Maize is acutely vulnerable to water deficit. Due to the slow progress in conventional breeding, more beneficial genes should be transformed into maize for improvement of drought tolerance. In the present study, the vacuolar H⁺-pyrophosphatase (H⁺-PPase) gene (AnVP1) from Ammopiptanthus nanus was transformed into maize by Agrobacterium-mediated calli transformation. After identification of integration and ectopic expression of the AnVP1 gene by PCR amplification, DNA resequencing, reverse transcription PCR, real-time quantitative PCR, Western blotting and measurement of H⁺-PPase content, the transgenic lines were evaluated for their drought tolerance in greenhouse and field. The results of greenhouse phenotyping showed that the expression of AnVP1 decreased the negative effects of drought stress on transgenic maize with the improved performance, higher germination ratio, relative water content, biomass and more robust root system, slightly blasted leaves, lower electrolyte leakage and malondialdehyde content. The results of yield phenotyping showed that kernel yield of L1, L4 and L10 lines was significantly higher than WT under water deficit conditions. In conclusion, ectopic expression of the AnVP1 gene significantly enhanced drought tolerance of the transgenic maize, which is hopefully used for commercialized release after further safety assessment, because the expression of some endogenous genes was affected slightly.

中文翻译：

---

沙冬青液泡 H+-焦磷酸酶 (H+-PPase) 基因的过表达增强了玉米的耐旱性

玉米极易受到缺水的影响。由于常规育种进展缓慢，应将更多有益基因转化到玉米中以提高耐旱性。在本研究中，通过农杆菌介导的愈伤组织转化将沙冬青的液泡H ⁺ -焦磷酸酶（H ⁺ -PPase）基因（AnVP1）转化到玉米中。通过 PCR 扩增、DNA 重测序、逆转录 PCR、实时定量 PCR、蛋白质印迹和 H ^{+测量鉴定}AnVP1基因的整合和异位表达后 -PPase含量，转基因品系在温室和大田中的耐旱性进行了评估。温室表型分析结果表明，AnVP1的表达降低了干旱胁迫对转基因玉米的负面影响，其性能得到改善，发芽率、相对含水量、生物量和更健壮的根系，叶片轻微爆裂，电解质泄漏和丙二醛降低。内容。产量表型结果表明，在缺水条件下，L1、L4和L10品系的籽粒产量显着高于WT。总之，AnVP1的异位表达该基因显着增强了转基因玉米的耐旱性，由于部分内源基因的表达受到轻微影响，因此有望在进一步安全评估后用于商业化释放。