Page 122 - 《广西植物》2023年第2期
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3 1 6                                  广  西  植  物                                         43 卷
                 performance liquid chromatography. Based on the reported CHI gene of Pueraria montana var. lobataꎬ the PtCHI gene
                 from P. montana var. thomsonii was isolated by homologous cloning methodꎬ and the protein was expressed in vitro. At
                 the same timeꎬ the location of the PtCHI gene was studied in Arabidopsis thaliana protoplasts. The results were as
                 follows: (1) The content of puerarin in P. montana var. lobata was significantly higher than the P. montana var.
                 thomsoniiꎬ and the content of total flavonoids was also higher but not significant. (2) The gene PtCHI was successfully
                 isolated from P. montana var. thomsonii. The gene was 742 bp in lengthꎬ containing a complete ORF frame of 672 bpꎬ
                 encoding 223 amino acidsꎬ and had up to 99% homology with P. montana var. lobata. (3) This study found that the
                 expression of CHI gene in P. montana var. thomsonii was stem>root>leafꎬ P. montana var. lobata was root>stem>
                 leaf. The expression of CHI gene from P. montana var. lobata was significantly higher than P. montana var. thomsonii

                 besides in leaves. (4) Through the online tool prediction analysisꎬ PtCHI was found to be stable hydrophilic protein and
                 the size was 27.8 kD. The secondary and tertiary structures were based on α ̄helixꎬ with 25 phosphorylation sitesꎬ closely
                 relating P. montana var. lobataꎬ Glycine max and Glycyrrhiza uralensisꎬ and were more likely to interact with F3H2ꎬ
                 F3Hꎬ 4CL4ꎬ DFR2 and CHS. (5)At the same timeꎬ the protein of PtCHI was successfully induced and isolated in vitroꎬ
                 with a single protein of 27.8 kD. (6) Through the Arabidopsis thaliana protoplasts revealed that PtCHI was mainly
                 located in the chloroplasts. This study further analyzed the difference in flavonoids in P. montana var. lobata and
                 P. montana var. thomsoniiꎬ as well as provides the reference for the functional verification of P. montana var. thomsonii
                 PtCHI and the research on the mechanism of isoflavone metabolism.
                 Key words: Pueraria montana var. thomsoniiꎬ PtCHIꎬ cloningꎬ prokaryotic expressionꎬ subcellular localization




                粉葛(Pueraria montana var. thomsonii) 为豆科        FhCHI1、FhCHI2、FhCHI3、FhCHI4、FhCHI5 蛋白ꎬ并
            蝶形花亚科葛属藤本植物ꎬ茎基部木质且具有肥厚                             通过酶活检测得出 FhCHI2 和 FhCHI5 具有活性ꎬ能
            的块状根ꎬ在我国广泛分布( 中国植物志ꎬ1995)ꎮ                         催化柚皮素查尔酮形成柚皮素ꎬ而 FhCHI3、FhCHI4
            其主要活性成分包括异黄酮类化合物葛根素、大豆                             没有活 性ꎻ 同 时ꎬ 在 拟 南 芥 中 异 源 表 达 FhCHI1、
            苷元、染料木素和异甘草素等ꎬ以及皂苷类物质皂                             FhCHI2、FhCHI5 能恢复 CHI 突变体拟南芥的花色
            角精醇、槐二醇和大豆苷醇等( 楚纪明等ꎬ2015)ꎮ                         苷和黄酮醇代谢ꎬ并能使植株幼苗的生长点恢复为
            另外ꎬ粉葛中还富含维生素 C、蛋白质、还原糖、淀粉                          紫色、种皮颜色变回棕色ꎻ而 FhCHI3、FhCHI4 则不
            和膳食纤维等营养成分(李桂花等ꎬ2021)ꎮ 粉葛作                         能恢复突变体的表型及花色苷和黄酮醇代谢ꎮ 郭
            为“药食同源”作物ꎬ因其淀粉含量高而常被加工成                            晋雅(2011)将紫心甘薯 IbCHI 基因转化至拟南芥突
            葛根粉、葛根薯片、葛根糕、葛根酒等系列商品ꎬ前                            变体中ꎬ发现紫心甘薯 IbCHI 基因能使突变体拟南
            人研究表明粉葛具有解热、抗病毒、降血糖血脂血                             芥(tt5)种皮颜色由浅黄色恢复到野生型的深棕褐
            压、保肝护肝、抗肿瘤、改善肾功能等作用(尚小红                            色ꎻ强光处理下突变体植株的叶片荧光参数 Fv / Fm

            等ꎬ2021ꎻ于钦辉等ꎬ2021)ꎮ                                 和 Yield 迅速降低ꎬ而转 IbCHI 的植株和野生型植株
                 查尔酮异构酶( chalcone isomeraseꎬ CHI) 是异           变化较慢ꎬ表明 IbCHI 能使突变体恢复至与野生型
            黄酮代谢途径中的一个关键酶ꎬ其酶活对植物体内                             植株一样的抵抗强光的效果ꎻ干旱处理后突变体植
            黄酮的积累起到重要作用ꎬ从而对植物的抗逆、花                             株萎蔫ꎬ而转 IbCHI 的植株和野生型植株的枯萎程

            色等存在关联(李琳玲等ꎬ2008ꎻ周发俊等ꎬ2008)ꎮ                       度较低ꎮ 何则铭 (2011) 的研究结果表明在 NaCl
            CHI 是个超基因家族ꎬ现主要分为 Type I、Type Ⅱ和                   (150 mmol  L ) 处 理 下ꎬ 过 表 达 GmCHI4A 和
                                                                              ̄1
            Type Ⅲ三个类型ꎬ大部分植物的 CHI 基因属于 Type                    GmCHI4B 的大豆发状根耐盐性高于对照ꎬ并且转基
            IꎬType Ⅱ一般只存在于豆科植物且该类型由 Type I                     因株系中的 GmSOD1 和 GmSOS1 表达量以及发状根
            演化而来ꎬType Ⅲ主要为真菌和细菌中的类 CHI 蛋                       中的异黄酮含量显著高于对照ꎮ 郭丹丹(2019) 研
            白家族(张党权等ꎬ2007ꎻ梁瓴婕ꎬ2016)ꎮ 目前ꎬCHI                    究表明红花 CtCHI1 基因定位于细胞核中ꎮ 李红艳
            基因已在多种植物中被成功分离并做了功能验证ꎮ                             (2019)研究发现丹参 SmCHI 基因不仅定位在烟草
            梁瓴 婕 ( 2016 ) 在 体 外 成 功 分 离 到 香 雪 兰 的              表皮细胞的高尔基体、 质膜和细胞核上ꎬ而且在内
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