Project description:The present study quantifies the transcriptomes of wild-type and transgenic Ubi::OsYHB rice seedlings (in the genetic background of Oryza sativa ssp. japonica CV Nipponbare) grown in the dark or under continous red light (Rc, at 50 µmol m-2 s-1) conditions. Overall design: WT (Nipponbare cultivar; Nip) and Ubi::OsYHB/Nip transgenic seedlings were grown at 28°C for 5 days in darkness or under continuous red light at 50 µmol m-2 s-1 (Rc50). Seedlings were harvested in subjective morning, immediately frozen in liquid nitrogen and strored at -80°C until RNA extraction. The expression of OsYHB is driven by the maize Ubiquitin promoter. Two biological replicates for each treatment. Two independent, genetically single-insertion, homozygous Ubi::OsYHB/Nip lines (#1 and # 9, with determined 41- and 23-fold overexpression levels of OsYHB in comparison to the wild-type control, respectively) were used. GeneChip 3' IVT Express Kit (Affymetrix) was used to synthesize and label aRNA.
Project description:BACKGROUND:The rice receptor kinase XA21 confers robust resistance to the bacterial pathogen Xanthomonas oryzaepv. oryzae(Xoo). We previously reported that XA21 is cleaved in transgenic plants overexpressing XA21 with a GFP tag (Ubi-XA21-GFP) and that the released C-terminal domain is localized to the nucleus. XA21 carries a predicted nuclear localization sequence (NLS) that directs the C-terminal domain to the nucleus in transient assays, whereas alanine substitutions in the NLS disrupt the nuclear localization. METHODS:To determine if the predicted NLS is required for XA21-mediated immunity in planta, we generated transgenic plants overexpressing an XA21 variant carrying the NLS with the same alanine substitutions (Ubi-XA21nls-GFP). RESULTS:Ubi-XA21nls-GFP plants displayed slightly longer lesion lengths, higher Xoobacterial populations after inoculation and lower levels of reactive oxygen species production compared with the Ubi-XA21-GFP control plants. However, the Ubi-XA21nls-GFP plants express lower levels of protein than that observed in Ubi-XA21-GFP. DISCUSSION:These results demonstrate that the predicted NLS is not required for XA21-mediated immunity.
Project description:We analyzed the transcriptomic profile of EFR:XA21:GFP rice lines treated with elf18 to identify genes differentially regulated during this response. We sequenced cDNA from EFR:XA21:GFP leaves treated with 500 nM elf18 for 0.5, 1, 3, 6, and 12 h. We also included untreated EFR:XA21:GFP and Kitaake as controls. Note: All samples in SRA were assigned the same sample accession (SRS843490). This is incorrect as there are different samples, hence â??Source Nameâ?? was replaced with new values. Comment[ENA_SAMPLE] contains the original SRA sample accessions.
Project description:As higher plants are sessile organisms, they are unable to move to more favorable places; thus, they have developed the ability to survive under potentially detrimental conditions. Ubiquitination is a crucial post-translational protein modification and participates in abiotic stress responses in higher plants. In this study, we identified and characterized OsDIRP1 (Oryza sativa Drought-Induced RING Protein 1), a nuclear-localized putative RING E3 ubiquitin (Ub) ligase in rice (Oryza sativa L.). OsDIRP1 expression was induced by drought, high salinity, and abscisic acid (ABA) treatment, but not by low temperature (4°C) stress, suggesting that OsDIRP1 is differentially regulated by different abiotic stresses. To investigate its possible role in abiotic stress responses, OsDIRP1-overexpressing transgenic rice plants (Ubi:OsDIRP1-sGFP) were generated, and their phenotypes were analyzed. The T4 Ubi:OsDIRP1-sGFP lines showed decreased tolerance to drought and salt stress as compared to wild-type rice plants. Moreover, Ubi:OsDIRP1-sGFP progeny were less sensitive to ABA than the wild-type during both germination and post-germination growth. In contrast, Ubi:OsDIRP1-sGFP plants exhibited markedly higher tolerance to prolonged cold (4°C) treatment. These results suggest that OsDIRP1 acts as a negative regulator during drought and salt stress, whereas it functions as a positive factor during the cold stress response in rice.