低温下冬小麦品种间WRKY转录因子的表达特性

Expression Characteristics of WRKY Transcription Factor Between Winter Wheat Varieties in Low Temperature

WRKY转录因子可以通过调控损伤、抗病、衰老等相关基因的表达,从而参与植物的多种生理生化及生长发育过程,在植物应对逆境胁迫过程中起到至关重要的作用。为了明确低温胁迫下WRKY基因表达特性与冬小麦抗寒性的关系,进而为选择和鉴定品种抗寒性提供参考,本研究以强抗寒品种东农冬麦1号(D1)及弱抗寒品种济麦22(J22)为试验材料,经不同低温处理后,通过实时荧光定量PCR(quantitative realtime PCR,qRT-PCR)分析WRKY45、WRKY4、WRKY1、WRKY5和WRKY24五个基因的表达特性。结果表明,经低温冷冻处理后(-10℃2h及-10℃2h后再-12℃2h),D1中WRKY4、WRKY5和WRKY transcription factor 24的表达量均明显高于J22中的表达量;经低温驯化处理(10℃/4℃30d)后,D1中WRKY45表达量明显高于J22中的表达量。D1中,低温冷冻处理后WRKY1、WRKY5和WRKY transcription factor 24的表达量均显著高于低温驯化处理和常温下处理后的表达量;J22中,低温冷冻处理后WRKY45、WRKY4和WRKY transcription factor 24的表达量均显著高于低温驯化处理和常温下处理后的表达量。分析显示WRKY4、WRKY5和WRKY transcription factor 24属于冷冻应激反应型基因;其中WRKY5和WRKY transcription factor 24在不同低温处理下表达差异显著,对D1的强抗寒性起到重要调控作用。

WRKY transcription factor can regulate the expression of resistance,damage,aging-related genes,and then participated in a series of growth and development process that played an important function in response to abiotic stress.In order to reveal the relationship between expression characteristics of WRKYgene and cold resistance of winter wheat variety,and provide a reference for selection and identification of cold resistance varieties.In this experiment,cold-resistance variety Dongnongdongmai 1（D1）and cold-sensitive variety Jimai 22（J22）were used for analysis of the expression characteristics of WRKY45,WRKY4,WRKY1,WRKY5 and WRKY transcription factor 24 in response to various cold treatments by quantitative real-time PCR.The results showed that the expression of WRKY4,WRKY5 and WRKY transcription factor 24 of D1 was significantly higher than that of J22 under freezing treatment（-10℃for 2h,or-10℃for 2hand then 12℃for 2h）.The expression of WRKY45 of D1 was higher than that of J22 under cold acclimation（10℃/4℃for 30d）.In D1,the expression of WRKY1,WRKY5 and WRKY transcription factor 24 under freezing treatment was significantly higher than that under room temperature and cold acclimation.In J22,the expression of WRKY45,WRKY4 and WRKY transcription factor 24 under freezing stress was significantly higher than that under room temperature and cold acclimation.In total,the differences of the expression of WRKY5 and WRKY transcription factor 24 were larger in reponse to various treatments,compared to other WKRY genes.It is suggested that WRKY4,WRKY5 and WRKY transcription factor 24 belong to the frozen stress response genes,and WRKY5 and WRKY transcription factor 24 played an important role in cold tolerance of D1.