干旱胁迫下丹参数字基因表达谱分析

Analysis of Digital Gene Expression in Salvia miltiorrhiza under Drought-Stress

丹参是中国传统大宗药材,具有重要的药用价值,但其品质受干旱胁迫影响较大,而对丹参响应干旱胁迫的应答机制尚不明确。本研究基于数字基因表达谱技术,对干旱胁迫处理后的丹参植株cDNA文库进行了差异基因表达谱分析。分析结果表明,共有5 740条基因受干旱胁迫诱导差异表达,其中1 143条表达上调,4 597条表达下调。Gene Ontology （GO）功能显著性富集分析表明,干旱胁迫应答基因的生物学功能主要集中在催化活性和结合活性中。Pathway显著性富集分析结果表明,上调基因显著富集在黄酮生物合成途径、核糖体途径、苯基丙酸类生物合成途径、半胱氨酸蛋氨酸代谢途径和植物激素生物合成等途径,下调基因则主要富集在鞘糖脂的合成途径、糖胺聚糖降解途径、卟啉代谢和叶绿素代谢途径上。随机抽取9个差异表达基因进行实时荧光定量PCR验证,其结果与EDG检测结果一致。本研究的分析结果有助于进一步了解丹参响应干旱胁迫的分子机制,为干旱应答功能基因的筛选奠定基础。

Salvia mihiorrhiza is a well-known traditional herbal. However, its quality and yield was greatly influenced by drought stress, and so far, the mechanism of S. miltiorrhiza in response to drought stress is still unclear. Here, cDNA library ofS. miltiorrhiza under drought stress was analyzed based on digital gene expression profiling, and the differentially expressed genes （DEGs） was identified. Results of solexa sequencing showed that a total of 5 740 DEGs were screened out, of which 1 143 DEGs were up-regulated while 4 597 DEGs were down-regulated. GO enrichment analysis suggested that the DEGs were involved in catalytic activity and binding activity. Pathway analysis indicted that the up-regulated genes significantly enriched in flavonoid biosynthesis pathway, ribosomal peptide synthesis （RPS）, phenyl acid biosynthesis pathway, cysteine and methionine metabolic pathway, and plant hormone biosynthesis pathway. Meanwhile, the down-regulated genes mostly enriched in glycosphingolipid synthesis pathway, glycosaminoglycan degradation pathway and porphin, and chlorophyll metabolic pathway. Nine DEGs were selected randomly for qRT-PCR assay and the result was consistent with thatof DGE detection. This study lays a foundation for the further study of molecular mechanism in response to drought stress, and paves the way for drought-response gene screening ofS. miltiorrhiza.