Baldoni A, Von Pinho E V R, Fernandes J S, Abreu V M, Carvalho M L M
Laboratório Central de Sementes, Departamento de Agricultura, Universidade Federal de Lavras, Lavras, MG, Brasil.
Genet Mol Res. 2013 Feb 28;12(3):2618-24. doi: 10.4238/2013.February.28.2.
The study of gene expression in plants is fundamental, and understanding the molecular mechanisms involved in important biological processes, such as biochemical pathways or signaling that are used or manipulated in improvement programs, are key for the production of high-quality soybean seeds. Reports related to gene expression of lignin in seeds are scarce in the literature. We studied the expression of the phenylalanine ammonia-lyase (PAL), cinnamate 4-hydroxylase, 4-hydroxycinnamate 3-hydroxylase, and cinnamyl alcohol dehydrogenase genes involved in lignin biosynthesis during the development of soybean (Glycine max L. Merrill) seeds. As the endogenous control, the eukaryotic elongation factor 1-beta gene was used in two biological replicates performed in triplicate. Relative quantitative expression of these genes during the R4, R5, R6, and R7 development stages was analyzed. Real-time polymerase chain reaction was used for the gene expression study. The analyses were carried out in an ABI PRISM 7500 thermocycler using the comparative Ct method and SYBR Green to detect amplification. The seed samples at the R4 stage were chosen as calibrators. Increased expression of the cinnamate-4-hydroxylase and PAL genes occurred in soybean seeds at the R5 and R6 development stages. The cinnamyl alcohol dehydrogenase gene was expressed during the final development phases of soybean seeds. In low-lignin soybean cultivars, the higher expression of the PAL gene occurs at development stages R6 and R7. Activation of the genes involved in the lignin biosynthesis pathway occurs at the beginning of soybean seed development.
植物基因表达的研究至关重要，了解重要生物学过程中涉及的分子机制，如在改良计划中使用或操纵的生化途径或信号传导，是生产高质量大豆种子的关键。文献中关于种子中木质素基因表达的报道很少。我们研究了大豆（Glycine max L. Merrill）种子发育过程中参与木质素生物合成的苯丙氨酸解氨酶（PAL）、肉桂酸4-羟化酶、4-羟基肉桂酸3-羟化酶和肉桂醇脱氢酶基因的表达。作为内参，真核延伸因子1-β基因在两个生物学重复中进行了三次重复实验。分析了这些基因在R4、R5、R6和R7发育阶段的相对定量表达。采用实时聚合酶链反应进行基因表达研究。分析在ABI PRISM 7500热循环仪中使用比较Ct法和SYBR Green检测扩增。选择R4阶段的种子样品作为校准物。肉桂酸4-羟化酶和PAL基因在大豆种子的R5和R6发育阶段表达增加。肉桂醇脱氢酶基因在大豆种子发育的最后阶段表达。在低木质素大豆品种中，PAL基因在R6和R7发育阶段表达较高。木质素生物合成途径中相关基因的激活发生在大豆种子发育初期。
