【目的】磷元素是植物必需的大量营养元素,在植物的生长发育中必不可少。NLA(nitrogen limitation adaptation)蛋白是一种RING型E3泛素连接酶,参与磷转运蛋白的泛素化调控,在植物体的磷素平衡调节方面发挥重要作用。以假俭草这类天然适应低磷土壤条件的植物为研究材料,通过研究假俭草EoNLA的磷高效转运分子机制,为草坪草适应酸性土壤生境的磷高效转运分子育种和栽培调控提供理论依据。【方法】通过RACE方法克隆获得EoNLA基因,应用生物信息学分析确定基因的全长序列及编码氨基酸序列,采用原生质体瞬时表达体系确定EoNLA蛋白膜定位;通过qRT-PCR方法分析EoNLA基因低磷诱导下的表达模式,并通过农杆菌介导转化拟南芥进行基因功能鉴定。【结果】EoNLA基因序列全长1 353 bp,编码一个长度为331个氨基酸的蛋白。该蛋白具有NLA蛋白典型的RING结构域和SPX结构域,EoNLA蛋白定位于细胞膜,EoNLA基因在根组织的表达量显著高于在茎和叶的表达。【结论】EoNLA基因具有根组织表达特异性,且基于拟南芥转基因植株进行的功能鉴定,进一步显示EoNLA基因具有磷素调控相关的功能。

【Obiectives】 Phosphorus is a macronutrient of plants which is essential for growth and development. Nitrogen limitation adaptation (NLA), a RING-type E3 ubiquitin ligase involved in the ubiquitin regulation of phosphorus transporters, plays an important role in the regulation of phosphorus balance in plants. 【Method】In this study, we used Eremochloa ophiuroides, which naturally adapts to low-phosphorus soil conditions, to clone the EoNLA gene using RACE. 【Result】The EoNLA gene is 1 353 bp long and encodes a protein of 331 amino acids. Amino acid sequence analysis showed that the NLA protein had a typical RING domain and an SPX domain. Cell membrane localization of the EoNLA protein was observed using a protoplast transient expression system. Agrobacterium-mediated transformation of Arabidopsis thaliana was carried out to verify gene function 【Conclusion】The qRT-PCR analysis showed that expression levels of EoNLA were significantly higher in roots than in stems and leaves, suggesting that EoNLA expression is root-specific. Furthermore, functional identification based on Arabidopsis thaliana transgenic plants suggested that EoNLA is associated with phosphorus regulation in plants.