Unconventional splicing of wheat TabZIP60 confers heat tolerance in transgenic Arabidopsis

Abstract

Conditions that disrupt protein folding, such as heat stress, can overwhelm the capacity of cells to fold proteins, thus causing endoplasmic reticulum (ER) stress. In Arabidopsis thaliana and other plants, inositol-requiring enzyme-1 mediated unconventional splicing of bZIP60 plays a crucial role in the heat and ER stress responses. However, little is known about this pathway in wheat (Triticum aestivum), especially its importance in heat tolerance. Here, we found that heat stress induced upregulation and unconventional splicing of TabZIP60 occurred in wheat seedlings. Constitutive expression of the spliced form of TabZIP60 (TabZIP60s) enhanced heat tolerance in Arabidopsis, but overexpression of the unspliced form (TabZIP60u) did not. RNA-sequencing analysis revealed ER stress related genes involved in heat responses in TabZIP60s-overexpression transgenic Arabidopsis. Chromatin immunoprecipitation-qPCR showed that TabZIP60s directly binds to 17 target genes including AtbZIP60. Also, the 26S proteasome pathway post-translationally regulates TabZIP60s levels during heat stress responses. Our findings suggest that unconventional splicing of TabZIP60 could contribute to heat tolerance in transgenic plants by modulating the expression of ER stress-related genes.

The walnut transcription factor JrGRAS2 contributes to high temperature stress tolerance involving in Dof transcriptional regulation and HSP protein expression

“…9). The similar results here were observed in the plants overexpression of JrGSTTau1 that the transgenic plants accumulated less ROS, more biomass and higher activities of SOD, POD than WT plant under cold stress [50]; overexpression of the wheat F-Box protein gene TaFBA1 enhanced heat stress tolerance in transgenic tobacco owing to the growth inhibition was reduced and photosynthesis was increased as compared with those in WT plants [51]; Malus sieversii MsHsp16.9 is proved to be a protein chaperone that attenuate plant responses to severe stress via positively regulates antioxidant enzyme activity [52]. Therefore, we believe that JrGRAS2 is a vital HT stress responsive gene for walnut tree in temperature adaption regulation.…”

“…Plant TFs usually participate in stress response by regulating downstream related genes [50], for instance, unconventional splicing of wheat TabZIP60 could contribute to heat tolerance in transgenic plants by modulating the expression of ER stress-related genes [50]; Vitis amurensis GRAS TF VaPAT1 confers abiotic stress tolerance via up-regulate stress-related genes such as AtSIZ1 , AtCBF1 , AtATR1/MYB34 , AtMYC2 , AtCOR15A , AtRD29A and AtRD29B [53]; Tamarix eukaryotic translation initiation factor 1A ( eIF1A ) connected to the expression of stress-related genes, TOBLTP, GST , MnSOD , NtMPK9 , poxN1 and CDPK15 , in salt and drought stress response [54]. Since the HSP proteins were important HT stress-related members [6, 52, 55], the Arabidopsis HSP genes were identified from the TAIR database and analyzed in JrGRAS2 overexpression Arabidopsis plants, whose transcription were enhanced in S3, S7 and S8 compared to those in WT plants (Fig.…”

Reducing expression of a nitrate‐responsive bZIP transcription factor increases grain yield and N use in wheat

“…The expression of TabZIP60 is induced by exogenous ABA treatment in wheat (Figure B), as has been shown previously in wheat (Zhang et al ., ). Overexpression of TabZIP60 in Arabidopsis increases tolerance to multiple abiotic stress and the sensitivity to ABA (Geng et al ., ; Zhang et al ., ). These results indicate a role of TabZIP60 in ABA signalling and stress tolerance.…”

BrPP5.2 Overexpression Confers Heat Shock Tolerance in Transgenic Brassica rapa through Inherent Chaperone Activity, Induced Glucosinolate Biosynthesis, and Differential Regulation of Abiotic Stress Response Genes

“…Heat stress upregulated most HSR genes at the transcriptional level, which usually had opposite expression patterns under standard growth conditions. The overexpression of many of these HSR genes, such as DDF1 [ 27 ], ATHSFA2 [ 28 ], AT-HSFB2A [ 29 ], BIP3 [ 30 ], MIPS2 [ 31 ], HSP17.6II [ 32 ], HSP17.6B-CI [ 33 ], Hsp70b [ 34 ], HSP70 [ 35 ], and CYP71B2 [ 36 ], would facilitate improved tolerance to heat stress. Thus, we conclude that the overexpression of HSR genes during heat stress may contribute to BrPP5.2-mediated heat stress tolerance.…”