Mol Plant Microbe Interact. 2013 Dec;26(12):1371-7. doi: 10.1094/MPMI-04-13-0111-R.
Micro-RNAs (miRNAs) play a pivotal role in the control of gene expression and regulate plant developmental processes. miRNA 172 (miR172) is a conserved miRNA in plants reported to control the expression of genes involved in developmental phase transition, floral organ identity, and flowering time. However, the specific role of miR172 in legume nodulation is undefined. Ectopic expression of soybean miR172 resulted in an increase in nodule numbers in transgenic roots and an increase in the expression of both symbiotic leghemoglobin and nonsymbiotic hemoglobin. These nodules showed higher levels of nitrogenase activity. Further analysis revealed a complex regulatory circuit in which miR156 regulates miR172 expression and controls the level of an AP2 transcription factor. The latter, either directly or indirectly, controls the expression of nonsymbiotic hemoglobin, which is essential for regulating the levels of nodulation.
Micro-RNAs (miRNAs) 在基因表达的调控中起着关键作用，并调节植物的发育过程。miRNA 172 (miR172) 是一种在植物中保守的 miRNA，据报道它可以控制参与发育阶段转变、花器官身份和开花时间的基因的表达。然而，miR172 在豆科植物结瘤中的具体作用尚未确定。大豆 miR172 的异位表达导致转基因根中的根瘤数量增加，共生豆血红蛋白和非共生血红蛋白的表达增加。这些根瘤显示出更高水平的固氮酶活性。进一步的分析揭示了一个复杂的调控回路，其中 miR156 调控 miR172 的表达，并控制 AP2 转录因子的水平。后者直接或间接地控制非共生血红蛋白的表达，这对于调节结瘤水平至关重要。
