Drought tolerance and proteomics studies of transgenic wheat containing the maize C4 phosphoenolpyruvate carboxylase (PEPC) gene

Abstract

Enhancing drought tolerance of crops has been a great challenge in crop improvement. Here, we report the maize phosphoenolpyruvate carboxylase (PEPC) gene was able to confer drought tolerance and increase grain yield in transgenic wheat (Triticum aestivum L.) plants. The improved of drought tolerance was associated with higher levels of proline, soluble sugar, soluble protein, and higher water use efficiency. The transgenic wheat plants had also a more extensive root system as well as increased photosynthetic capacity during stress treatments. The increased grain yield of the transgenic wheat was contributed by improved biomass, larger spike and grain numbers, and heavier 1000-grain weight under drought-stress conditions. Under non-stressed conditions, there were no significant increases in these of the measured traits except for photosynthetic rate when compared with parental wheat. Proteomic research showed that the expression levels of some proteins, including chlorophyll A-B binding protein and pyruvate, phosphate dikinase, which are related to photosynthesis, PAP fibrillin, which is involved in cytoskeleton synthesis, S-adenosylmethionine synthetase, which catalyzes methionine synthesis, were induced in the transgenic wheat under drought stress. Additionally, the expression of glutamine synthetase, which is involved in ammonia assimilation, was induced by drought stress in the wheat. Our study shows that PEPC can improve both stress tolerance and grain yield in wheat, demonstrating the efficacy of PEPC in crop improvement.

Early mannitol-triggered changes in the Arabidopsis leaf (phospho)proteome reveal growth regulators

“…This is in agreement with previous studies where it was shown that abiotic stresses can induce PEPC gene expression in wheat, A. thaliana , and sorghum (Echevarría et al , 2001; González et al , 2003; García-Mauriño et al , 2003; Sánchez et al , 2006). Moreover, recent studies demonstrated that the maize PEPC gene was able to confer drought tolerance and increase grain yield in transgenic wheat plants (Qin et al , 2016). Furthermore, in agreement with an earlier report on drought (Lawlor and Tezara, 2009), our data showed that photosynthesis-related proteins, such as PHOTOSYSTEM II SUBUNIT Q and PHOTOSYSTEM II SUBUNIT P, were down-regulated upon mannitol-induced stress, as were many chloroplast-located proteins.…”

Interactive Effects of Elevated [CO2] and Water Stress on Physiological Traits and Gene Expression during Vegetative Growth in Four Durum Wheat Genotypes

“…PEPC is a multifaceted key enzyme that in C 3 plants is linked to the provision of Krebs cycle intermediates, and its overexpression in transgenic wheat improved drought tolerance and grain yield (Qin et al, 2015). PEPC expression has not been widely studied during early growth in durum wheat plants.…”

Genome-wide Analysis of Phosphoenolpyruvate Carboxylase Gene Family and Their Response to Abiotic Stresses in Soybean

“…For example, an up-regulated PEPC expression in response to salinity or drought stress has been well documented in C 3 , C 4 and CAM plants678910. Meanwhile, overexpression of PEPC gene in transgenic plants enhanced their tolerance to drought or salt stress11, whereas knockdown of PEPC leading to increased sensitivity to osmotic stress12.…”