The control of promoter activity by nitrogen source has recently emerged as an intriguing system for regulated expression of the heterologous genes. The purpose of this work was to investigate whether heterologous gene expression in transgenic Dunaliella salina would be controlled by an inducible promoter. Here we identify that the nitrate reductase (NR) transcripts of D. salina are induced by nitrate but repressed by ammonium. The bar gene integrated into the genome of D. salina is transcribed by a promoter of the NR gene from D. salina and the bar transcripts are induced by nitrate but repressed by ammonium. PPT-resistance of transformants disappears when they are transferred from nitrate-containing medium to ammonium-containing medium. The findings of this study demonstrate that the promoter of the D. salina NR gene can be used to control expression of the heterologous genes in transgenic D. salina.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.gene.2007.08.001 | DOI Listing |
Plant Sci
December 2024
Instituto de Fisiología Vegetal (INFIVE CCT CONICET La Plata), Universidad Nacional de La Plata (UNLP) y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). Diagonal 113 Nº 495 (1900) La Plata, Argentina. Electronic address:
Nitrate reductase (NR) is an essential enzyme because of its role in nitrogen metabolism and in key signaling events through the generation of the reactive nitrogen species, nitric oxide (NO). In this work, we evaluated changes in endogenous NO levels during the onset of P-restriction in soybean plants (Glycine max), focusing on the possible pathways involved in its generation, namely NR and NO synthase like activity, NOS, and the subsequent role of NR during low P-acclimation. During the first 96h of P-starvation NO levels increased in the leaves.
View Article and Find Full Text PDFBioresour Technol
December 2024
Department of Ecology, College of Life Science and Technology, Jinan University, Guangzhou 510632, Guangdong, China. Electronic address:
This study cultivated a bacterial consortium (S60) from landfill leachate that exhibited effective heterotrophic nitrification and aerobic denitrification (HN-AD) properties. Under aerobic conditions, the removal of NH-N reached 100 % when the S60 consortium utilised NH-N either as the sole nitrogen source or in combination with NO-N and NO-N. Optimal HN-AD performance was achieved with sodium acetate as a carbon source and a pH of 7.
View Article and Find Full Text PDFPlant Physiol Biochem
December 2024
Department of Pomology, Faculty of Agriculture, Assiut University, Assiut, 71526, Egypt; Biology Research & Studies Institute, Assiut University, Assiut, 71526, Egypt. Electronic address:
Smart nanohybrid technology with potential advantages to plants has recently been developed formanaging the widespread pollution of heavy metals. Herein, we disclose a novel strategy to combat Pb stress in strawberry (Fragaria spp. cv.
View Article and Find Full Text PDFWater Res
December 2024
School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510006, China. Electronic address:
Marine anammox bacteria-based Fe(II)-driven autotrophic denitratation and anammox (MFeADA) was investigated for nitrogen removal from saline wastewater for the first time. The study demonstrated that varying influent doses of Fe(II), which participate in the Fe cycle, significantly influenced nitrogen removal performance by altering the fate of nitrite. When 50 mg/L Fe(II) was added, the nitrogen removal was mainly performed by the anammox and Fe(II)-driven autotrophic denitratation (FeAD).
View Article and Find Full Text PDFBMC Plant Biol
December 2024
The Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 21, Kraków, 30-239, Poland.
The aim of this work was to check the effects of five Bradyrhizobium japonicum inoculants from different producers on growth, photochemical efficiency, nitrate reductase activity, amount of hydrogen peroxide, activity of catalase, non-specific peroxidase, and superoxide dismutase, seed yield, and nodulation of soybean cv. 'Malaga'. We also evaluated expression of such nodulation genes as NIC1, NOD21, and NORKb.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!