| 摘要: |
| 红藻真江蓠(Gracilaria vermiculophylla)是西北太平洋地区特有种，但在过去100年间它借助海运(太平洋牡蛎养殖)快速入侵到北美、欧洲和地中海等沿海栖息地，对当地的生物多样性、海洋环境和生态系统等造成重大影响。为从分子水平初步了解真江蓠成功入侵的潜在机制，我们对其入侵起源地——日本北部的真江蓠及非入侵种——绳状龙须菜(Gracilariopsis chorda)进行了同质园实验(common garden experiment)处理后的比较转录组研究，以探究该地区入侵属性不同的两种红藻间的基因表达差异。结果表明，真江蓠和绳状龙须菜共有unigene主要集中在核糖体、嘌呤和嘧啶代谢等通路。其中，在真江蓠中光系统II反应中心蛋白D1(photosystem II reaction center protein D1)、细胞色素P450单加氧酶(cytochrome P450 monooxygenase)和核酮糖1,5二磷酸羧化酶大亚基(Ribulose bisphosphate carboxylase large subunit, rbcL)等基因的表达量显著上调，而逆转录转座子蛋白(retrotransposon protein)、细胞壁相关的水解酶(cell wall-associated hydrolase)和金属离子转运蛋白Nramp5的表达既上调也下调。与光合作用过程相关基因的大量表达可能有助于真江蓠应对逆境胁迫，特别是光系统Ⅱ D1反应中心蛋白表达量升高可能有助于藻体修复光系统Ⅱ复合体，从而制造更多的有机物以备藻体生长所需。而金属离子转运蛋白Nramp5等的上调和下调则表明江蓠等红藻可能通过某些基因表达量的增减对不同的环境变动作出响应。总体而言，代谢过程中的资源再分配很可能是驱动真江蓠适应和耐受新的生境的主要分子机制。 |
| 关键词: 海藻入侵 环境适应 光合作用 转录调控 资源再分配 |
| DOI：10.11693/hyhz20231100258 |
| 分类号: |
| 基金项目:国家自然科学基金项目（面上项目，重点项目，重大项目） |
附件 |
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| COMPARATIVE TRANSCRIPTOMICS OF TWO RED SEAWEEDS: THE INVASIVE GRACILARIA VERMICULOPHYLLA AND THE NONINVASIVE GRACILARIOPSIS CHORDA |
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Ma Meng1, Xiang Jinxi1, Xue Kaixue2, Wang Gaoge3, Weinberger Florian4, Hu Zimin5
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1.Ocean School, YanTai University;2.Qingdao Municipal Marine Development Bureau in West Coast New Area;3.Institute of Evolution and Marine Biodiversity, College of Marine Life Sciences, Ocean University of China;4.Marine Ecology Division,GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel,Düsternbrooker Weg ,,Kiel,Germany;5.Yantai University
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| Abstract: |
| The red seaweed Gracilaria vermiculophylla is native to the Northwest Pacific. However, it widely colonized and expanded its range in the North American, European and Mediterranean habitats over the past 100 years via the aquaculture of the pacific oyster (Crassostreagigas), and considerably influenced local species diversity, coastal environment and ecosystem. To investigate the potential molecular mechanism underpinning the successful adaptation to new environments, we performed a comparative transcriptomics of the invasive G. vermiculophylla and the non-invasive red macroalga Gracilariopsis chorda from northern Japan where has been demonstrated as the original sources of G. vermiculophylla, with the aim to detect their gene-expression level of differences. Our results showed that the shared unigenes between G. vermiculophylla and G. chorda are mainly enriched in pathways such as ribosome, pyrimidine and purine metabolism. In comparison with G. chorda, the expression levels of cytochrome P450 monooxygenase, and ribulose bisphosphate carboxylase large subunit and photosystem Ⅱ D1 protein significantly up-regulated in G. vermiculophylla, whilst the retrotransposon protein, cell wall-associated hydrolase and metal transporter Nramp5 either up- or down-regulated. The abundant expression of genes related photosynthesis may help G. vermiculophylla to deal with environmental stresses. In particular, the high-level expression of photosystem Ⅱ D1 protein is vital to repair photosystem Ⅱ complex and produce more organic matter required for growth of seaweed. The up- and down-regulation of unigenes such as metal transporter Nramp5 may imply that G. vermiculophylla likely copes with different environmental changes via the increased or declined expression of some specific genes. These gene-expression signatures here provide primary insights for understanding how red macroalgae adapt to environmental changes. |
| Key words: seaweed invasion environmental adaptation transcriptional regulation photosynthesis resource reallocation |