Page 119 - 《广西植物》2023年第11期
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11 期                    刘保财等: 多花黄精种子萌发前后基因表达特征分析                                          2 0 7 9

                 Abstract: Polygonatum cyrtonema seeds have a comprehensive dormancy phenomenonꎬ and analyzing the changes of key
                 genes before and after seeds germination plays an important role in exploring seed physiology and breaking
                 dormancy. Based on high ̄throughput sequencing technology (Illumina HiSeq 2500)ꎬ the transcriptome sequencing and
                 bioinformatics analysis were carried out in four stages of P. cyrtonema seed germination with three biological
                 replicates. The results were as follows: (1) A total of 388 231 Transcripts and 178 319 Unigenes were obtained by de
                 novo assembly. (2) Among the 11 817 Unigenes with significant differences before and after germinationꎬ 6 405 were up ̄
                 regulated and 5 412 were down ̄regulated. (3) Significant difference genes were enriched and analyzed in the GO
                 enrichment analysisꎬ and the differential expression up ̄ and down ̄regulation Uningenes were main enriched in biological
                 process and molecular functionꎬ which were mainly involved in metabolic processes and catalytic activities. (4) KEGG
                 significant enrichment indicated that the differential expression genes were mainly enriched in ribosomeꎬ plant hormone
                 signal transductionꎬ starch and sucrose metabolism and other pathwaysꎻ the up ̄regulated differential genes were mainly
                 enriched in ribosome 231ꎬ plant hormone signal transduction 56ꎬ starch and sucrose metabolism 76 and othersꎻ the
                 down ̄regulated differential genes were mainly enriched in phenylpropanoid biosynthesis 48 plant hormone signal
                 transduction 48ꎬ starch and sucrose metabolism 48ꎬ and other pathwaysꎻ a total of 40 differential genes were involved in
                 the synthesis of auxin pathway key enzymes. Genes encoding sucrose phosphate synthase were down ̄regulated and genes
                 encoding glycogen phosphorylase were up ̄regulated in starch and sucrose metabolic pathways. The above results
                 preliminarily identify that plant hormone signal transduction and starch and sucrose metabolism play a key role before and
                 after the germination of P. cyrtonema seedsꎬ and clarify the key genes involved in these two pathwaysꎬ which provide a
                 reference for further research on the physiologyꎬ reproduction and breeding of P. cyrtonema seeds.
                 Key words: Polygonatum cyrtonemaꎬ seedsꎬ before and after germinationꎬ genesꎬ expression characteristics


                多花黄精( Polygonatum cyrtonema) 属于黄精              茎秦艽种子萌发前、萌发中及萌发后 3 个阶段的转
            属多年生草本植物( Chen et al.ꎬ 2000)ꎬ为习用的                  录组分析结果表明ꎬ光照条件和激素水平为粗茎秦
            药食两用物种(Li et al.ꎬ 2022ꎻ Wu et al.ꎬ 2022)ꎬ          艽种子萌发过程的重要调控因子(杨晓等ꎬ 2021)ꎻ
            具有补气养阴、健脾、润肺、益肾的功效ꎬ用于治疗                            鸡骨草种子具有极低的发芽率ꎬ通过赤霉素处理ꎬ
            脾胃气虚、体倦乏力、胃阴不足、口干食少、肺虚燥                            编码 CYP78A5、Bg7s、GA ̄20 ̄ox、rd22、MYB4、LEA、
            咳等疾病(国家药典委员会ꎬ 2020)ꎮ 现代药理研                         CHS 等 蛋 白 的 基 因 发 生 了 上 调 ( Shimizu et al.ꎬ
            究表明ꎬ多花黄精含有多糖、生物碱、黄酮等生化                             2022)ꎻ同属黄精种子的转录组学研究揭示了变温
            成分ꎬ具有降血糖、抗疲劳、抗炎、抗菌和调节免疫                            可打破种子上胚轴的休眠机制ꎬ明确植物激素、染
            等作用(Li et al.ꎬ 2018ꎬ 2020ꎻ Gan et al.ꎬ 2022)ꎮ      色体修饰、DNA 甲基化、mRNA 降解、胚乳弱化和细
            随着人们对多花黄精的认知加深ꎬ其倍受青睐ꎬ栽                             胞壁结构相关的基因协同控制着黄精种子萌发、上
            培面积逐步扩大( 黄申等ꎬ 2020)ꎮ 多花黄精等药                        胚轴休眠和幼苗形成(Liao et al.ꎬ 2021)ꎮ 在黄精种
            用植物的种子存在后熟的生理现象ꎬ收获后需要                              子发育与休眠解除过程中ꎬ与种胚形态建成、多糖
            沙藏贮存ꎬ常规晒干后迅速降低种子的发芽率( 刘                            分解及蛋白质合成等相关的差异基因表达上调且
            保财等ꎬ 2015ꎻ 安瑞朋等ꎬ 2020)ꎬ而多花黄精种                      涉及多个代谢途径的相互作用ꎬ构成复杂的休眠解
            子苗的繁育对多花黄精的生产及其产业健康发展                              除调控网络(罗丽娜和向增旭ꎬ 2021ꎻ Zhang et al.ꎬ

            具有重要意义(刘保财等ꎬ 2017)ꎮ                                2022)ꎮ 然而ꎬ当前关于多花黄精种子的萌发过程
                 转录组测序技术已成为种子萌发( Chen et al.ꎬ                  的基因研究报道较少ꎬ尤其是对种子萌发具有关键
            2022)、 生物合成 ( Liu et al.ꎬ 2022ꎻ Song et al.ꎬ       作用的特征性表达通路与基因尚不清楚ꎬ阻碍了多
            2022)等关键基因发现的有效手段ꎮ 基于转录组方                          花黄精种子育苗、种子生理及其综合开发利用ꎮ 本
            法ꎬ对重楼种子休眠解除过程中差异基因的表达情                             研究利用转录组学方法ꎬ对多花黄精种子萌发过程
            况及相关代谢通路进行研究ꎬ明确重楼种子的休眠                             中的 4 个阶段开展了测序ꎬ拟探讨:(1)多花黄精种
            与脱落酸、赤霉素、生长素、油菜甾醇、细胞分裂素、                           子萌发后ꎬ哪些通路为关键通路ꎻ(2)这些关键通路
            乙烯、茉莉酸和水杨酸相关(Song et al.ꎬ 2022)ꎻ粗                  上哪些基因进行了显著变化ꎮ 为打破多花黄精种
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