【摘要】 为分析非生物胁迫下黄毛草莓FnFIT基因的表达模式，探讨FnFIT参与铁吸收的作用机制。本研究提取黄毛草莓根系总RNA，通过克隆获得基因FnFIT，并分析FnFIT的基因结构、保守基序和启动子顺式作用元件。此外，对黄毛草莓进行缺铁、铁过量、高p H值、干旱、碱、盐碱、盐七种胁迫处理，通过实时荧光定量PCR（RT-qPCR）检测FnFIT的表达模式，并测定新叶铁含量、叶绿素含量和根系铁还原酶（FCR）活性。结果表明，FnFIT编码区全长984 bp，编码327个氨基酸，属于bHLH家族。FnFIT启动子区具有脱落酸、茉莉酸等激素调控元件、光响应元件、干旱、低温等逆境诱导元件，以及DNA结合蛋白结合位点、G-box元件。RT-qPCR结果显示FnFIT主要在根系中表达，且在缺铁、高pH值、干旱、碱、盐碱、盐等胁迫下基因表达量提高，铁过量诱导FnFIT表达量下降。FCR活性变化与FnFIT表达模式基本一致。缺铁和高pH值处理导致新叶叶绿素含量和Fe²⁺含量显著降低。盐碱和盐胁迫会导致叶片叶缘焦枯，而缺铁处理表现出黄化症状。铁过量处理对草莓产生毒害症状，导致草莓根系发黑，叶绿素含量和Fe²⁺含量显著下降。研究结果可为草莓铁吸收调控机制和培育抗盐碱的草莓品种提供依据。更多还原

【Abstract】 To analyze the expression pattern of FnFIT gene in abiotic stress and explore the mechanism of FnFIT in iron absorption. In this study, total RNA was extracted from the root system of Fragaria nilgerrensis, and FnFIT gene was cloned. The gene structure, conserved motif and promoter cis-acting elements of FnFIT were analyzed.At the same time, the researchers treated strawberry seedlings with iron deficiency, iron excess, high pH, drought,alkali, saline-alkali and salt, and then studied the expression pattern of FnFIT by real-time fluorescent quantitative PCR（RT-qPCR）, and iron content and chlorophyll content in new leaves and iron reductase（FCR） activity in roots were determined. The results showed that the full-length coding sequence of FnFIT was 984 bp, encoding a 327-amino-acid protein. Its promoter contained ABA, JA and other hormone regulatory elements, light response elements, drought and low temperature stress inducing elements, DNA binding protein binding sites and G-box. The results of RT-qPCR showed that FnFIT was mainly expressed in roots, and the expression of FnFIT increased under iron deficiency, high pH, drought, alkali, saline-alkali and salt stress, and decreased due to iron excess. The change of FCR activity was basically consistent with the expression pattern of FnFIT. Iron deficiency and high pH treatment led to a significant decrease of chlorophyll content and Fe²⁺ content in young leaves. Saline-alkali and salt stress would lead to leaf edge scorching, but only iron deficiency treatment showed chlorosis symptoms.Drought, alkali, saline-alkali and salt stress would not lead to a decrease in chlorophyll content and Fe²⁺ content.Excessive iron treatment produced toxic symptoms on Fragaria nilgerrensis, resulting in the blackening of Fragaria nilgerrensis roots and the significant decrease of chlorophyll content and Fe²⁺ content. The results could provide a basis for the regulation mechanism of iron absorption and the cultivation of saline-resistant strawberry varieties.更多还原