- Human leukocyte antigen-B associated transcript 1 (BAT1) also called as UAP56 is a DExD/H-box protein involved in messenger RNA (mRNA) splicing. The activities of ascorbate peroxidase, guaiacol peroxidase, malondialdehyde and glutathione reductase were significantly higher in transgenics indicating the presence of an efficient antioxidant defence system which helps to cope with salinity-induced oxidative damages.
- Microarray analysis of OsBAT1 overexpressing transgenic lines revealed up-regulation of stress-responsive genes of different pathways including the spliceosome. Transcription factor genes like MYB, NAC and WRKY, DREB and MADS-box protein that are known to improve stress adaptation were found to be up-regulated in OsBAT1 overexpressing lines.
- Transgenic lines
- Quantitative real-time PCR (qRT-PCR) showed ∼10-fold induction in the transcript level of sense transgenic lines as compared to control plants grown under normal condition. GUS activity was shown in leaf tissues of all the transgenic lines, while no blue colour was observed in control plants.
- ROS scavenging capacity in transgenic lines, the photosynthetic machinery is affected by the salinity stress in both transgenics and control plants, but control plants showed more damage as compared to T1 transgenic plants.
- Rice overexpressing OsBAT1 (T1 and T2 generations) show tolerance to high salinity (200 mM NaCl) stress. The T1 transgenics exhibited higher levels of biochemical parameters such as water and chlorophyll contents, net photosynthetic rate, stomatal conductance and intercellular CO2 content as compared to null-segregant (control) plants. Agronomic parameters were also higher in transgenics as compared to control. OsBAT1 and OsAAP6 are highly expressed in roots and seeds, respectively.
- It is evident that transgenic plants have more tolerance to salinity stress. Higher chlorophyll content in the leaf discs from all the above transgenic plants provides a positive relationship between theT1 transgenic lines and tolerance to salinity stress in both mild (100 mM) and severe (200 mM) NaCl concentrations.
- The T1 OsBAT1 overexpressing plants accumulated 2-fold more glucose and 2.5-fold more fructose in both roots and shoots as compared to the control plants during salt stress. The leaf disc assay plants survived efficiently up to maturity and formed viable seeds, whereas control plants died completely.
For cellular localization, gold particles coated with the plasmid construct OsBAT1-GFP or 35S-GFP (control) were bombarded into onion epidermal cells and examined by confocal microscopy after 48 h of incubation. The results showed that OsBAT1 is localized in nucleus and plasma membrane.
- A total of 85 AAT genes were identified in rice genome and were classified into eleven distinct subfamilies based upon their sequence composition and phylogenetic relationship. A large number of OsAAT genes were expanded via gene duplication, 23 and 24 OsAAT genes were tandemly and segmentally duplicated, respectively.
- OsBAT1 belongs to ACT subfamily.
- Plant AATs family includes two main families that belong to the amino acid-polyamine- choline (APC) transporter superfamily: the amino acid/auxin permease (AAAP) family and the APC family. There are at least six subfamilies in the AAAP family, including amino acid permeases (AAPs), lysine and histidine transporters (LHTs), proline transporters (ProTs), c-aminobutyric acid transporters (GATs), auxin transporters (AUXs), and aromatic and neutral amino acid transporters (ANTs). The APC family in plants is grouped into three subfamilies: cationic amino acid transporters (CATs), amino acid/choline transporters (ACTs) and polyamine H+-symporters (PHSs).
- Amino acid transporters (AATs) are the integral membrane proteins which mediate the transport of amino acids across cellular membranes in higher plants, and play an indispensable role in various processes of plant growth and development, including long distance amino acid transport, response to pathogen and abiotic stresses.
Labs working on this gene
- International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China
- Tuteja N, Sahoo R K, Huda K M K, et al. OsBAT1 Augments Salinity Stress Tolerance by Enhancing Detoxification of ROS and Expression of Stress-Responsive Genes in Transgenic Rice[J]. Plant Molecular Biology Reporter, 2014: 1-18.
- Zhao H, Ma H, Yu L, et al. Genome-wide survey and expression analysis of amino acid transporter gene family in rice (Oryza sativa L.)[J]. PloS one, 2012, 7(11): e49210.
- Saier M H, Yen M R, Noto K, et al. The transporter classification database: recent advances[J]. Nucleic acids research, 2009, 37(suppl 1): D274-D278.
- Ortiz-Lopez A, Chang H C, Bush D R. Amino acid transporters in plants[J]. Biochimica et Biophysica Acta (BBA)-Biomembranes, 2000, 1465(1): 275-280.
- Okumoto S, Pilot G. Amino acid export in plants: a missing link in nitrogen cycling[J]. Molecular plant, 2011, 4(3): 453-463.
- Tegeder M, Offler C E, Frommer W B, et al. Amino acid transporters are localized to transfer cells of developing pea seeds[J]. Plant Physiology, 2000, 122(2): 319-326.
- Wipf D, Ludewig U, Tegeder M, et al. Conservation of amino acid transporters in fungi, plants and animals[J]. Trends in biochemical sciences, 2002, 27(3): 139-147.