蒙古冰草MwMYB4基因功能鉴定

Functional Identification of MwMYB4 Gene from Agropyron mongolicum Keng

MwMYB4基因是从蒙古冰草中克隆得到的MYB类转录因子家族成员之一。该研究以转MwMYB4基因的拟南芥后代为材料,通过在干旱和低温胁迫下对转基因植株进行表型分析、理化指标测试和分子鉴定,分析并验证MwMYB4基因的功能。结果显示:(1)蒙古冰草MwMYB4基因已成功整合到转基因拟南芥T1代的基因组中并实现转录水平的表达。(2)转基因拟南芥T2代植株在干旱胁迫条件下,转基因植株叶片枯黄程度较轻,相对电导率较野生型变化幅度低,脯氨酸含量明显高于野生型对照,且MwMYB4基因的表达量随干旱胁迫时间延长而增加。(3)在低温胁迫条件下,转基因拟南芥叶片的枯白程度明显低于野生型,且MwMYB4基因的表达量随低温胁迫时间增加而增加。研究表明,过量表达蒙古冰草MwMYB4基因能够提高转基因拟南芥对干旱和低温的耐受性,该基因可能在干旱胁迫和低温胁迫调控机制中发挥调控作用,可作为改良农作物和其他牧草抗旱、抗寒性的重要候选基因。

MwMYB4 gene is a member of the MYB transcription factor family cloned from Agropyron mongolicum Keng.The progeny of transgenic Arabidopsis with MwMYB4 gene were used as materials in this study.The phenotype analysis and molecular identification of transgenic plants under drought and low temperature stress were used to analyze and verify the function of MwMYB4 gene.The results showed that:(1)the MwMYB4 gene has been successfully integrated into the genome of transgenic T1 A.thaliana and achieved transcription-level expression.(2)Under drought stress,the transgenic A.thaliana plants showed less yellowing,and the relative conductivity was lower than that of the wild type,but the change was not significant.The content of proline was significantly higher than that of the wild type control.The expression level increased with the duration of drought stress.(3)Under low temperature stress,the paleness of transgenic Arabidopsis leaves was significantly lower than that of wild type,and the expression level of MwMYB4 gene increased with the increase of low temperature stress time.Studies have shown that overexpression of MwMYB4 gene from Agropyron mongolicum can increase the tolerance of transgenic Arabidopsis to drought and low temperature.This gene may play a regulatory role in the regulation mechanism of drought stress and low temperature stress,and can be an important candidate gene for improving drought and cold resistance of crops and other forages.