SlHVA22l基因调节番茄耐旱性

Investigation of the Regulation of Drought Tolerance by the SIHVA22I Gene in Tomato

植物在生长发育过程中面临各种非生物胁迫。其中干旱胁迫严重影响作物生长,降低其产量。植物中以TB2/DP1结构域为特征的HVA22蛋白参与调控生长发育和非生物胁迫响应。然而,HVA22在番茄(Solanum lycopersicum)干旱胁迫响应中的功能尚不清楚。该研究探索了番茄SlHVA22l基因的功能。结果表明,番茄SlHVA22l与其它双子叶植物中的HVA22l同源蛋白具有较高的序列相似性。表达模式分析显示,SlHVA22l基因表达受干旱胁迫和植物激素(ABA和Me JA)诱导。此外,通过酵母(Saccharomyces cerevisiae)异源表达和病毒诱导基因沉默技术沉默番茄SlHVA22l基因,验证了SlHVA22l基因的抗旱功能。干旱处理后沉默植株表现出较高的过氧化氢(H_(2)O_(2))和丙二醛(MDA)含量,以及较低的O_(2)^(·-)清除率,且其超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)的活性较对照显著降低。综上表明,SlHVA22l基因在番茄抵御干旱胁迫中发挥重要作用。

Plants inevitably face a multitude of abiotic stresses during their growth and development stages.Drought stress significantly hampers crop growth and reduces yield.The plant HVA22 protein is characterized by the TB2/DP1 structural domain and is implicated in the modulation of plant growth,development,and responses to abiotic stress.However,its precise function in the context of drought stress response in tomato remains to be elucidated.Therefore,in this study,we investigated the functional role of the tomato SIHVA22I gene in drought tolerance.The results showed that the amino acid sequence of SIHVA22I exhibits a higher degree of sequence similarity to that of homologous HVA22I proteins found in other dicotyledonous plants.Furthermore,the expression pattern analysis revealed a significant upre-gulation of the SIHVA22I gene in response to drought stress and phytohormones(ABA and MeJA).Moreover,the function of the SIHVA22I gene in drought tolerance was subsequently verified by yeast heterologous expression and silencing of the endogenous SIHVA22I gene in tomato via virus-induced gene silencing.The silenced plants exhibited higher H_(2)O_(2) and malondialdehyde contents,as well as lower O_(2)^(·–).scavenging after drought treatment.Moreover,the activities of su-peroxide dismutase,peroxidase,catalase,and ascorbate peroxidase were significantly decreased in the silenced plants compared to those in the control plants.Collectively,these results indicate that the SIHVA22I gene plays an important role in tomato resistance to drought stress.