College of Life Science, Hebei Normal University, Shijiazhuang 050024, PR China.
College of Life Science, Hebei Normal University, Shijiazhuang 050024, PR China.
Plant Sci. 2014 Mar;217-218:63-70. doi: 10.1016/j.plantsci.2013.12.002. Epub 2013 Dec 9.
AtRPK1 (AT1G69270) is a leucine-rich repeat receptor-like protein kinase (LRR-RLK) gene in Arabidopsis thaliana. The rice gene Os07g0602700 (OsRPK1) is the homolog of AtRPK1. AtRPK1 and OsRPK1 were overexpressed and the expression of AtRPK1 was inhibited by RNAi in A. thaliana. The functional results showed that the degrees of salt tolerance of the 35S:RPK1 A. thaliana plants were significantly lower than that of the control plants. The AtRPK1-RNAi A. thaliana plants exhibited higher salt tolerance than the wild-type plants (Col). The subcellular localisation results showed that the RPK1 proteins were mainly distributed on the cell membrane and that the overexpressed AtRPK1 proteins exhibited a significantly clustered distribution. The physiological analyses revealed that the overexpression of the RPK1 genes increased the membrane permeability in the transgenic A. thaliana plants. In response to salt stress, these plants exhibited an increased Na(+) flux into the cell, which caused greater damage to the cell. The real-time quantitative PCR analysis showed that the expression of the P5CS1 gene was inhibited and the SOS signalling pathway was blocked in the 35S:AtRPK1 A. thaliana plants. These effects at least partially contribute to the salt-sensitive phenotype of the 35S:RPK1 plants.
AtRPK1（AT1G69270）是拟南芥中的一个富含亮氨酸重复受体样蛋白激酶（LRR-RLK）基因。水稻基因 Os07g0602700（OsRPK1）是 AtRPK1 的同源基因。AtRPK1 和 OsRPK1 在拟南芥中被过表达，并且 AtRPK1 的表达被 RNAi 抑制。功能结果表明，35S:RPK1 拟南芥植株的耐盐程度明显低于对照植株。AtRPK1-RNAi 拟南芥植株表现出比野生型（Col）更高的耐盐性。亚细胞定位结果表明，RPK1 蛋白主要分布在细胞膜上，而过表达的 AtRPK1 蛋白表现出明显的聚集分布。生理分析表明，RPK1 基因的过表达增加了转基因拟南芥植株的膜通透性。在盐胁迫下，这些植物表现出钠离子流入细胞的增加，从而对细胞造成更大的损伤。实时定量 PCR 分析表明，35S:AtRPK1 拟南芥植株中 P5CS1 基因的表达受到抑制，SOS 信号通路被阻断。这些影响至少部分导致了 35S:RPK1 植物的盐敏感表型。
