College of Landscape Architecture and Arts, Northwest A&F University, Yangling 712100, China.
State Agricultural Biotechnology Centre, School of Veterinary and Life Sciences, Murdoch University, Perth 6150, Australia.
Int J Mol Sci. 2020 Mar 18;21(6):2083. doi: 10.3390/ijms21062083.
Eukaryotic translation elongation factors are implicated in protein synthesis across different living organisms, but their biological functions in the pathogenesis of cucumber mosaic virus (CMV) and tobacco rattle virus (TRV) infections are poorly understood. Here, we isolated and characterized a cDNA clone, encoding the alpha subunit of elongation factor 1, from a CMV-elicited suppression subtractive hybridization library of . The infection tests using CMV remarkably increased transcript abundance of ; however, it also led to inconsistent expression profiles of three other LreEF1A homologs (). Protein modelling analysis revealed that the amino acid substitutions among four LreEF1As may not affect their enzymatic functions. was ectopically overexpressed in petunia (), and transgenic plants exhibited delayed leaf and flower senescence, concomitant with increased transcription of photosynthesis-related genes and reduced expression of senescence-associated genes, respectively. A compromised resistance to CMV and TRV infections was found in transgenic petunia plants overexpressing , whereas its overexpression resulted in an enhanced tolerance to salt and drought stresses. Taken together, our data demonstrate that functions as a positive regulator in viral multiplication and plant adaption to high salinity and dehydration.
真核翻译延伸因子参与不同生物体的蛋白质合成，但它们在黄瓜花叶病毒（CMV）和烟草脆裂病毒（TRV）感染发病机制中的生物学功能还知之甚少。在这里，我们从 CMV 诱导的抑制差减杂交文库中分离和鉴定了一个 cDNA 克隆，该克隆编码伸长因子 1 的α亚基。使用 CMV 的感染测试显着增加了 的转录物丰度；然而，它也导致了其他三个 LreEF1A 同源物（）的表达谱不一致。蛋白建模分析表明，四个 LreEF1As 中的氨基酸取代可能不会影响它们的酶功能。在矮牵牛（）中异位过表达，转基因植物表现出叶片和花朵衰老延迟，分别伴随着光合作用相关基因的转录增加和衰老相关基因的表达减少。过表达 会导致转基因矮牵牛植物对 CMV 和 TRV 感染的抗性降低，而其过表达则导致对盐和干旱胁迫的耐受性增强。总之，我们的数据表明 作为病毒增殖和植物适应高盐和脱水的正向调节剂发挥作用。
