独行菜抗冷相关基因的克隆及表达分析

【目的】独行菜在种子萌发和幼苗生长阶段可耐受一定程度的低温胁迫,研究独行菜的低温耐受机制。【方法】设计兼并引物,从独行菜冷诱导叶片的cDNA中克隆获得LaCBF3和LaCOR15a基因核心片段。利用半定量RT-PCR法分析两个基因在不同胁迫处理下的表达情况。【结果】获得442 bp LaCBF3及405 bp LaCOR15a核心片段,经比对与拟南芥CBF3、COR15a基因核心片段相似性分别为84.38%、81.8%。半定量RT-PCR结果显示在独行菜幼苗中,LaCOR15a基因不仅响应低温胁迫,还能迅速响应高盐、干旱及ABA处理,不同条件下表达各有差异。LaCBF3仅对低温胁迫响应迅速。【结论】LaCBF3、LaCOR15a在独行菜幼苗响应低温胁迫的分子机制中具有重要的调控作用,且LaCOR15a基因也应答干旱、高盐等非生物胁迫。

Cloning and Expression Analysis of Cold Resistance Genes in Lepidium apetalum

【Objective】 Our previous studies of Lepidium apetalum Willd. showed that it could tolerate a certain degree of low temperature stress during germination and seedling growth. To further explore the mechanisms of cold tolerance in Lepidium apetalum, we cloned two key genes of cold resistance signal pathway named LaCBF3 and LaCOR15a and analyzed their expression patterns responded to abiotic stress.【Method】LaCBF3 and LaCOR15a genes were cloned by PCR method from cDNA of cold induced leaves of Lepidium plants using degenerate primers.【Result】The conservative regions of cloned 442 bp LaCBF3 and 405 bp LaCOR15a gene fragments had 84.38% and 81.8% similarity to Arabidopsis thaliana CBF3 gene and COR15a gene respectively. Semi quantitative RT-PCR showed that the LaCOR15a gene responded to low temperature stress as well as drought, salt and ABA treatment, while LaCBF3 only responded to low temperature stress rapidly in Lepidium seedlings. 【Conclusion】LaCBF3 and LaCOR15a play important regulatory roles in responding to low temperature in Lepidium apetalum during germination and seedling growth. Besides, LaCOR15a gene also responds to other abiotic stress such as drought, salt as well as ABA treatment.