水稻分蘖期氮素应答的转录组动态分析

Dynamic Transcriptome Analysis of Rice Response to Nitrogen Treatment at Tillering Stage

氮素是水稻生长发育必需的大量营养元素,通过探索水稻分蘖期对氮的转录响应,筛选氮素应答基因用于培育氮素利用率高的水稻品种,同时为水稻的精准栽培提供转录组学指导。以五优稻4号为材料,于施氮后7,14,21 d分别收获了五优稻4号叶片,并进行动态转录组分析。氮素处理使分蘖期水稻叶片颜色加深,并检测到3870个差异表达基因(DEGs)。GO分析显示,这些基因主要参与了代谢过程、细胞过程、细胞组分、催化活性和结合等方面,KEGG分析表明,有22个DEGs与半乳糖代谢、氨基糖和核苷酸糖代谢、丙氨酸、天冬氨酸和谷氨酸代谢途径显著相关。另外,通过互作蛋白预测发现35个互作蛋白。上述代谢途径在分蘖期不同时间点对氮的应答是有差异的,在氮素处理后,前期应答的差异表达基因galA、galE(LOC_Os05g51670)、malZ主要参与半乳糖代谢途径;中期应答的差异表达基因HEXA_B、GNPNAT1、GlmS、UAP1、RGP、XYL4、AXS、UXS1、UGDH、RHM、galE(LOC_Os09g15420)和GAUT主要参与氨基糖和核苷酸糖代谢途径;后期应答的差异表达基因AsnB、ASL、NadB、GOT2、GLT1和GlnA主要参与丙氨酸、天冬氨酸和谷氨酸的代谢途径,这些结果表明,上述基因在水稻不同生育进程中对氮素应答有时间上的差异。

Nitrogen is a macronutrient element necessary for the growth and development of rice.By exploring the transcriptional response of rice to nitrogen at tillering stage,screening of nitrogen response genes was used to cultivate rice varieties with high nitrogen use efficiency,and at same time provide precise cultivation of rice transcriptomics guidance for rice cultivation.Using Wuyoudao 4 as the material,the leaves of Wuyoudao 4 were harvested 7,14,21 d after nitrogen application,and the dynamic transcriptome analysis was performed.Nitrogen treatment deepened the color of rice leaves at tillering stage,and 3870 differentially expressed genes(DEGs)were detected.GO analysis showed that these genes were mainly involved in metabolic processes,cellular processes,cell components,catalytic activity and binding.KEGG analysis showed that 22 DEGs were significantly correlated with galactose metabolism,amino sugar and nucleotide glucose metabolism,alanine,aspartic acid and glutamic acid metabolism pathways.In addition,35 interacting proteins were detected through interacting protein prediction.The above metabolic pathways had different responses to nitrogen at different time points in the tillering stage.After nitrogen treatment,the differentially expressed genes galA,HK,galE(LOC_Os05g51670)and malZ in the early response were mainly involved in the galactose metabolism pathway;The differentially expressed genes HEXA_B,GNPNAT1,GlmS,UAP1,RGP,XYL4,AXS,UXS1,UGDH,RHM,galE(LOC_Os09g15420)and GAUT in the mid-term response were mainly involved in the metabolic pathways of amino sugar and nucleotide sugar;differences in the late response.The expressed genes AsnB,ASL,NadB,GOT2,GLT1 and GlnA were mainly involved in the metabolic pathways of alanine,aspartic acid and glutamate.These results indicated that the above DEGs play different roles in the response to varied nitrogen during rice development temporally.