为研究香蕉MAPK1的序列特征及其在不同激素处理、逆境胁迫下的表达趋势,以‘天宝蕉’为材料,采用RT-PCR技术克隆MaMPK1并对其进行生物信息学分析和不同处理下的表达模式分析.结果显示该基因编码区长为1 182 bp,可编码393个氨基酸.其编码蛋白具有STKc_TEY_MAPK结构域,属于MAPK基因家族TEY亚型A亚家族,是不稳定的脂溶性亲水酸性蛋白,无信号肽和跨膜结构,有多个磷酸化位点.亚细胞定位预测结果显示MaMPK1主要定位于细胞核.蛋白互作预测结果显示该蛋白与HSFA4A存在互作,暗示其可能在香蕉抗热反应过程中发挥作用.启动子顺式作用元件预测结果显示MaMPK1启动子包含多种激素和逆境胁迫相关作用元件.定量分析结果显示MaMPK1的表达受SA、45 ℃、低温和盐胁迫抑制,受茉莉酸甲酯(MeJA)和枯萎病菌侵染诱导上调,在脱落酸(ABA)处理后期极显著上调表达.本研究表明MaMPK1广泛参与香蕉逆境胁迫应答.
To reveal the sequence characteristics of the banana MAPK1 gene and its expression pattern under different phytohormone and stress treatments, MaMPK1 was cloned from ‘Tianbaojiao’ banana using RT-PCR and was subjected to a series of bioinformatic and expression pattern analysis. The coding sequence of MaMPK1 was 1 182 bp in length and was predicted to encode 393 amino acids. The MaMPK1-encoded protein contained a STKc_TEY_MAPK domain and belonged to the TEY subtype and a subfamily of the MAPK gene family. It was an unstable liposoluble hydrophilic acidic protein without a signal peptide or transmembrane structure and with multiple phosphorylation sites. Subcellular localization prediction results showed that MaMPK1 are mainly located in the nucleus. Protein interaction prediction results indicated that the protein may interact with HSFA4A, signifying that it functions in the banana heat response. An analysis to predict promoter cis-acting elements identified multiple phytohormones and stress-related cis elements. The results of quantitative real time PCR analysis showed that the expression of MaMPK1 was inhibited by SA, 45 °C high temperature, low temperature, and salt stress treatments;upregulated by methyl jasmonate (MeJA) and banana fusarium wilt pathogen infection;and significantly upregulated at the late stage of abscisic acid (ABA) treatment. This study showed that MaMPK1 are widely involved in banana stress responses.
Chinese Journal of Applied and Environmental Biology