Page 63 - 《广西植物》2025年第1期
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1 期 廖晓童等: 海滨猫尾木叶绿体基因组特征及编码基因 psbB 对冷胁迫的响应 5 9
( 1. Life Science and Technology Collegeꎬ Key Laboratory of Conservation and Restoration of Mangrove Ecosystemꎬ Engineering and Technological
Research in Protection and Utilization of Mangrove Rare and Endangered Speciesꎬ Lingnan Normal Universityꎬ Zhanjiang 524048ꎬ Guangdongꎬ
Chinaꎻ 2. College of Life Sciencesꎬ Ministry of Education Key Laboratory for Ecology of Tropical Islandsꎬ Key Laboratory of
Tropical Animal and Plant Ecology of Hainan Provinceꎬ Hainan Normal Universityꎬ Haikou 571158ꎬ China )
Abstract: Low temperature is an important obstacle to the ecological restoration of endangered mangrove plant
Dolichandrone spathacea. Plant chloroplasts and their coding genes closely respond to cold stress. Analyzing chloroplast
genome characteristics and understanding the molecular response patterns of psbB genes under cold stress can help
protect and restore this species. To reveal the chloroplast genome informationꎬ this study sequenced the total DNA of
D. spathacea using the Illumina NovaSeq sequencing platformꎬ and then annotated and functionally analyzed the
assembled chloroplast genome. In the meantimeꎬ the changes of psbB gene in D. spathacea seedlings under different
temperatures were investigatedꎬ and physiological parameters such as total chlorophyllꎬ malondialdehydeꎬ prolineꎬ total
phenolsꎬ soluble proteinꎬ and soluble sugar were detected in this study. Further the expression value of psbB gene was
detected using fluorescence quantitative PCR experiment. The results were as follows: (1) The chloroplast genome of
D. spathacea exhibited a typical tetrad structure with the length of 159 139 bpꎬ and the GC content of 37.9%. It encoded
a total of 133 genesꎬ including protein ̄coding genes (88)ꎬ tRNA genes (37) and rRNA genes (8). (2) Phylogenetic
analysis revealed that D. spathacea did not form a monophyletic group but instead clustered with 8 other Bignoniaceae
speciesꎬ with a support rate of 100%. (3) Under cold stressꎬ the contents of total chlorophyll in the leaves of the
D. spathacea seedlings decreased with the decrease of treatment temperatureꎬ while the contents of total phenolsꎬ
malondialdehydeꎬ prolineꎬ soluble protein and soluble sugar and relative expression values of psbB gene in the seedling
leaves increased with the decrease of treatment temperature. In summaryꎬ the chloroplast genome characteristic of
D. spathacea is highly conservative in Bignoniaceae family. Under cold stressꎬ the total chlorophyll synthesis of the plant
is inhibitedꎬ and the synthesis of osmoregulatory substances is affected. At the same timeꎬ the psbB gene is involved in
molecular regulation under plant cold stress. The above results provide a preliminary basis for molecular assisted breeding
to improve the cold resistance of endangered mangrove plants.
Key words: Dolichandrone spathaceaꎬ chloroplast genomeꎬ phylogenesis analysisꎬ cold stressꎬ physiological indicatorsꎬ
psbB gene
海滨猫尾木( Dolichandrone spathacea) 隶属于 ( Wang XP et al.ꎬ 2022)ꎬ低温胁迫会对植物叶绿体
紫葳科( Bignoniaceae) 猫尾木属( Dolichandrone)ꎬ 结构、光合色素含量产生影响(Li WJ et al.ꎬ 2022)ꎮ
是我国典型的半红树植物( 胡启明等ꎬ1987)ꎮ 其 叶绿体拥有相对独立的遗传体系(邢少辰和 Clarkeꎬ
自然分布于海南和广东两省ꎬ2006 年被列入«海南 2008)是植物特有的细胞器ꎬ对植物的生长发育起
省重点保护野生植物名录»(张颖等ꎬ2021)ꎮ 该植 着重要作用(Llorente et al.ꎬ 2021)ꎮ 在植物分类与
物拥有重要的生态和药用价值( 田广红等ꎬ2011)ꎮ 物种水平的系统发育等研究中ꎬ叶绿体基因组由于
作为中国和东南亚地区传统的药用植物ꎬ海滨猫 大小适中ꎬ编码区序列相对保守ꎬ结构比较稳定ꎬ进
尾木在医疗上已被用作治疗糖尿病、癌症和其他 化速率 相 对 较 低 等 优 点 而 受 到 重 视 ( Xu et al.ꎬ
疾病的药物( Akashi & Gojobortꎬ 2002)ꎮ 但是ꎬ海 2001)ꎮ 随着测序技术的快速发展ꎬ已公布了超过 1
滨猫尾木的濒危状态限制了其生态价值和药用价 000 种高等植物的叶绿体基因组全序列(Liu et al.ꎬ
值的深入利用ꎮ 红树植物通常生长在热带和亚热 2022)ꎮ 其中ꎬ对紫葳科多种植物的叶绿体基因组
带的海岸潮间带ꎮ 然而ꎬ近年来频繁发生的低温 特征进行了全面分析和报道(Nazareno et al.ꎬ 2015ꎻ
灾害ꎬ给包括海滨猫尾木在内的红树植物带来了 Thode & Lohmannꎬ 2019ꎻ Yaradua & Yessoufouꎬ
短期、突然的低温伤害( 黄雪松ꎬ2021)ꎬ增加了其 2022ꎻ Li F et al.ꎬ 2022)ꎬ但目前尚未发现有关海滨
生态修复工作的难度ꎮ 猫尾木的相关研究报道ꎮ
温度是影响植物生长发育的重 要 影 响 因 子 叶绿体编码基因 psbB 属光系统Ⅱ相关基因ꎬ