Chen Yahui, Peng Xuefeng, Cui Jijie, Zhang Hongxia, Jiang Jiang, Song Zhizhong
Collaborative Innovation Center of Sustainable Forestry in Southern China of Jiangsu Province, Nanjing Forestry University, Nanjing, Jiangsu, China.
The Engineering Research Institute of Agriculture and Forestry, Ludong University, Yantai, Shandong, China.
Int J Genomics. 2021 Feb 25;2021:6669509. doi: 10.1155/2021/6669509. eCollection 2021.
Potassium (K) plays key roles in plant growth and development. However, molecular mechanism studies of K nutrition in forest plants are largely rare. In plants, gene encodes for the outward rectifying Shaker-type K channel that is responsible for the long-distance transportation of K through xylem in roots. In this study, we determined a Shaker-type K channel gene in purple osier (), designated as , and determined its function using a patch clamp electrophysiological system. SpuSKOR was closely clustered with poplar PtrSKOR in the phylogenetic tree. Quantitative real-time PCR (qRT-PCR) analyses demonstrated that was predominantly expressed in roots, and expression decreased under K depletion conditions. Patch clamp analysis via HEK293-T cells demonstrated that the activity of the SpuSKOR channel was activated when the cell membrane voltage reached at -10 mV, and the channel activity was enhanced along with the increase of membrane voltage. Outward currents were recorded and induced in response to the decrease of external K concentration. Our results indicate that SpuSKOR is a typical voltage dependent outwardly rectifying K channel in purple osier. This study provides theoretical basis for revealing the mechanism of K transport and distribution in woody plants.
钾（K）在植物生长发育中起着关键作用。然而，森林植物钾营养的分子机制研究在很大程度上较为罕见。在植物中，基因编码外向整流型Shaker家族钾通道，该通道负责钾在根部通过木质部的长距离运输。在本研究中，我们在紫柳（）中鉴定出一个Shaker家族钾通道基因，命名为，并用膜片钳电生理系统确定了其功能。在系统发育树中，SpuSKOR与杨树PtrSKOR紧密聚类。定量实时PCR（qRT-PCR）分析表明，主要在根中表达，在钾缺乏条件下表达降低。通过HEK293-T细胞进行的膜片钳分析表明，当细胞膜电压达到-10 mV时，SpuSKOR通道的活性被激活，并且通道活性随着膜电压的增加而增强。记录到外向电流并响应外部钾浓度的降低而诱导产生。我们的结果表明，SpuSKOR是紫柳中一个典型的电压依赖性外向整流钾通道。本研究为揭示木本植物中钾运输和分配机制提供了理论依据。
