Department of Biotechnology and Kumho Life Science Laboratory, Chonnam National University, Gwangju, 500-757, Korea.
Plant Cell Rep. 2012 Sep;31(9):1677-86. doi: 10.1007/s00299-012-1280-6. Epub 2012 May 9.
An Arabidopsis β-glucosidase, AtBG1 is known to hydrolyze glucose-conjugated, biologically inactive abscisic acid (ABA) to produce active ABA, which increases the level of ABA in plants. Since an increase of ABA in plants confers tolerance against abiotic stress such as drought, we introduced the pCAMBIA3301 vector harboring the AtBG1 gene into creeping bentgrass through Agrobacterium-mediated transformation. After transformation, putative transgenic plants were selected using the BASTA resistance assay at a concentration of 0.8%. Genomic integration of the AtBG1 gene was confirmed by genomic PCR and Southern blot analysis, and gene expression was validated by Northern blot and Western blot analyses. Interestingly, the transgenic bentgrass plants overexpressing AtBG1 had a dwarf phenotype with reduced growth rates when compared to wild-type creeping bentgrass. In addition, the transgenic plants accumulated higher ABA levels and displayed enhanced drought tolerance. These results suggest that the expression of AtBG1 in plants induces the accumulation of higher ABA levels, which results in the formation of dwarf creeping bentgrass and enhances the survival in water-limiting environments.
We used an Arabidopsis β-glucosidase AtBG1 to engineer a crop with elevated active ABA levels, and developed transgenic creeping bentgrass with enhanced drought tolerance and dwarf phenotype.
拟南芥β-葡萄糖苷酶 AtBG1 已知可水解葡萄糖结合的、生物活性不活跃的脱落酸（ABA），产生活性 ABA，从而增加植物中的 ABA 水平。由于植物中 ABA 的增加赋予了对非生物胁迫（如干旱）的耐受性，我们通过农杆菌介导的转化将含有 AtBG1 基因的 pCAMBIA3301 载体引入匍匐翦股颖。转化后，使用 BASTA 抗性测定法在 0.8%的浓度下选择疑似转基因植物。通过基因组 PCR 和 Southern blot 分析证实了 AtBG1 基因的基因组整合，并通过 Northern blot 和 Western blot 分析验证了基因表达。有趣的是，与野生型匍匐翦股颖相比，过表达 AtBG1 的转基因弯叶画眉草植株表现出矮小的表型，生长速度降低。此外，转基因植物积累了更高水平的 ABA，并表现出增强的耐旱性。这些结果表明，AtBG1 在植物中的表达诱导了更高水平的 ABA 积累，从而导致矮小的匍匐翦股颖形成，并增强了在限水环境中的生存能力。
我们使用拟南芥β-葡萄糖苷酶 AtBG1 来设计具有更高活性 ABA 水平的作物，并开发了具有增强耐旱性和矮小表型的转基因匍匐翦股颖。
