Xue Rengao, Zhang Biao
Department of Life and Science, Laiyang Agricultural College, Qingdao 266109, China.
J Genet Genomics. 2007 Apr;34(4):339-46. doi: 10.1016/S1673-8527(07)60036-8.
Methyl jasmonate (MeJA) is a plant-signaling molecule that regulates plant morphogenesis and expression of plant defense genes. To determine the role of the endogenous MeJA levels in the development of plants, transgenic soybean [Glycine max (L.) Merrill] plants harboring NTR1 gene encoding for jasmonic acid carboxyl methyltransferase (JMT) were produced. The activation of NTR1 gene expression resulted in the production of MeJA. Overexpression of the NTR1 cDNA under the regulation of cauliflower mosaic virus (CaMV) 35S promoter in the transgenic soybean plants was confirmed using Northern blot analysis. The significant differences in leaf and root growth patterns were observed between the transgenic plants and the wild-type plants. The leaves of the transgenic plants were slightly elongated in length but dramatically narrowed in width compared with the nontransformed wild-type plants. In addition, elongation of primary root was inhibited in the overexpressed transgenic soybean plantlets, whereas the development of lateral root was stimulated relative to the nontransformed plants. The leaves of the transgenic plants showed 2-2.5-fold higher levels of MeJA than the control plants. These results indicated that the increased endogenous levels of MeJA is involved in regulation of morphogenesis in soybean plants.
茉莉酸甲酯（MeJA）是一种植物信号分子，可调节植物形态发生和植物防御基因的表达。为了确定内源MeJA水平在植物发育中的作用，构建了携带编码茉莉酸羧基甲基转移酶（JMT）的NTR1基因的转基因大豆[Glycine max (L.) Merrill]植株。NTR1基因表达的激活导致了MeJA的产生。通过Northern印迹分析证实了转基因大豆植株中花椰菜花叶病毒（CaMV）35S启动子调控下NTR1 cDNA的过表达。观察到转基因植株与野生型植株在叶片和根系生长模式上存在显著差异。与未转化的野生型植株相比，转基因植株的叶片长度略有伸长，但宽度显著变窄。此外，过表达的转基因大豆幼苗的主根伸长受到抑制，而侧根发育相对于未转化植株受到刺激。转基因植株叶片中的MeJA水平比对照植株高2-2.5倍。这些结果表明，内源MeJA水平的升高参与了大豆植株形态发生的调控。
