干旱胁迫下大苞萱草bHLH转录因子家族鉴定与分析

Identification and analysis of bHLH transcription factor gene family in Hemerocallis middendorffii under drought stress

【目的】为探究大苞萱草bHLH基因家族成员特性,基于对干旱胁迫下大苞萱草叶和根转录组测序结果,鉴定并分析大苞萱草bHLH基因家族成员。【方法】利用生物信息学方法对大苞萱草bHLH转录因子家族基因进行系统发育、理化性质、二级结构、保守结构域及基因表达等分析。【结果】共鉴定出55个大苞萱草bHLH家族基因并分为11个亚族;bHLH蛋白理化性质差异较大,总平均亲水性为负值,均为亲水性蛋白;亚细胞定位预测大苞萱草bHLH蛋白主要分布在细胞核中;基因表达分析表明,叶中有26个上调基因,26个下调基因,根中有32个上调基因,22个下调基因,差异基因HmbHLH50的表达量变化显著,可能与大苞萱草的抗旱能力相关。【结论】本研究为挖掘bHLH转录因子家族基因的功能奠定基础,也为深入解析大苞萱草的抗旱机制提供理论依据。

【Objective】In order to investigate the characteristics of the bHLH gene family members of Hemerocallis middendorffii, the study was conducted to identify and analyze the bHLH gene family members in H. middendorffii based on the results of transcriptome sequencing of leaves and roots of H. middendorffii under drought stress. 【Method】 The phylogeny, physicochemical properties, secondary structure, conserved domain and gene expression analysis of bHLH transcription factor family genes in H. middendorffii were analyzed through bioinformatics method. 【Result】A total of 55 bHLH family genes were identified and divided into 11 subfamilies;The physicochemical properties of bHLH protein were different and the total average hydrophilicity was negative, and all of them were hydrophilic protein;The subcellular localization prediction of bHLH protein were mainly distributed in the nucleus;Gene expression analysis showed that there were 26 up-regulated genes and 26 down-regulated genes in leaves, 32 up-regulated genes and 22 down-regulated genes in roots. The expression of differential gene HmbHLH50 changed significantly, which may be related to drought-resistance ability of H. middendorffii. 【Conclusion】All these results provide a reference for excavating functions of bHLH transcription factor family genes and for in-depth understanding of drought resistance mechanism of H. middendorffii.