Roots are generally the critical drought sensors, but little is known about their molecular response to drought stress. We used the drought-tolerant soybean variety ‘Jiyu 47’ to investigate the differentially expressed proteins (DEPs) in soybean roots during the seedling stage based on the tandem mass tag (TMT) proteomics analysis. Various expression patterns were observed in a total of six physiological parameters. A total of 468 DEPs (144 up-regulated and 324 down-regulated) among a total of 8687 proteins were identified in response to drought stress in 24 h. The expression of DEPs was further validated based on quantitative real-time PCR of a total of five genes (i.e., GmGSH, GmGST1, GmGST2 k GmCAT, and Gm6PGD) involved in the glutathione biosynthesis. Results of enrichment analyses revealed a coordinated expression pattern of proteins involved in various cellular metabolisms responding to drought stress in soybean roots. Our results showed that drought stress caused significant alterations in the expression of proteins involved in several metabolic pathways in soybean roots, including carbohydrate metabolism, metabolism of the osmotic regulation substances, and antioxidant defense system (i.e., the glutathione metabolism). Increased production of reduced glutathione (GSH) enhanced the prevention of the damage caused by reactive oxygen species and the tolerance of the abiotic stress. The glutathione metabolism played a key role in modifying the antioxidant defense system in response to drought stress in soybean roots. Our proteomic study suggested that the soybean plants responded to drought stress by coordinating their protein expression during the vegetative stage, providing novel insights into the molecular mechanisms regulating the response to abiotic stress in plants.

ZAG2 has been identified as a maternally expressed imprinted gene in maize endosperm. Our study revealed that paternally inherited ZAG2 alleles were imprinted in maize endosperm and embryo at 14days after pollination (DAP), and consistently imprinted in endosperm at 10, 12, 16, 18, 20, 22, 24, 26, and 28 DAP in reciprocal crosses between B73 and Mo17. ZAG2 alleles were also imprinted in reciprocal crosses between Zheng 58 and Chang 7-2 and between Huang C and 178. ZAG2 alleles exhibited differential imprinting in hybrids of 178×Huang C and B73×Mo17, while in other hybrids ZAG2 alleles exhibited binary imprinting. The tissue-specific expression pattern of ZAG2 showed that ZAG2 was expressed at a high level in immature ears, suggesting that ZAG2 plays important roles in not only kernel but ear development

Anthocyanins are important pigments for flower color, determining the ornamental and economic values of horticultural plants. As a key enzyme in the biosynthesis of anthocyanidins, dihydroflavonol 4‐reductase (DFR) catalyzes the reduction of dihydroflavonols to generate the precursors for anthocyanidins (i.e., leucoanthocyanidins) and anthocyanins. To investigate the functions of DFRs in plants, we cloned the GlaDFR1 and GlaDFR2 genes from the petals of Gentiana lutea var. aurantiaca and transformed both genes into Nicotiana tabacum by Agrobacterium‐mediated leaf disc method. We further investigated the molecular and phenotypic characteristics of T1 generation transgenic tobacco plants selected based on the hygromycin resistance and verified by both PCR and semiquantitative real‐time PCR analyses. The phenotypic segregation was observed in the flower color of the transgenic tobacco plants, showing petals darker than those in the wild‐type (WT) plants. Results of high‐performance liquid chromatography (HPLC) analysis showed that the contents of gentiocyanin derivatives were decreased in the petals of transgenic plants in comparison to those of WT plants. Ours results revealed the molecular functions of GlaDFR1 and GlaDFR2 in the formation of coloration, providing solid theoretical foundation and candidate genes for further genetic improvement in flower color of plants.

Phospholipid N-methyltransferase (PLMT) plays an important role in the synthesis of phosphatidylcholine (PtdCho). The aim of this study was to characterize the molecular properties of GmPLMT and the expression of soybean GmPLMT and its effects on the production of lipid metabolites. Results showed that GmPLMT composed of mainly α-helix was a hydrophobic and transmembrane protein. In soybean leaves, GmPLMT was highly expressed during seedling and flowering stages. In transgenic Arabidopsis thaliana, the highest and lowest expression levels of GmPLMT were detected at flowering and maturity stages, respectively. The total phospholipid contents in soybean grains were decreased from 7.2% (35 days after flowering) to 4.8% (55 days after flowering) and then increased to 7.0% (75 days after flowering). The contents of PtdCho showed a similar pattern to that of total phospholipids. In transgenic A. thaliana seeds, the contents of total phospholipids and PtdCho were significantly increased. Significantly positive correlations were revealed between expression of GmPLMT and contents of both PtdCho and crude fats, and between the contents of PtdCho and both linoleic acid and linolenic acid, suggesting that increased expression of GmPLMT improved the production of lipid metabolites. This study provided solid experimental evidence for further improvement of soybean quality based on GmPLMT in the molecular breeding of soybeans.