Genome-wide identification and comparative analysis of diacylglycerol kinase (DGK) gene family and their expression profiling in Brassica napus under abiotic stress

Abstract

Background Diacylglycerol kinases (DGKs) are signaling enzymes that play pivotal roles in response to abiotic and biotic stresses by phosphorylating diacylglycerol (DAG) to form phosphatidic acid (PA). However, no comprehensive analysis of the DGK gene family had previously been reported in B. napus and its diploid progenitors (B. rapa and B. oleracea). Results In present study, we identified 21, 10, and 11 DGK genes from B. napus, B. rapa, and B. oleracea, respectively, which all contained conserved catalytic domain and were further divided into three clusters. Molecular evolutionary analysis showed that speciation and whole-genome triplication (WGT) was critical for the divergence of duplicated DGK genes. RNA-seq transcriptome data revealed that, with the exception of BnaDGK4 and BnaDGK6, BnaDGK genes have divergent expression patterns in most tissues. Furthermore, some DGK genes were upregulated or downregulated in response to hormone treatment and metal ion (arsenic and cadmium) stress. Quantitative real-time PCR analysis revealed that different BnaDGK genes contribute to seed oil content. Conclusions Together, our results indicate that DGK genes have diverse roles in plant growth and development, hormone response, and metal ion stress, and in determining seed oil content, and lay a foundation for further elucidating the roles of DGKs in Brassica species.

Genome-Wide Identification of the DGK Gene Family in Kiwifruit (Actinidia valvata Dunn) and Expression Analysis of Their Responses to Waterlogging Stress

“…Diverse gene function is affected significantly by the cis-element located in the promoter regions. Previous studies have reported that cis-elements on the promoters of DGKs are associated with multiple stresses such as drought, cold stress and wound stress and hormone responses such as ABA, SA and MeJA [16][17][18]21,22]. Some of the predictions were confirmed by the expression analysis.…”

“…In this study, we identified 18 AvDGK members within the Actinidia valvata genome which were located on 18 different chromosomes. The number of AvDGK genes identified in Actinidia valvata genome was relatively higher than the number found in Arabidopsis thaliana (7 AtDGKs) [14], in Zea mays (7 ZmDGKs) [21], in Malus domestica (8 MdDGKs) [19] and in Populus trichocarpa (7 PtDGKs) [22], but less than those in Triticum aestivum (24 TaDGKs) [18] and in Brassica napus (21 BnaDGKs) [17], which may be due to the differences in the size of the genome. The AvDGKs encoded proteins ranging from 456~734 amino acids, and these proteins were subcellularly located in the nucleus, chloroplast and cytoplasm.…”

“…DGKs are a widespread family of enzymes in most multicellular organisms. Members of DGK gene family have been identified in various plant species, including Arabidopsis thaliana [14], Oryza sativa [15], Phaseolus vulgaris [16], Brassica napus [17], Triticum aestivum [18], Malus domestica [19], Glycine max [20], Zea mays [21], and Populus trichocarpa [22]. In plants, DGKs are grouped into three phylogenetic clusters based on their domain structures and sequence similarities [13,14].…”

Transcriptome Co-expression Network Analysis Identifies Key Genes Regulating Conchosporangia Maturation of Pyropia haitanensis

“…Thus, PhDGK1 is the same type of enzyme as DGK2 and DGK7, which are known to be involved in plant growth and development. For example, MpDGK2 from Malus prunifolia was shown to affect the growth and tolerance of Arabidopsis via regulating H 2 O 2 homeostasis and antioxidant enzyme activity ( Tang et al, 2020 ). In addition, the content of PA, an important signaling molecule, was decreased in an AtDGK2- knockdown mutant, resulting in deceased pollen viability and pollen germination ( Angkawijaya et al, 2020 ).…”

Effects of repeated drought stress on the physiological characteristics and lipid metabolism of Bombax ceiba L. during subsequent drought and heat stresses

“…PA is produced through the phosphorylation of DAG or the hydrolysis of phospholipids and its synthesis can be induced by many types of stresses including chilling, freezing, drought and salinity [15,[53][54][55]. According to the maintenance of other lipid classes, the accumulation of PA in the plants subjected to D3 treatment may have resulted from the conversion of DAG, whose levels were also enhanced in this treatment [56]. As DAG can be further phosphorylated by DAG kinases to generate PA [57], its role in plants remains elusive [43].…”