【摘要】 转录因子在植物对逆境胁迫的应答过程中具有重要作用,b ZIP (basic domain leucine zipper)转录因子家族是参与抗病防卫反应的一类重要转录因子。本研究依据小麦(Triticum aestivum)与叶锈菌(Puccinia triticina)互作的转录组数据库,利用热图对bZIP转录因子家族unigenes的表达进行分析,筛选得到TabZIP3基因(Genbank No. BAD97365.1),利用qRT-PCR分析该基因在小麦与叶锈菌互作过程中的表达模式。结果显示,在不亲和组合中接种后8、12和16 h该基因持续高表达,且明显高于亲和组合。Plantcare软件分析该基因包含水杨酸(salicylic acid, SA)响应元件,实验中用外源SA喷施叶表面可诱导其表达;以大麦条纹花叶病毒(Barley stripe mosaicvirus, BSMV)为载体,利用病毒诱导的基因沉默(virusinduced gene silencing, VIGS)技术沉默该基因,然后接种叶锈菌,发现在接种后48和96 h,单侵染点处过敏性反应(hypersensitive reaction, HR)面积及叶锈菌吸器母细胞(haustorial mother cell, HMC)数量明显高于对照。本研究结果表明,TabZIP3可能参与小麦抵抗叶锈菌侵染的基础防卫反应的诱发,在叶锈菌侵染诱发的HR反应中可能具有正调控作用,并且TabZIP3的表达受SA诱导。该结果为深入研究转录因子TabZIP3在小麦抵抗叶锈菌侵染中的作用机制提供了基础资料,也为利用分子育种手段培育抗叶锈小麦新品种提供了候选基因。更多还原

【Abstract】 Transcription factors play important roles in the response of plants to various stresses. The transcription factor family of bZIP(basic domain leucine zipper) is involved in the defense response against pathogen infection. In this study, the expression pattern of TabZIP3(Genbank No. BAD97365.1), a gene from the bZIP transcription factor family was obtained by screening the transcriptome database of the wheat(Triticum aestivum) infected by leaf rust fungus(Puccinia triticina). The expression patterns were visualized using heatmap, and confirmed by qRT-PCR. The expression of TabZIP3 was up-regulated after 8, 12 and 16 h post inoculation in the incompatible combination, and was obviously higher than that of the compatible combination(P<0.05). TabZIP3 was predicted to contain salicylic acid(SA) response elements, and the expression could be induced by spraying exogenous SA on the leaf surface. By using Barley stripe mosaic virus(BSMV) as a vector, the virus-induced gene silencing(VIGS) technique was used to silence TabZIP3,followed by Puccinia triticina inoculation. Hypersensitive response(HR) area and the number of haustorial mother cell(HMC) of single infection sites was much higher than that of control at 48 and 96 h(P<0.05).The research results showed that the SA inducible TabZIP3 might participated in the induction of basic defense response against Puccinia triticina infection in wheat, and might played a positive regulation role in HR response induced by Puccinia triticina. The results lay a foundational data for further study on the mechanism of the transcription factor TabZIP3 in wheat resistance to Puccinia triticina infection, and also provide an excellent candidate gene for breeding new wheat varieties resistant to Puccinia triticina.更多还原