Diacylglycerol kinase and associated lipid mediators modulate rice root architecture

Abstract

Summary Diacylglycerol kinase (DGK) phosphorylates diacylglycerol (DAG) to generate phosphatidic acid (PA), and both DAG and PA are lipid mediators in the cell. Here we show that DGK1 in rice (Oryza sativa) plays important roles in root growth and development. Two independent OsDGK1‐knockout (dgk1) lines exhibited a higher density of lateral roots (LRs) and thinner seminal roots (SRs), whereas OsDGK1‐overexpressing plants displayed a lower LR density and thicker SRs than wild‐type (WT) plants. Overexpression of OsDGK1 led to a decline in the DGK substrate DAG whereas specific PA species decreased in dgk1 roots. Supplementation of DAG to OsDGK1‐overexpressing seedlings restored the LR density and SR thickness whereas application of PA to dgk1 seedlings restored the LR density and SR thickness to those of the WT. In addition, treatment of rice seedlings with the DGK inhibitor R59022 increased the level of DAG and decreased PA, which also restored the root phenotype of OsDGK1‐overexpressing seedlings close to that of the WT. Together, these results indicate that DGK1 and associated lipid mediators modulate rice root architecture; DAG promotes LR formation and suppresses SR growth whereas PA suppresses LR number and promotes SR thickness.

Plant lipid metabolism in susceptible and tolerant soybean (Glycine max) cultivars in response to Phytophthora sojae colonization and infection

“…Studies have demonstrated that signaling enzymes, diacylglycerol kinases (DGKs) play important roles in response to biotic stress by phosphorylating DG to synthesis PA (Fig. 9) and both PA and DG are lipid mediators during physiological process (Yuan et al 2019). Our findings from this study demonstrate that lipid metabolism and signalling possibly involving DG could play a significant role in pathogen resistance in the tolerant soybean cultivar.…”

Plant lipid metabolism in response to Phytophthora sojae infection in susceptible and tolerant soybean cultivars

“…Studies have demonstrated that signaling enzymes, diacylglycerol kinases (DGKs) play important roles in response to biotic stress by phosphorylating DG to synthesis PA (Fig. 9) and both PA and DG are lipid mediators during physiological process 60 . Our findings from this study demonstrate that lipid metabolism and signalling possibly involving DG could play a significant role in pathogen resistance in the tolerant soybean cultivar.…”

Genomic profiling and expression analysis of the diacylglycerol kinase gene family in heterologous hexaploid wheat

“…TaDGK2 and 6 had higher transcript levels in all organ, especially in roots. The closest ortholog to TaDGK2 is OsDGK1 in rice, which is also highly expressed in roots and affects rice lateral root development and seminal root/ crown root growth [16]. The transcripts of TaDGK7 were di cult to detect, both among tissues/organs and under hormone/stress treatment conditions, which might be owing to its exceptionally long fth intron (Fig.…”

“…In Arabidopsis, AtDGK7 is expressed ubiquitously, especially in owers and young seedlings [7]. OsDGK1 is intensively expressed in roots system, and modulates the growth and development of roots, which is associated with lipid mediators that control rice root architecture [16].…”