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Wheat WAG-1 is a C-class MADS-box gene, which is orthologous to AGAMOUS in Arabidopsis. In this study, we report the cloning, characterization, and expression patterns of WAG-1 in the pistillody mutant HTS-1 and its sib-line CSTP. The cDNA of WAG-1 was found to be 765 bp in length, which was equal to the length of its open reading frame, encoding 254 amino acids. The location of WAG-1 revealed that it has three homologous genes from the short arm of chromosome 1A, 1B, and 1D. Their genomic sequences were determined to be 5864, 6454, and 6447 bp long, respectively, and possessed seven exons and six introns. Young spikes from HTS-1 contained higher levels of WAG-1 transcript than did those from CSTP, and the transcript levels in the young spikes (7-10 mm in length) of HTS-1 increased 3.3-fold relative to those of the CSTP line. The transcript level in the pistil and pistil-like stamens of HTS-1 was over 2-fold higher than that in the stamens of CSTP, and expression in the pistil-like stamens of HTS-1 was slightly higher than that in its pistils. These data provide a basis for future research into the function of WAG-1, and offer further insight into the molecular mechanism of the pistillody mutation in common wheat.

Wheat (Triticum aestivum L.) is one of the major grain crops, and heat stress adversely affects wheat production in many regions of the world. Previously, we found a heat-responsive gene named Lipid Transfer Protein 3 (TaLTP3) in wheat. TaLTP3 was deduced to be regulated by cold, ABA, MeJA, Auxin and oxidative stress according to cis-acting motifs in its promoter sequences. In this study, we show that TaLTP3 is responsive to prolonged water deficit, salt or ABA treatment in wheat seedlings. Also, TaLTP3 accumulation was observed after the plant suffered from heat stress both at the seedling and the grain-filling stages. TaLTP3 protein was localized in the cell membrane and cytoplasm of tobacco epidermal cells. Overexpression of TaLTP3 in yeast imparted tolerance to heat stress compared to cells expressing the vector alone. Most importantly, transgenic Arabidopsis plants engineered to overexpress TaLTP3 showed higher thermotolerance than control plants at the seedling stage. Further investigation indicated that transgenic lines decreased H₂O₂ accumulation and membrane injury under heat stress. Taken together, our results demonstrate that TaLTP3 confers heat stress tolerance possibly through reactive oxygen species (ROS) scavenging., (Copyright © 2014. Published by Elsevier B.V.)

Comparative studies of chloroplast proteome on different developmental stage (seeding, tillering, shooting, booting stage) of leaves have been made in isoplamic allonuclear male-sterile lines Nongda 3237A, Xiaoyan No.6 A and their maintainer lines by 2D-PAGE. The results indicated that no obvious differences were found in chloroplast proteome between Nongda 3237A, Nongda 3237B, Xiaoyan No.6A, Xiaoyan No.6B at different developmental stages of leaves. Differences were found just at booting stage in Xiaoyan No.6A and its maintainer lines. Obvious differences, however, were observed in chloroplast proteome between isoplasmic allonuclear male-sterile lines Nongda 3237A and Xiaoyan No.6A. For instance,2 protein spots (pl5.4/34kDa, pl5.4/32kDa) at seedling stage,6 protein spots (pl5.4/80kDa, pl5.4/65kDa, pl5.4/60kDa, pl5.4/48kDa, pI5.4/40kDa, pI5.4/35kDa) at booting stage were present in Xiaoyan No.6A and absent in Nongda 3237A. pl6.3/18kDa was present at seedling stage in Nongda 3237A and absent in Xiaoyan No. 6A. pI6.8/28kDa protein spot revealed the developmental changes. It was present in leaves at seedling, tillering, shooting stages and absent at flowering stage in Nongda 3237A. No development changes of the protein spot were observed in Xiaoyan No.6A. These experiment results demonstrated that it was possible chloroplast proteome wasn't relative to the cytoplasmic male-sterile characteristics. But nuclear background in male -sterile lines can obviously affect chloroplast protein composition. Distant relative on nuclear-cytoplasmic has larger differences on chloroplast proteome than close relative on nuclear-cytoplasmic in CMS.

Previous studies have shown that heterosis is associated with differential gene expression between hybrids and their parents. In this study, we performed a screen for genes that are differentially expressed between wheat hybrids and their parents in jointing-stage leaves and flag leaves using the differential display technique. Twenty-four differentially expressed cDNA were cloned and sequenced, and their expression patterns were confirmed by reverse-Northern blotting. Sequence analysis and database searches revealed that among the genes that showed differential expression between hybrid and parents were transcription factor genes and genes involved in metabolism, signal transduction, disease resistance, and retrotransposons. These results indicate that hybridization between two parental lines can cause changes in the expression of a variety of genes, and it is concluded that the altered pattern of gene expression in the hybrid may be responsible for the observed heterosis.