Soil salinization threats the agricultural production and food security worldwide. Salt stress induced plant senescence and chloroplast degradation. However, it remains largely unknown how the chloroplast-localized proteins affect plant response to salt stress. Here, we characterized a novel gene (At5g39520) in Arabidopsis, which is induced by salt stress and encodes a chloroplast-localized protein. Thus, this gene was named SALT-INDUCED CHLOROPLAST PROTEIN (SCP). A T-DNA insertion mutant of SCP gene (scp-1) showed the enhanced tolerance to salt stress, as indicated by the increased survival rates, fresh weights and chlorophyll contents compared with wild type plants under salt treatment. Salt-induced leaf senescence was also delayed in scp-1 mutant. The scp-1 complementation line and SCP overexpression lines displayed the hypersensitivity to salt stress. The qRT-PCR analysis indicated that the transcripts of CHLOROPLAST VESICULATION (CV), which mediates stress-induced chloroplast degradation, were altered in scp-1 mutant and SCP overexpression lines. Taken together, our results suggest that SCP gene plays a negative role in response to salt stress and has potential application for genetic modification of improving plant tolerance to salt stress.

中文翻译：

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盐诱导的叶绿体蛋白（SCP）参与拟南芥对盐胁迫的植物耐受性

土壤盐渍化威胁着全世界的农业生产和粮食安全。盐胁迫诱导植物衰老和叶绿体降解。但是，很大程度上未知的叶绿体定位蛋白如何影响植物对盐胁迫的反应。在这里，我们在拟南芥中表征了一个新基因（At5g39520），该基因由盐胁迫诱导并编码叶绿体定位蛋白。因此，该基因被命名为盐诱导的叶绿体蛋白（SCP）。SCP基因的T-DNA插入突变体（scp-1）显示出对盐胁迫的增强的耐受性，这表明与盐处理的野生型植物相比，存活率，鲜重和叶绿素含量的增加。盐诱导的叶片衰老在scp-1突变体中也被延迟。的SCP-1互补线和SCP过表达株系显示的超敏反应对盐胁迫。的qRT-PCR分析表明，该转录物叶绿体囊泡形成（CV），其介导应激诱导的叶绿体降解，在被改变的SCP-1突变体和SCP过表达株系。综上所述，我们的结果表明SCP 该基因在盐胁迫响应中起着负作用，并且在提高植物对盐胁迫的耐受性的遗传修饰中具有潜在的应用。