植物硼营养高效的分子调控途径

Molecular regulatory pathways for boron efficiency in plants

植物体内的硼主要存在于细胞壁中,对稳定细胞壁结构和促进生长发育起重要作用。双子叶植物需硼多,对缺硼敏感,但不同物种及不同品种对缺硼的抗性存在极显著的基因型差异。华中农业大学王运华教授在1990年代带领团队开展甘蓝型油菜硼高效品种的筛选,从此开启了我国植物硼营养高效利用的遗传与分子机制研究。近10多年的研究结果表明,植物响应缺硼胁迫提高硼效率存在2条不同的分子调控途径。(1)依赖硼转运基因的途径。在这条途径中,NIPs和BORs家族基因受缺硼诱导表达增强根系对土壤硼的吸收和体内硼的转运分配,实现硼的高效吸收和转运,进而提高植物对缺硼胁迫的抗性或适应性;(2)独立于硼转运基因的途径。该途径中,植物通过影响激素信号和细胞壁合成代谢相关基因的表达,调节根系生长发育和细胞壁组分结构等方式,提高体内硼的利用效率,进而增强植物对缺硼的抗性。在硼被确定为植物必需营养元素的百年纪念之际,我们对这一工作进行综述归纳,以飨读者。同时,在王运华先生逝世1周年之际,深切缅怀先生在开启华中农业大学作物硼营养遗传研究领域中所做的奠基性贡献。

Boron in plants is mainly present in cell walls and plays an important role in stabilizing the structure of cell wall and promoting the growth and development of plants.Eudicots require more boron and are sensitive to boron deficiency,but there are significant genotypic differences in the resistance of different species and varieties to boron deficiency.Professor Yunhua Wang from Huazhong Agricultural University led a team to screen boron efficient varieties of Brassica napus in the early 1990s,thus initiating studies on the genetic and molecular mechanisms of boron efficiency in plants in China.The results of studying over a decade showed that there were two different molecular regulatory pathways for plants to improve boron efficiency under boron deficiency.In the B transporter-dependent pathway,the expression of NIPs and BORs family genes is induced by boron deficiency,which enhances the absorption of B in root and the distribution of B in shoot,achieving efficient absorption and transport of boron,thereby improving the resistance and adaptability of plants under B deficiency.In the B transporter-independent pathway,plants improve the utilization efficiency of boron in their shoot by influencing hormone signals and the expression of genes related to cell wall synthesis and metabolism,regulating the growth and development of root,and the structure of cell wall component,thereby enhancing plant resistance to boron deficiency.On the 100th anniversary of boron being identified as an essential nutrient for plants,the author reviewed and summarized these researches to enrich readers.At the same time,on the first anniversary of Mr.Wang Yunhua’s pass away,it is to commemorate his groundbreaking contribution in initiating the field of genetic studies on crop boron nutrition at Huazhong Agricultural University.