StSOBIR1类似基因沉默对马铃薯应答虫害的影响

Effects of silencing StSOBIR1-like gene on potato in response to herbivory

类受体激酶SOBIR1(suppressor of BIR1-1)在植物对病害的免疫应答中发挥重要作用。本研究在马铃薯中克隆了一个SOBIR1类似(StSOBIR1-like)基因,检测其在生物胁迫和非生物胁迫诱导下的表达特性;构建StSOBIR1-like基因沉默载体,并利用农杆菌介导法获得该基因的沉默株系;通过马铃薯块茎蛾生物测定实验和转录组测序,深入探究该基因沉默对马铃薯应答虫害的影响。结果表明:StSOBIR1-like基因在马铃薯叶片中高表达,马铃薯块茎蛾的模拟虫害、机械损伤以及外源施用茉莉酸甲酯、水杨酸、脱落酸等均能诱导该基因的表达,说明该基因可能参与马铃薯对生物胁迫和非生物胁迫诱导的生理反应。StSOBIR1-like沉默株系与野生型植株相比生长表型无明显差异,但马铃薯块茎蛾幼虫在前者上取食后的生物量比后者低,说明取食StSOBIR1-like沉默株系后马铃薯块茎蛾幼虫生长受到抑制。转录组测序结果表明,沉默StSOBIR1-like基因后,马铃薯植株的虫害应答在基因表达水平受到较大影响,特别是茉莉酸、水杨酸等防御激素合成通路相关基因的相对表达量总体呈上升趋势。综上所述,StSOBIR1-like基因可能负调控马铃薯对虫害的应答。本研究首次解析了StSOBIR1-like基因在马铃薯应答虫害中的功能,为进一步探究该基因调控作物抗虫的分子机制提供了依据。

Receptor-like kinase SOBIR1(suppressor of BIR1-1)plays an important role in plant immune response to diseases.In this study,a StSOBIR1-like gene from potato was cloned and its expression patterns in response to biotic stress and abiotic stress were analyzed.The gene silencing vector of StSOBIR1-like was constructed and its gene-silenced plants were generated by Agrobacterium mediated transformation.After that,a bioassay of the potato tuber moth(Phthorimaea operculella)and the transcriptome sequencing were carried out with these plants to investigate the influence of silencing StSOBIR1-like gene on the potato defense response to the potato tuber moth.The results showed that StSOBIR1-like gene was highly expressed in potato leaves.The simulated herbivory treatment of potato tuber moth,mechanical damage,and exogenous application of methyl jasmonate,salicylic acid and abscisic acid all upregulated the relative expression level of StSOBIR1-like gene,indicating that this gene might be involved in the potato defense response to both biotic stress and abiotic stress.StSOBIR1-like silenced plants and wild type plants showed similar growth phenotypes,whereas the biomass of potato tuber moth larvae was lower after feeding on the former plants,indicating that the growth of potato tuber moth was inhibited by feeding on StSOBIR1-like silenced plants.The transcriptome sequencing results showed that silencing the StSOBIR1-like gene could significantly affect the plant response to herbivory at the gene expression level,and the transcription of genes involved in defense hormone(jasmonic acid or salicylic acid)biosynthetic pathways showed an overall trend of increasing.In summary,StSOBIR1-like gene might negatively regulate potato response to herbivory.This study analyzed the function of StSOBIR1-like gene in potato response to herbivory for the first time,which provides a basis for further exploring the molecular mechanism of this gene in regulating insect resistance of crop.