茶树花Cu/Zn-SOD酶活性及其基因表达分析

王梦馨 吴国火 崔林 韩宝瑜

摘  要：為研究Cu/Zn-SOD基因在茶树花不同发育阶段、不同品种间的表达规律以及Cu/Zn-SOD基因表达量与酶活性之间的关系，本研究将‘龙井43品种茶树花分为4个发育阶段，选择15个品种的茶树花为研究对象，采用实时荧光定量PCR技术对3个Cu/Zn-SOD基因表达水平进行定量分析，同时测定Cu/Zn-SOD酶活性。结果表明：在茶树花的4个发育阶段中，第4阶段Cu/Zn-SOD酶活性最低，与其他3个阶段具有显著差异;不同品种的茶树花Cu/Zn-SOD酶活性有较大差异，其中‘紫鹃茶树花Cu/Zn-SOD酶活性最高，其次是‘黄金芽和‘白叶1号，‘黄观音的Cu/Zn-SOD酶活性最低。茶树花不同发育阶段中Cu/Zn-SOD基因表达水平存在较大差异，细胞质型Cu/Zn-SOD1基因表达水平远高于叶绿体型Cu/Zn-SOD2和过氧化物酶体Cu/Zn-SOD3;不同品种茶树花Cu/Zn-SOD基因表达水平有较大差异，Cu/Zn-SOD1基因在‘黄牡丹茶树花中表达量最高，Cu/Zn-SOD2基因在‘白叶1号和‘黄观音茶树花中表达量最高，Cu/Zn-SOD3基因在‘紫鹃茶树花中的表达量最高。相关性分析得知‘龙井43茶树花不同发育阶段Cu/Zn-SOD酶活性与Cu/Zn-SOD基因表达量之间的相关性不明显，而不同品种茶树花的Cu/Zn-SOD酶活性与Cu/Zn-SOD3基因表达量存在显著相关性。本研究初步明确了Cu/Zn-SOD酶活性较高的茶树品种和茶树花适宜的采摘时间，为茶树花SOD进一步研究提供参考。

关键词：茶树花;Cu/Zn-SOD基因;实时荧光定量PCR;Cu/Zn-SOD酶活性;‘龙井43中图分类号：S571.1      文献标识码：A

Enzyme Activity Characteristics and Expression ofCu/Zn-SODGene in Tea Flowers

WANG Mengxin， WU Guohuo， CUI Lin， HAN Baoyu^*

College of Life Sciences， China Metrology University / Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine， Hangzhou， Zhejiang 310018， China

Abstract：In order to study the expression characteristics ofCu/Zn-SODgene in the flowers within different developmental stages and various cultivars of tea plant flowers， and to discuss the correlationship between the expression ofCu/Zn-SODgene and its enzyme activity， four developmental stages of cultivar ‘Longjing 43 tea flower and 15 tea plant cultivars of fresh flowers were studied. The expression of threeCu/Zn-SODgenes was quantitatively analyzed by real-time fluorescent quantitative PCR techniques， and the enzyme activity of the three Cu/Zn-SOD was also determined simultaneously. The lowest Cu/Zn-SOD enzyme specific activity was found in the fourth stage， and the difference was significant when compared with the other developmental stages. The specific activity of Cu/Zn-SOD enzyme in different cultivars of tea flowers was significantly different. The Cu/Zn-SOD enzyme specific activity of ‘Zijuan tea flower was the highest， followed by ‘Huangjinya and ‘Baiye 1. The activity of Cu/Zn-SOD enzyme of ‘Huangguanyin tea flower was the lowest. The expression level ofCu/Zn-SODdiffered among the developmental stages， and the expression of cytoplasmicCu/Zn-SOD1gene was much higher than those of chloroplast typeCu/Zn-SOD2and peroxisomeCu/Zn-SOD3. The expression ofCu/Zn-SODin different cultivars was significantly different.Cu/Zn-SOD1had the highest expression in cultivar ‘Huangmudan tea flower，Cu/Zn-SOD2gene had the highest expression in cultivars ‘Baiye 1 and ‘Huangguanyin tea flowers， andCu/Zn-SOD3gene had the highest expression in cultivar ‘Zijaun tea flowers. The result of correlation analysis showed that the specific activity of Cu/Zn-SOD had no correlation withCu/Zn-SOD gene expression in different developmental stages of ‘Longjing 43 tea flowers， but had considerable correlation withCu/Zn-SOD3 gene expression in different tea cultivars. In this study， both tea cultivars and suitable plucking stage with high Cu/Zn-SOD activity were preliminarily expounded， which would provide references for the further research on SOD.

Keywords： tea plant flowers;Cu/Zn-SODgene; real time fluorescence quantitative PCR; Cu/Zn-SOD enzyme activity; cultivar ‘Longjing 43

DOI： 10.3969/j.issn.1000-2561.2020.06.014

茶树花是茶树（Camellia sinensis（L.） O. Kuntze）的有性生殖器官^[1]，含有丰富的蛋白质、氨基酸、香精油、茶多糖、维生素等营养和功能成分及超氧化物歧化酶（superoxide dismutase，SOD）等活性物质^[2-6]，对人体具有解毒、降脂、降糖、保护肠胃、增强免疫力和抗氧化等功效^[7-8]。……