小麦中带有核定位信号NAC转录因子的鉴定及分析

Genome-wide identification of NAC transcription factors with nuclear localization signal in wheat

NAC(NAM/ATAF/CUC)是植物特有的一类转录因子,在生物和非生物胁迫中发挥着重要作用。本研究从小麦基因组中鉴定出9个C末端带有核定位信号的NAC转录因子,对其理化性质、系统发育模式、保守基序进行了分析。结果表明,这9个NAC转录因子均是亲水蛋白,分子量范围在19.63~28.92 kD之间,等电点范围在8.40~9.87之间,同一亚族成员具有相似的保守基序。对这9个NAC转录因子在小麦与条锈菌、赤霉菌互作过程中的表达变化进行了模拟分析,发现TaNACL-B1和TaNACL-D1的表达受条锈菌和赤霉菌的诱导。利用实时荧光定量PCR(Quantitative real-time PCR,qPCR)技术检测了接种叶锈菌的小麦中TaNACL-A1、TaNACL-B1和TaNACL-D1的表达模式,结果显示,3个基因的表达量在小麦与叶锈菌亲和互作与非亲和互作中存在明显差异,均在12~72 h呈上升趋势,在亲和组中的表达量高于非亲和组,表明它们可能在小麦与叶锈菌互作过程中发挥负调控作用。综上所述,本研究初步筛选到了与小麦抗病相关的带有核定位信号的NAC转录因子,为研究NAC转录因子在小麦与病原物互作过程中的作用提供了参考。

NAC(NAM/ATAF/CUC,NAC)is a kind of transcription factors unique to plants and plays an important role in biotic and abiotic stresses.In this study,nine NAC transcription factors with nuclear localization signal at C-terminal were identified from wheat genome,and their physicochemical properties,phylogentic model and conserved motifs were analyzed.The results showed that nine NAC transcription factors were hydrophilic proteins with molecular weight ranging from 19.63~28.92 kD,and isoelectric point ranging from 8.40 to 9.87.The same groups contain similar conserved motifs.Stimulation analysis showed that the expression of TaNACL-B1 and TaNACL-D1 was induced by Puccinia striiformis f.sp.tritici and Fusarium graminearum.The expression patterns of three genes,TaNACL-A1,TaNACL-B1,TaNACL-D1 in wheat inoculated with Puccinia triticina(Pt)were detected by quantitative real-time PCR(qPCR).The expression of TaNACL genes showed significant difference between compatible and incompatible interaction of wheat and Pt,and upregulated expression from 12 to 72 h.The expression level of TaNACL genes in the incompatible interaction is higher than that in the compatible interaction,indicating that they might play a negative role in the interaction of wheat and Pt.Taken together,NAC transcription factors with nuclear localization signals related to wheat disease resistance were screened,which provided a reference for studying the role of NAC transcription factors in the interaction between wheat and pathogens.