Abstract

Potassium (K⁺) deficiency in the soil may seriously affect the yield and quality of plants, which usually satisfy their potassium requirements by engaging their K⁺ transporters and/or channels. High-affinity potassium transporter (ZmHAK) family members play crucial role in the uptake and distribution of K⁺ in maize (Zea mays L.). Here, we describe the function of ZmHAK1 promoter and its upstream regulatory transcription factors in maize. In this plant, HAK gene family includes 34 protein-encoding members, with their phylogenetic tree analysis showing both evolutionary conservativeness and diversity. ZmHAK1 gene promoter contains many functional elements related to abiotic stress. Reporter construct pCambia1301:ProZmHAK1:GUS shows that the ZmHAK1 gene is active in the roots, stems, and leaves. Using yeast one-hybrid experiment, we showed that the ZmHAK1 promoter interacts with the transcription factors ZmRAP2.11 and ZmARF2, and that these interactions occur on different fragments of the ZmHAK1 promoter. Transcription factor ZmRAP2.11 localizes in the nucleus, while ZmARF2 is found both in the nucleus and in the cell cytoplasm. In conclusion, our results suggest that the ZmHAK1 regulation has an important role in the process of absorbing potassium ions, and possibly in the response of maize to abiotic stress.

中文翻译：

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玉米中ZmHAK1启动子的功能表征及其调控转录因子

摘要

土壤中钾（K ⁺）的缺乏可能会严重影响植物的产量和质量，而植物通常通过参与其钾⁺转运蛋白和/或通道来满足钾的需求。高亲和力转运体（ZmHAK）家庭成员发挥K的吸收和扩散至关重要的作用⁺玉米（玉米L.）。在这里，我们描述了ZmHAK1启动子的功能及其在玉米中的上游调控转录因子。在该植物中，HAK基因家族包括34个蛋白质编码成员，其系统树分析显示了进化的保守性和多样性。ZmHAK1基因启动子包含许多与非生物胁迫相关的功能元件。记者构建的pCambia1301：Pro ZmHAK1：GUS显示ZmHAK1基因在根，茎和叶中有活性。使用酵母一杂交实验，我们显示ZmHAK1启动子与转录因子ZmRAP2相互作用。11和ZmARF2，并且这些相互作用发生在ZmHAK1启动子的不同片段上。转录因子ZmRAP2.11位于细胞核中，而ZmARF2位于细胞核和细胞质中。总之，我们的结果表明ZmHAK1 调节在吸收钾离子的过程中可能起重要作用，并可能在玉米对非生物胁迫的响应中起重要作用。