基于苋菜转录组的TCP基因家族成员鉴定及表达分析

Transcriptome-based Identification and Expressions of Amaranth TCP Gene Family

【目的】基于大红苋菜转录组数据库,对苋菜TCP基因家族成员进行筛选鉴定,为深入探讨苋菜TCP基因家族对苋菜生长发育及非生物胁迫响应提供参考。【方法】在转录组数据库中,筛选鉴定TCP基因家族成员,并对其进行生物信息学分析;在不同条件处理下培养苋菜幼苗,并利用qRT-PCR技术分析其在不同处理下的表达模式。【结果】苋菜TCP基因家族有14个成员,全部定位于细胞核;AtrTCP蛋白质长度在230~721 aa区间内,预测相对分子量为25.25~78.57 kD,等电点为6.15~9.45,包含15个保守基序;除AtrTCP11为稳定蛋白外,其余均为不稳定蛋白;miRNA预测到两个AtrTCP家族成员AtrTCP2和AtrTCP6为miR319靶基因。qRT-PCR结果显示:在盐溶液不同浓度(0、50、100、200 mmol·L^(-1))处理下,该基因家族具有不同的表达模式;在蓝光处理下,AtrTCP10基因表达量上调达到了显著水平;AtrTCP2、AtrTCP3、AtrTCP8、AtrTCP9、AtrTCP11和AtrTCP13表达量下调达到了显著水平;在不同铵硝比(0∶0、0∶10、3∶7、5∶5、7∶3、10∶0)处理下,TCP基因家族各成员表达模式不同,其中,AtrTCP3参与整个氮代谢过程;在苋菜各部位进行qRT-PCR分析发现:AtrTCP3、AtrTCP12在叶片中高表达,其余家族成员均在根部的表达量较高。【结论】在不同条件处理下,苋菜TCP基因家族各成员表达模式不同,表明苋菜TCP基因家族各成员可能广泛参与非生物胁迫。

【Objective】 Members of the amaranth TCP gene family were identified based on the transcriptome database for an in-depth understanding on the roles they associated with the growth, development, and abiotic stress of the plant.【Method】 Members of the TCP gene family were identified by screening the transcriptome database on Dahong amaranth(Amaranthus tricolor L.) for a bioinformatics analysis. Amaranth seedlings were cultured under different conditions and their expressions under different treatments analyzed by qRT-PCR. 【Results】 Amaranth TCP gene family has 14 members, all localized in the nucleus. The length of AtrTCP protein was in the range of 230–721 aa, the predicted relative molecular weight was25.25–78.57 kD, the isoelectric point was 6.15–9.45, and it contained 15 conserved motifs. Except AtrTCP11, which was stable protein, all the other proteins were unstable. Two AtrTCP family members, AtrTCP2 and AtrTCP6, were predicted as miR319target genes by miRNA. qRT-PCR showed differentiated expressions of the family members under salt solutions of varied concentrations(i.e., 0, 50, 100, and 200 mmol·L). The expression of the upregulated AtrTCP10 reached a significant level under blue light, and so did those of the downregulated AtrTCP2, AtrTCP3, AtrTCP8, AtrTCP9, AtrTCP11, and AtrTCP13.Under different concentrations of ammonium nitrate ratio(0∶0, 0∶10, 3∶7, 5∶5, 7∶3, 10∶0) treatment, the expressions of the TCP genes differed. AtrTCP3 was shown to be involved in the entire nitrogen metabolism process. In tissues of amaranth,AtrTCP3 and AtrTCP12 were highly expressed in leaves, while the others in roots. 【 Conclusion】 Depending on the treatments, the expressions of the amaranth TCP gene family members differed. It suggested a broad spectrum of involvements by the members associated with abiotic stresses on amaranth.