基于转录组鉴定楸子叶片和根系干旱响应基因

Identification of Drought-responsive Genes in Leaves and Roots of Malus prunifolia Based on Transcriptome

利用RNA-Seq技术研究楸子根、叶组织响应干旱胁迫的差异表达基因(DEGs),为探讨苹果砧木不同组织的抗旱分子机制提供理论依据。结果表明,与对照相比,在干旱胁迫下根、叶组织的基因表达数被抑制。叶片得到2211个DEGs,其中1128个上调,1083个下调;根系得到4996个DEGs,其中1810个上调,3186个下调。叶片DEGs显著富集于植物激素信号转导、淀粉和蔗糖代谢、氨基酸和核苷酸糖代谢以及半乳糖代谢等通路,叶片重要功能基因与ABA胁迫响应、IAA内稳态、肌醇和棉子糖合成关键酶、硝酸根转运蛋白、伸展蛋白、铁蛋白和脱水蛋白等相关。根系DEGs显著富集于苯丙烷类生物合成、植物病原菌互作、苯丙氨酸代谢、谷胱甘肽代谢以及萜类(双萜,倍半萜和三萜)生物合成等通路,重要表达基因与木质素、类胡萝卜和萜类次生代谢物、环核苷酸门控离子通道、钙离子和MAPK信号途径等相关。这些干旱响应基因在抗旱反应中可能对维持根、叶组织特异功能起到重要的作用。

The differentially expressed genes(DEGs)in leaf and root tissues of Malus prunifolia responsing to drought stress were analyzed by RNA-Seq technology,to explore the molecular resistance mechanism of different tissues in apple rootstock.The results showed that the total number of genes expression in leaf and root was inhibited under drought stress compared to the contrast condition.Through differential analysis of genes between the control and drought treated groups,a total of 2211 and 4996 DEGs were found in leaf and root,of which1128 and 1810 were up-regulated,and 1083 and 3186 were down-regulated in leaf and root tissues,respectively.Leaf DEGs were significantly enriched in plant hormone signal transduction,starch and sucrose metabolisms,amino sugar and nucleotide sugar metabolism,and galactose metabolism,in which some key functional genes in leaf tissues were mainly involved in ABA stress response,IAA homeostasis,key enzymes in inositol and raffinose synthesis,nitrate transporters,expansin,ferritin,and dehydrin proteins.Root DEGs were significantly enriched in phenylpropanoid biosynthesis,plant-pathogen interaction,phenylalanine metabolism,glutathione metabolisms,and terpenoids(diterpenoid,sesquiterpenoid and triterpenoids)biosynthesis,and these important drought response genes of root tissue were involved in lignans,carotenoids,terpenoid secondary metabolites,cyclic nucleotide-gated ion channel,calcium and MAPK signal pathways.Conclusively,these drought response genes play a crucial role in drought resistance of tissue-specific function of plants.