the chaperone-associated E3 ubiquitin ligase CHIP ubiquitinates soluble misfolded proteins associated with chaperone molecules and targets them for degradation through the 26S proteasome during stress [52]. The overexpression of E3 ubiquitin ligases, HSF, HSP, and DnaJ has been demonstrated to enhance root length, chlorophyll content, and antioxidant enzyme activity in transgenic plants, but reduce the production of MDA and ROS under stress [53][54][55][56][57]. In this study, several metabolic pathways were enriched, including "response to misfolded protein", "protein stabilization", "misfolded protein binding", "ubiquitin protein ligase activity", "ubiquitin-like protein ligase activity", "ubiquitin-like protein transferase activity", and "ubiquitin-protein transferase activity" (Figures 4, 5 and S8-S11).…”

Genome-Wide and Transcriptome-Wide Association Analysis Identifies qRS-6D and Its Candidate Genes Regulating Root Development of Wheat Seedlings

“…Multiple studies have also indicated that genes controlling wheat root development can enhance its resistance to abiotic stress. For example, TaSINA2B [25] and TaOPRIII [18] enhance drought resistance by regulating the root length and lateral root development; TaANR1 and TaMAD25 enhance wheat nitrogen uptake and drought resistance by increasing the primary root length [26]; and TaSWN enhances wheat adaptation to lownitrogen environments by promoting root development [27]. In our previous study, we cloned several root development-related genes with a genome-wide association study (GWAS), including TaFMO1-5B, which regulates the total root length and surface area [28]; the "Green Revolution" allele Rht-D1b (reduced height-D1b), which significantly increases wheat root systems [29]; and TaGW2-6B (grain width2-6B), whose mutants show enlarged root systems [30].…”