Page 66 - 《广西植物》2024年第2期
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2 6 8                                  广  西  植  物                                         44 卷
                 purple stalk and green stalkꎬ and named as BjGSTF12. In this studyꎬ the bioinformatics characteristics of BjGSTF12
                 encoding protein and promoter were analyzedꎬ the expression level of BjGSTF12 and the relationship with total
                 anthocyanidin content were analyzed in B. juncea lines with purple stalk and green stalk. The results were as follow: (1)
                 BjGSTF12 genes from B. juncea were successfully clonedꎬ whose the full length of BjGSTF12 in genome and cDNA was
                 808 bp and 651 bpꎬ encoding a protein of 216 amino acids. The BjGSTF12 contained the typical domains of GST
                 proteinsꎬ namely GST_N and GST_C. Howeverꎬ their sequences of BjGSTF12 did not exhibit any differences between the
                 two lines of B. juncea. (2) BjGSTF12 was closely related to AtGSTF12 in Arabidopsisꎬ and both belonged to the φ
                 subfamily of GST family. (3) The BjGSTF12 promoter sequences were cloned from two Brassica juncea strains of green
                 stalk and purple stalkꎬ and they exhibited four base mutations/ insertions. Howeverꎬ the types and numbers of cis ̄acting
                 elements did not show obvious differences between the two strainsꎬ including nine MYB transcription factor binding
                 sitesꎬ one hormone response elementꎬ and three abiotic corresponding elements. (4) The total anthocyanidin content in
                 B. juncea of purple stalk was significantly higher than that in green stalk onesꎬ and the expression levels of BjGSTF12 in
                 two lines were found to be similar to the total anthocyanidin content in both lines. (5) Protein interaction network
                 analysis revealed that BjGSTF12 may interact with the key enzymes of anthocyanidin biosynthesisꎬ glycosylation
                 modificationꎬ and transporter proteins. In summaryꎬ BjGSTF12 is likely to play a key role in the accumulation of
                 anthocyanidin in B. juncea by regulating its biosynthesisꎬ modificationꎬ and transportation through interactions with other
                 proteins. This study provides a theoretical reference for further study on the function of GST and the mechanism of
                 anthocyanidin accumulation in B. juncea.
                 Key words: Brassica junceaꎬ GSTꎬ bioinformatics analysisꎬ expression analysisꎬ anthocyanidin accumulation




                谷 胱 甘 肽 转 移 酶 ( glutathione S ̄transferaseꎬ     异源物质或氧化产物结合ꎬ促进其代谢、隔离或清
            GSTꎬEC 2.5.1.1.8) 是一种具有多功能的超家族                     除ꎬ从而降 低 有 毒 物 质 对 细 胞 伤 害 ( 陈 秀 华 等ꎬ
            酶ꎬ广泛存在于生物界ꎬ主要催化还原型谷胱甘肽                             2013)ꎻ(2)参与调控植物对盐胁迫、重金属胁迫等
            (glutathioneꎬGSH)和疏水、亲电底物共价结合形成                    非生物胁迫条件下的抗逆能力( Lallement et al.ꎬ
            共轭物ꎬ将生物体内潜在的有毒物质和外来的有                              2014ꎻ邢磊等ꎬ2020ꎻ张创娟等ꎬ2022)ꎻ(3) 参与花
            害物质隔离在液泡或转移到质外体ꎬ从而达到解                              青素等次生代谢物的跨膜运输定位( Marrs et al.ꎬ
            毒目的(Cummins et al.ꎬ 2011ꎻ陈秀华等ꎬ2013ꎻ张               1995)ꎮ 玉米 Bronze ̄2 是研究发现的第一个在花
            雪等ꎬ2017)ꎮ 根据 GST 家族的基因结构、氨基酸                       青素积累中起重要作用的 GST 基因( Marrs et al.ꎬ
            序列相似性以及催化底物等性质的不同ꎬGST 家                            1995)ꎮ Bronze ̄2 的 同 源 基 因ꎬ 如 拟 南 芥 TT19

            族分为 7 个亚家族ꎬ分别为 φ(phiꎬF)、τ(tauꎬU)、ζ                 (GSTF12)(Sun et al.ꎬ 2012)、猕猴桃 AcGST1( Liu
            (zetaꎬZ)、θ( thetaꎬT)、λ( lambdaꎬL)、脱氢抗坏血            et al.ꎬ 2019)、棉花 GhGSTF12(Shao et al.ꎬ 2021)、
            酸还原酶( dehydroascorbate reductaseꎬDHAR) 和四          萝卜 RsGSTF12( Niu et al.ꎬ 2022) 等陆续被报道ꎬ

            氯 对 苯 二 酚 脱 卤 酶 ( tetrachlorohydroquinone          表明 GST 基因在花青素积累中的功能是高度保守
            dehalogenaseꎬTCHQD)ꎬ其中ꎬφ 和 τ 是植物所有特                的ꎮ 由此可见ꎬGST 家族成员在植物花青素积累

            有的 GST 类 型 ( Mohsenzadeh et al.ꎬ 2011)ꎮ GST        中发挥着重要作用ꎮ
            蛋白均包含 N 端和 C 端 2 个结构域ꎬ其中ꎬN 端为                          芥菜(Brassica juncea )是十字花科芸薹属作物ꎬ
            GSH 特异结合位点(G 位点)ꎬ该位点较保守ꎬC 端                        为世界重要的蔬菜、油料、调料作物ꎮ 在我国ꎬ芥菜
            包含结合疏水底物的结合位点( H 位点)ꎬ该位点                           可分为根、 茎、 叶、 薹四大类 16 个变种 ( 刘佩瑛ꎬ

            可变性较大(邢磊等ꎬ2020)ꎮ                                   1996)ꎬ除西藏等高寒山区外ꎬ芥菜在全国各地均有
                 目 前ꎬ 已 从 拟 南 芥 ( Mohsenzadeh et al.ꎬ          栽培(万正杰等ꎬ2020)ꎮ 随着生活水平的日益提高
            2011)、油菜( Wei et al.ꎬ 2019)、石榴( 刘龙博等ꎬ              与环境条件的变化ꎬ人们对芥菜品质和品种抗性提
            2021)等多个物种中分离鉴定了 GST 基因ꎬ其功能                        出了新要求(符梅等ꎬ 2022)ꎮ 培育紫色蔬菜品种对
            主要体现在以下三个方面:(1) 催化 GSH 与有毒                         提高蔬菜的经济价值和营养价值具有重要意义ꎮ
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