Gene Expression and Proteomics Studies Suggest an Involvement of Multiple Pathways Under Day and Day–Night Combined Heat Stresses During Grain Filling in Wheat

Abstract

Recent weather fluctuations imposing heat stress at the time of wheat grain filling cause frequent losses in grain yield and quality. Field-based studies for understanding the effect of terminal heat stress on wheat are complicated by the effect of multiple confounding variables. In the present study, the effect of day and day–night combined heat stresses during the grain-filling stage was studied using gene expression and proteomics approaches. The gene expression analysis was performed by using real-time quantitative PCR (RT-qPCR). The expression of genes related to the starch biosynthetic pathway, starch transporters, transcription factors, and stress-responsive and storage proteins, at four different grain developmental stages, indicated the involvement of multiple pathways. Under the controlled conditions, their expression was observed until 28 days after anthesis (DAA). However, under the day stress and day–night stress, the expression of genes was initiated earlier and was observed until 14 DAA and 7 DAA, respectively. The protein profiles generated using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS/MS) showed a differential expression of the proteins belonging to multiple pathways that included the upregulation of proteins related to the translation, gliadins, and low-molecular-weight (LMW) glutenins and the downregulation of proteins related to the glycolysis, photosynthesis, defense, and high-molecular-weight (HMW) glutenins. Overall, the defense response to the day heat stress caused early gene expression and day–night heat stress caused suppression of gene expression by activating multiple pathways, which ultimately led to the reduction in grain-filling duration, grain weight, yield, and processing quality.

Gluten subfractions of wheat storage proteins are affected by high night temperature during grain formation

“…The sedimentation tests were done on the grains sampled at maturity. The gene expression analysis of the various fractions of gliadin and glutenin proteins was conducted on the pooled (superior and inferior) grain samples collected at 10 DAA as storage protein is majorly expressed approximately between 7 and 14 DAA under high temperatures (Chunduri et al, 2021).…”

Temperature‐smart plants: A new horizon with omics‐driven plant breeding

“…Wang et al (2021) reported 1,591 differentially abundant proteins (DAPs) related to stimuli response, structural molecule activity and transporter activity, catalytic activity, energy production and conversion, and carbohydrate transport and metabolism in two pepper varieties (heat‐tolerant 17CL30 and heat‐sensitive 05S180) upon HS exposure (40°C). In wheat under HS, Chunduri et al (2021) reported enhanced expression of DAPs involved in translation, gliadins, and low‐molecular‐weight glutenins and decreased expression of defense‐related, photosynthesis, glycolysis, and high‐molecular‐weight glutenins DAPs. Lettuce plants suffered early bolting within 8 days of HS (33°C), resulting in 93 DAPs, with 38 up‐regulated, such as HSP‐like proteins (XP_023757207.1, XP_023740399.1, and PLY74879.1), thaumatin‐like protein, rRNA 2′‐O‐methyl‐transferase fibrillarin‐like protein, GA‐related protein14‐like protein, and aldehyde dehydrogenase family 2 member B4, and 55 down‐regulated, such as the Calvin cycle protein CP12–3 and TsetseEP‐like protein (Hao et al, 2021).…”

Wheat Proteomics for Abiotic Stress Tolerance and Root System Architecture: Current Status and Future Prospects

“…The inhibition of protein synthesis (translation) under heat stress resulted from a reduction in aminoacyl tRNA synthetases. Recently, Chunduri et al [ 115 ] investigated the effect of day and day–night combined heat stresses during grain filling and revealed the upregulation of proteins belonging to multiple pathways, including gliadins, LMW glutenins, and proteins involved in translation. In contrast, the high-molecular-weight glutenins and proteins involved in glycolysis, photosynthesis and defense were downregulated.…”