OsGRAS23, a rice GRAS transcription factor gene, is involved in drought stress response through regulating expression of stress-responsive genes

Abstract

BackgroundDrought is a major abiotic stress factors that reduces agricultural productivity. GRAS transcription factors are plant-specific proteins that play diverse roles in plant development. However, the functions of a number of GRAS genes identified in rice are unknown, especially the GRAS genes related to rice drought resistance have not been characterized.ResultsIn this study, a novel GRAS transcription factor gene named OsGRAS23, which is located in a drought-resistant QTL interval on chromosome 4 of rice, was isolated. The expression of OsGRAS23 was induced by drought, NaCl, and jasmonic acid treatments. The OsGRAS23-GFP fused protein was localized in the nucleus of tobacco epidermal cells. A trans-activation assay in yeast cells demonstrated that the OsGRAS23 protein possessed a strong transcriptional activation activity. OsGRAS23-overexpressing rice plants showed improved drought resistance and oxidative stress tolerance as well as less H2O2 accumulation compared with the wild-type plants. Furthermore, microarray analysis showed that several anti-oxidation related genes were up-regulated in the OsGRAS23-overexpressing rice plants. The yeast one hybrid test indicated that OsGRAS23 could bind to the promoters of its potential target genes.ConclusionsOur results demonstrate that OsGRAS23 encodes a stress-responsive GRAS transcription factor and positively modulates rice drought tolerance via the induction of a number of stress-responsive genes.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-015-0532-3) contains supplementary material, which is available to authorized users.

DELAYED HEADING DATE1 interacts with OsHAP5C/D, delays flowering time and enhances yield in rice

“…Drought induces expression of OsABF1 , which directly binds to the downstream promoter of OsWARKY104 to activate its expression, which in turn, inhibits expression of Ehd1 and delays flowering (Zhang et al ., ). Previous studies have shown that the Lilium longiflorum SCR‐like (LISCL) subfamily proteins may be involved in the stress response, and recently, OsGRAS23, a member of the LISCL subfamily of rice, has been reported to be involved in drought response (Xu et al ., ). We observed that the dhd1 dhd1 l double mutant flowered earlier than WT and the dhd1 single mutant under drought and salt treatment.…”

“…Two Arabidopsis Phytochrome A signal transduction (AtPAT) subfamily members, Chitin-Inducible Gibberellin-Responsive 1 (CIGR1) and CIGR2, are responsive to N-acetyl-chitooligosaccharide elicitor and GA (Day et al, 2004). Recently, OsGRAS23 was reported to be involved in drought stress response by regulating expression of stress-responsive genes (Xu et al, 2015). However, GRAS proteins have not been reported in connection with heading date in rice.…”

Transcriptomic and Metabolomic Studies Disclose Key Metabolism Pathways Contributing to Well-maintained Photosynthesis under the Drought and the Consequent Drought-Tolerance in Rice

“…It is thus very difficult to enhance the drought-tolerance in rice by regulating a single gene. Instead, DEGs which could cause systematic effects have been preferred to be selected and applied in drought-tolerance breeding (Luo, 2010; Hu and Xiong, 2014), such as transcript factors (Hu et al, 2006; Jeong et al, 2012; Fang et al, 2015; Xu et al, 2015) and protein kinases (Saijo et al, 2000; Ning et al, 2010). Similarly, the metabolism of a metabolite commonly results from interactions of many genes and pathways.…”

“…We validated the measured levels of gene expression via the qPCR method, as previously described by Xu et al (2015). Nine genes, including known drought-resistance genes and several candidate genes were selected for validation (Table S4).…”

Identification of novel genes potentially involved in rice ( Oryza sativa L.) drought tolerance

“…(MONOCULM 1, a gene that is important in the control of rice tillering) (Li et al, 2003), SLR1 (the gene associated with the slender phenotype and its product is an intermediate of the GA signaling pathway) (Ikeda et al, 2001), SCR (SCARECROW, an essential gene for the asymmetric division of the cortex/endodermis progenitor cell in the root) (Kamiya et al, 2003), DLT (dwarf and lowtillering gene) (Tong et al, 2009), and OsGRAS19 , have been well characterized, while the functions of other rice GRAS genes are largely unknown (Xu et al, 2015). According to the report provided by Xu and coworkers (2015), OsGRAS23, a stress-responsive GRAS transcription factor, positively regulates the drought tolerance in rice through the induction of several stress-responsive genes.…”