我国新记录绿潮物种Ulva laetevirens的比较叶绿体基因组学研究  

COMPARATIVE CHLOROPLAST GENOME ANALYSIS OF NEW-GREEN TIDE CAUSATIVE SPECIES IN CHINA:ULVA LAETEVIRENS

作　　者：王静[1,2,3] 王毅超 王洪淑[1,2,3] 刘峰 陈楠生 WANG Jing;WANG Yi-Chao;WANG Hong-Shu;LIU Feng;CHEN Nan-Sheng(CAS Key Laboratory of Marine Ecology and Environmental science,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China;Functional Laboratory for Marine Ecology and Environmental science,Pilot National Laboratory for Marine Science and Technology(Qingdao),Qingdao 266237,China;Center for Ocean Mega-Science,Chinese Academy of Sciences,Qingdao 266071,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院海洋研究所海洋生态与环境科学重点实验室,青岛266071 [2]青岛海洋科学与技术试点国家实验室海洋生态与环境科学功能实验室,青岛266237 [3]中国科学院海洋大科学研究中心,青岛266071 [4]中国科学院大学,北京100049

出　　处：《海洋与湖沼》2021年第5期1201-1213,共13页Oceanologia Et Limnologia Sinica

基　　金：山东省支持青岛海洋科学与技术试点国家实验室重大科技专项,2018SDKJ0504-2号;中国科学院战略性先导科技专项(B类),XDB42000000号;中国科学院率先行动“百人计划”;泰山学者特聘专家计划;源头创新计划(人才发展专项-第五批创业创新领军人才研发补助(19-3-2-16-zhc);中国科学院前沿科学重点研究项目,QYZDB-SSW-DQC023号;山东省重大科技创新工程项目,2019JZZY020706号。

摘　　要：在全球范围内广泛暴发的石莼属绿潮既包括大规模暴发的跨海域绿潮,也包括小规模暴发的局地绿潮。我国有关绿潮致灾物种的研究对象主要集中于黄海绿潮浒苔,而针对局地绿潮致灾物种的研究尚处于起步阶段。针对局地绿潮物种的鉴定和分布调查是有效预防和监测潜在大规模绿潮暴发的重要环节。本文对2020年11月初于山东烟台第一海水浴场暴发的石莼属绿潮进行了初步研究。经随机采样获得了12株藻体,根据tufA分子标记初步将其中11株鉴定为Ulva laetevirens。本研究完成了U.laetevirens的一个代表性株系CNS00533的叶绿体基因组构建和解析。叶绿体基因组为110889 bp,含有71个蛋白编码基因、27个tRNA基因和3个rRNA基因(rrl、rrn和rrn5)。烟台海域U.laetevirens株系叶绿体基因组基因组成和排列顺序与爱尔兰海域U.laetevirens株系MT179351完全一致,DNA序列相似性为99.8%,进一步证明CNS00533为U.laetevirens。此外,U.laetevirens的烟台株系与爱尔兰株系的叶绿体基因组也存在差异,烟台株系比爱尔兰株系多了5个I型内含子和1个II型内含子,导致叶绿体基因组长度增加7 kb。CNS00533与U.rigida MT179352叶绿体基因组之间存在多个不同的长片段插入序列(763-2346 bp),DNA序列相似性也较低(93.1%);与U.australis MT179348相比差异更大,存在一个较大(覆盖45个基因)的基因组反转事件。在基于71个蛋白编码基因的遗传进化树中,CNS00533与U.laetevirens MT179351聚类在一枝,与U.rigida MT179352遗传距离较近,与U.australis MT179348的遗传距离很远,表明U.laetevirens、U.rigida和U.australis为石莼属的3个不同物种。2020年11月烟台海域局地绿潮事件的原因种U.laetevirens在我国近海绿潮事件中首次报道,本研究对该物种的分子进化分析将有助于对我国近海绿潮监测、物种鉴定提供数据支持和理论依据。Green tides caused by Ulva species have occurred for many years in the world.Some of them are large in scale across different ocean regions,while others are local.A green tide event occurred in early November,2020 in the No.1 Bathing Beach,Yantai,Shandong,East China was investigated.Twelve algae samples were randomly collected,of which 11 were identified as Ulva laetevirens according to the molecular marker tufA.The full-length chloroplast genome of U.laetevirens CNS00533 was constructed.The genome is 110889 bp in size,containing 71 protein coding genes,27 tRNA genes,and 3 rRNA genes(rrl,rrn,and rrn5).The chloroplast genome of CNS00533 and the U.laetevirens MT179351 genome have high sequence identity(99.8%).They also have identical number of genes and perfect colinearity,and showed substantial differences of genome between two U.laetevirens strains.The chloroplast genome of CNS00533 had five type-I introns and one type-intron that are absent in the Irish strain,resulting in an increase of 7 kb in chloroplastⅡgenome length difference in-between.In contrast,the chloroplast genome of CNS00533 and the U.rigida MT179352 chloroplast genome had low sequence identity(93.1%)and large number of long insertion/delection(ranging 763-2346 bp).Large genomic differences were observed between the chloroplast genome of CNS00533 and U.australis(MT179348),including an inversion that covered 45 genes.In the phylogenetic tree based on 71 protein coding genes of Ulva species,CNS00533 and U.laetevirens MT179351 joined in one cluster,while U.rigida MT179352,and U.australis MT179348 were clearly in another clade,indicating that U.laetevirens,U.rigida,and U.australis are three different species of the Ulva genera.Therefore,U.laetevierens was found to be a new green-tide causative species in China ocean regions.The molecular evolution analysis of this species presented in this paper enriched our findings and shall help effective monitoring green tides in coastal waters of China.

关 键 词：局地绿潮 石莼 叶绿体 分子进化 

分 类 号：X173[环境科学与工程—环境科学] P76[天文地球—海洋科学]