A Ubiquitously Expressed UDP-Glucosyltransferase, UGT74J1, Controls Basal Salicylic Acid Levels in Rice

Abstract

Salicylic acid (SA) is a phytohormone that regulates a variety of physiological and developmental processes, including disease resistance. SA is a key signaling component in the immune response of many plant species. However, the mechanism underlying SA-mediated immunity is obscure in rice (Oryza sativa). Prior analysis revealed a correlation between basal SA level and blast resistance in a range of rice varieties. This suggested that resistance might be improved by increasing basal SA level. Here, we identified a novel UDP-glucosyltransferase gene, UGT74J1, which is expressed ubiquitously throughout plant development. Mutants of UGT74J1 generated by genome editing accumulated high levels of SA under non-stressed conditions, indicating that UGT74J1 is a key enzyme for SA homeostasis in rice. Microarray analysis revealed that the ugt74j1 mutants constitutively overexpressed a set of pathogenesis-related (PR) genes. An inoculation assay demonstrated that these mutants had increased resistance against rice blast, but they also exhibited stunted growth phenotypes. To our knowledge, this is the first report of a rice mutant displaying SA overaccumulation.

Changes in the concentrations and transcripts for gibberellins and other hormones in a growing leaf and roots of wheat seedlings in response to water restriction

“…Notably, a UDP-glucosyltransferase gene UGT74J3 was strongly up-regulated by drought, while the more highly expressed UGT74H genes were down-regulated in the remaining leaf. In rice, these glucosyltransferases have been shown to conjugate SA and regulate its concentration [ 57 , 58 ]. While there was little uniform change in expression of jasmonate biosynthetic genes in response to drought, several genes encoding COI receptors, the JAZ signalling component and MYC transcription factors were up-regulated by drought in the leaf tissues (Fig.…”

Genome-Wide Analysis and Identification of UDP Glycosyltransferases Responsive to Chinese Wheat Mosaic Virus Resistance in Nicotiana benthamiana

“…Therefore, it is possible that these three UGT genes, particularly NbUGT12 , are involved in the flavonoid metabolism or other links in the phenylpropanoid metabolic pathway, which could affect plant growth and susceptibility to CWMV infection. Some UGTs are also involved in hormone pathways, such as JA, SA, and abscisic acid (ABA) [ 23 , 74 , 75 , 76 ], which are also related to plant resistance. For instance, it was discovered that aspirin (acetyl-SA) was resistant to tobacco mosaic virus in 1979, marking the first report of SA’s involvement in plant immunity [ 77 ].…”

“…For example, the overexpression of UGT74F2 in Arabidopsis thaliana reduced free SA levels and resistance to Pseudomonas syringae ( P. syringae ) infection; conversely, the knockout of UGT74F2 had the opposite effect [ 21 , 22 ]. The knockout of UGT74J1 in Oryza sativa resulted in increased SA levels and promoted resistance to Magnaporthe oryzae [ 23 ]. The disruption of the expression of methyl salicylate (MeSA)-specific UGT71C3 in Arabidopsis thaliana enhanced systemic acquired resistance to P. syringae by increasing MeSA and free SA levels [ 24 ].…”

Combined metabolomic and transcriptomic analysis reveals key components of OsCIPK17 overexpression improves drought tolerance in rice

“…In addition to monosaccharides, oligosaccharides, and polysaccharides, common glycosyl receptors include non-carbohydrates, such as proteins, lipids, antibiotics, sterols, phenols, terpenes, cyanohydrins, plant hormones, alkaloids, plant toxins, and exogenous substances ( Shimojima, 2011 ). These enzymes catalyze an array of substrates, playing vital roles in plant growth and development, metabolic regulation, detoxification of internal and external toxins, and synthesis and storage of secondary metabolites ( Liu et al., 2015 ; Wu et al., 2019 ; Tezuka et al., 2021 ). Through transcriptional and metabolic association analysis, we found that OsUGT79 is involved in multiple pathways.…”