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Xi L, Sun Y, Xu T, Wang Z, Chiu MY, Plouviez S, Jollivet D, Qiu J. Phylogenetic divergence and population genetics of the hydrothermal vent annelid genus
Hesiolyra
along the East Pacific Rise: Reappraisal using multi‐locus data. DIVERS DISTRIB 2022. [DOI: 10.1111/ddi.13653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Affiliation(s)
- Leyi Xi
- Department of Biology Hong Kong Baptist University Hong Kong China
| | - Yanan Sun
- Department of Biology Hong Kong Baptist University Hong Kong China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) Guangzhou China
- Department of Ocean Science The Hong Kong University of Science and Technology Hong Kong China
| | - Ting Xu
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) Guangzhou China
- Department of Ocean Science The Hong Kong University of Science and Technology Hong Kong China
| | - Zhi Wang
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences Xiamen University Xiamen China
| | - Man Ying Chiu
- Department of Biology Hong Kong Baptist University Hong Kong China
| | - Sophie Plouviez
- Department of Biology University of Louisiana at Lafayette Lafayette Louisiana USA
| | - Didier Jollivet
- Sorbonne Université‐CNRS, UMR 7144 Adaptation et Diversité en Milieu Marin, Equipe DyDiv Station Biologique de Roscoff Roscoff France
| | - Jian‐Wen Qiu
- Department of Biology Hong Kong Baptist University Hong Kong China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) Guangzhou China
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Thomas-Bulle C, Bertrand D, Nagarajan N, Copley RR, Corre E, Hourdez S, Bonnivard É, Claridge-Chang A, Jollivet D. Genomic patterns of divergence in the early and late steps of speciation of the deep-sea vent thermophilic worms of the genus Alvinella. BMC Ecol Evol 2022; 22:106. [PMID: 36057769 PMCID: PMC9441076 DOI: 10.1186/s12862-022-02057-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 08/05/2022] [Indexed: 11/10/2022] Open
Abstract
Background The transient and fragmented nature of the deep-sea hydrothermal environment made of ridge subduction, plate collision and the emergence of new rifts is currently acting to separate of vent populations, promoting local adaptation and contributing to bursts of speciation and species specialization. The tube-dwelling worms Alvinella pompejana called the Pompeii worm and its sister species A. caudata live syntopically on the hottest part of deep-sea hydrothermal chimneys along the East Pacific Rise. They are exposed to extreme thermal and chemical gradients, which vary greatly in space and time, and thus represent ideal candidates for understanding the evolutionary mechanisms at play in the vent fauna evolution. Results We explored genomic patterns of divergence in the early and late stages of speciation of these emblematic worms using transcriptome assemblies and the first draft genome to better understand the relative role of geographic isolation and habitat preference in their genome evolution. Analyses were conducted on allopatric populations of Alvinella pompejana (early stage of separation) and between A. pompejana and its syntopic species Alvinella caudata (late stage of speciation). We first identified divergent genomic regions and targets of selection as well as their position in the genome over collections of orthologous genes and, then, described the speciation dynamics by documenting the annotation of the most divergent and/or positively selected genes involved in the isolation process. Gene mapping clearly indicated that divergent genes associated with the early stage of speciation, although accounting for nearly 30% of genes, are highly scattered in the genome without any island of divergence and not involved in gamete recognition or mito-nuclear incompatibilities. By contrast, genomes of A. pompejana and A. caudata are clearly separated with nearly all genes (96%) exhibiting high divergence. This congealing effect however seems to be linked to habitat specialization and still allows positive selection on genes involved in gamete recognition, as a possible long-duration process of species reinforcement.
Conclusion Our analyses highlight the non-negligible role of natural selection on both the early and late stages of speciation in the iconic thermophilic worms living on the walls of deep-sea hydrothermal chimneys. They shed light on the evolution of gene divergence during the process of speciation and species specialization over a very long period of time. Supplementary Information The online version contains supplementary material available at 10.1186/s12862-022-02057-y.
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Shi Y, Yao G, Zhang H, Jia H, Xiong P, He M. Proteome and Transcriptome Analysis of Gonads Reveals Intersex in Gigantidas haimaensis. BMC Genomics 2022; 23:174. [PMID: 35240981 PMCID: PMC8892766 DOI: 10.1186/s12864-022-08407-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 02/22/2022] [Indexed: 11/19/2022] Open
Abstract
Sex has proven to be one of the most intriguing areas of research across evolution, development, and ecology. Intersex or sex change occurs frequently in molluscs. The deep-sea mussel Gigantidas haimaensis often dominates within Haima cold seep ecosystems, but details of their reproduction remain unknown. Herein, we conducted a combined proteomic and transcriptomic analysis of G. haimaensis gonads to provide a systematic understanding of sexual development in deep-sea bivalves. A total of 2,452 out of 42,238 genes (5.81%) and 288 out of 7,089 proteins (4.06%) were significantly differentially expressed between ovaries and testes with a false discovery rate (FDR) <0.05. Candidate genes involved in sexual development were identified; among 12 differentially expressed genes between sexes, four ovary-biased genes (β-catenin, fem-1, forkhead box L2 and membrane progestin receptor α) were expressed significantly higher in males than females. Combining histological characteristics, we speculate that the males maybe intersex undergoing sex change, and implied that these genes may be involved in the process of male testis converting into female gonads in G. haimaensis. The results suggest that this adaptation may be based on local environmental factors, sedentary lifestyles, and patchy distribution, and sex change may facilitate adaptation to a changing environment and expansion of the population. The findings provide a valuable genetic resource to better understand the mechanisms of sex change and survival strategies in deep-sea bivalves.
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Affiliation(s)
- Yu Shi
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou, 510301, China.,Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, China
| | - Gaoyou Yao
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou, 510301, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hua Zhang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou, 510301, China.,Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, China
| | - Huixia Jia
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou, 510301, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Panpan Xiong
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou, 510301, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Maoxian He
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou, 510301, China. .,Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, China.
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Ücker M, Ansorge R, Sato Y, Sayavedra L, Breusing C, Dubilier N. Deep-sea mussels from a hybrid zone on the Mid-Atlantic Ridge host genetically indistinguishable symbionts. THE ISME JOURNAL 2021; 15:3076-3083. [PMID: 33972724 PMCID: PMC8443746 DOI: 10.1038/s41396-021-00927-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 01/26/2021] [Accepted: 02/03/2021] [Indexed: 02/04/2023]
Abstract
The composition and diversity of animal microbiomes is shaped by a variety of factors, many of them interacting, such as host traits, the environment, and biogeography. Hybrid zones, in which the ranges of two host species meet and hybrids are found, provide natural experiments for determining the drivers of microbiome communities, but have not been well studied in marine environments. Here, we analysed the composition of the symbiont community in two deep-sea, Bathymodiolus mussel species along their known distribution range at hydrothermal vents on the Mid-Atlantic Ridge, with a focus on the hybrid zone where they interbreed. In-depth metagenomic analyses of the sulphur-oxidising symbionts of 30 mussels from the hybrid zone, at a resolution of single nucleotide polymorphism analyses of ~2500 orthologous genes, revealed that parental and hybrid mussels (F2-F4 generation) have genetically indistinguishable symbionts. While host genetics does not appear to affect symbiont composition in these mussels, redundancy analyses showed that geographic location of the mussels on the Mid-Atlantic Ridge explained most of the symbiont genetic variability compared to the other factors. We hypothesise that geographic structuring of the free-living symbiont population plays a major role in driving the composition of the microbiome in these deep-sea mussels.
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Affiliation(s)
- Merle Ücker
- grid.419529.20000 0004 0491 3210Max Planck Institute for Marine Microbiology, Bremen, Germany ,grid.7704.40000 0001 2297 4381MARUM—Center for Marine Environmental Sciences of the University of Bremen, Bremen, Germany
| | - Rebecca Ansorge
- grid.419529.20000 0004 0491 3210Max Planck Institute for Marine Microbiology, Bremen, Germany ,grid.40368.390000 0000 9347 0159Quadram Institute Bioscience, Norwich, Norfolk UK
| | - Yui Sato
- grid.419529.20000 0004 0491 3210Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Lizbeth Sayavedra
- grid.419529.20000 0004 0491 3210Max Planck Institute for Marine Microbiology, Bremen, Germany ,grid.40368.390000 0000 9347 0159Quadram Institute Bioscience, Norwich, Norfolk UK
| | - Corinna Breusing
- grid.20431.340000 0004 0416 2242University of Rhode Island, Graduate School of Oceanography, Narragansett, RI USA
| | - Nicole Dubilier
- grid.419529.20000 0004 0491 3210Max Planck Institute for Marine Microbiology, Bremen, Germany ,grid.7704.40000 0001 2297 4381MARUM—Center for Marine Environmental Sciences of the University of Bremen, Bremen, Germany
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5
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Zhang K, Sun J, Xu T, Qiu JW, Qian PY. Phylogenetic Relationships and Adaptation in Deep-Sea Mussels: Insights from Mitochondrial Genomes. Int J Mol Sci 2021; 22:ijms22041900. [PMID: 33672964 PMCID: PMC7918742 DOI: 10.3390/ijms22041900] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 01/31/2021] [Accepted: 02/08/2021] [Indexed: 11/16/2022] Open
Abstract
Mitochondrial genomes (mitogenomes) are an excellent source of information for phylogenetic and evolutionary studies, but their application in marine invertebrates is limited. In the present study, we utilized mitogenomes to elucidate the phylogeny and environmental adaptation in deep-sea mussels (Mytilidae: Bathymodiolinae). We sequenced and assembled seven bathymodioline mitogenomes. A phylogenetic analysis integrating the seven newly assembled and six previously reported bathymodioline mitogenomes revealed that these bathymodiolines are divided into three well-supported clades represented by five Gigantidas species, six Bathymodiolus species, and two "Bathymodiolus" species, respectively. A Common interval Rearrangement Explorer (CREx) analysis revealed a gene order rearrangement in bathymodiolines that is distinct from that in other shallow-water mytilids. The CREx analysis also suggested that reversal, transposition, and tandem duplications with subsequent random gene loss (TDRL) may have been responsible for the evolution of mitochondrial gene orders in bathymodiolines. Moreover, a comparison of the mitogenomes of shallow-water and deep-sea mussels revealed that the latter lineage has experienced relaxed purifying selection, but 16 residues of the atp6, nad4, nad2, cob, nad5, and cox2 genes have underwent positive selection. Overall, this study provides new insights into the phylogenetic relationships and mitogenomic adaptations of deep-sea mussels.
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Affiliation(s)
- Kai Zhang
- Department of Ocean Science, Hong Kong Branch of the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong 93117, China; (K.Z.); (J.S.); (T.X.)
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510225, China
| | - Jin Sun
- Department of Ocean Science, Hong Kong Branch of the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong 93117, China; (K.Z.); (J.S.); (T.X.)
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510225, China
| | - Ting Xu
- Department of Ocean Science, Hong Kong Branch of the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong 93117, China; (K.Z.); (J.S.); (T.X.)
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510225, China
- Department of Biology, Hong Kong Baptist University, Hong Kong 93117, China
| | - Jian-Wen Qiu
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510225, China
- Department of Biology, Hong Kong Baptist University, Hong Kong 93117, China
- Correspondence: (J.-W.Q.); (P.-Y.Q.)
| | - Pei-Yuan Qian
- Department of Ocean Science, Hong Kong Branch of the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong 93117, China; (K.Z.); (J.S.); (T.X.)
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 510225, China
- Correspondence: (J.-W.Q.); (P.-Y.Q.)
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Breusing C, Franke M, Young CR. Intra-host symbiont diversity in eastern Pacific cold seep tubeworms identified by the 16S-V6 region, but undetected by the 16S-V4 region. PLoS One 2020; 15:e0227053. [PMID: 31940381 PMCID: PMC6961877 DOI: 10.1371/journal.pone.0227053] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 12/11/2019] [Indexed: 11/18/2022] Open
Abstract
Vestimentiferan tubeworms are key taxa in deep-sea chemosynthetic habitats worldwide. As adults they obtain their nutrition through their sulfide-oxidizing bacterial endosymbionts, which are acquired from the environment. Although horizontal transmission should favor infections by various symbiotic microbes, the current paradigm holds that every tubeworm harbors only one endosymbiotic 16S rRNA phylotype. Although previous studies based on traditional Sanger sequencing have questioned these findings, population level high-throughput analyses of the symbiont 16S diversity are still missing. To get further insights into the symbiont genetic variation and uncover hitherto hidden diversity we applied state-of-the-art 16S-V4 amplicon sequencing to populations of the co-occurring tubeworm species Lamellibrachia barhami and Escarpia spicata that were collected during E/V Nautilus and R/V Western Flyer cruises to cold seeps in the eastern Pacific Ocean. In agreement with earlier work our sequence data indicated that L. barhami and E. spicata share one monomorphic symbiont phylotype. However, complementary CARD-FISH analyses targeting the 16S-V6 region implied the existence of an additional phylotype in L. barhami. Our results suggest that the V4 region might not be sufficiently variable to investigate diversity in the intra-host symbiont population at least in the analyzed sample set. This is an important finding given that this region has become the standard molecular marker for high-throughput microbiome analyses. Further metagenomic research will be necessary to solve these issues and to uncover symbiont diversity that is hidden below the 16S rRNA level.
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Affiliation(s)
- Corinna Breusing
- Monterey Bay Aquarium Research Institute, Moss Landing, CA, United States of America
- National Oceanography Centre, Southampton, England, United Kingdom
- * E-mail:
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Plouviez S, LaBella AL, Weisrock DW, von Meijenfeldt FAB, Ball B, Neigel JE, Van Dover CL. Amplicon sequencing of 42 nuclear loci supports directional gene flow between South Pacific populations of a hydrothermal vent limpet. Ecol Evol 2019; 9:6568-6580. [PMID: 31312428 PMCID: PMC6609911 DOI: 10.1002/ece3.5235] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 04/16/2019] [Accepted: 04/17/2019] [Indexed: 12/05/2022] Open
Abstract
In the past few decades, population genetics and phylogeographic studies have improved our knowledge of connectivity and population demography in marine environments. Studies of deep-sea hydrothermal vent populations have identified barriers to gene flow, hybrid zones, and demographic events, such as historical population expansions and contractions. These deep-sea studies, however, used few loci, which limit the amount of information they provided for coalescent analysis and thus our ability to confidently test complex population dynamics scenarios. In this study, we investigated population structure, demographic history, and gene flow directionality among four Western Pacific hydrothermal vent populations of the vent limpet Lepetodrilus aff. schrolli. These vent sites are located in the Manus and Lau back-arc basins, currently of great interest for deep-sea mineral extraction. A total of 42 loci were sequenced from each individual using high-throughput amplicon sequencing. Amplicon sequences were analyzed using both genetic variant clustering methods and evolutionary coalescent approaches. Like most previously investigated vent species in the South Pacific, L. aff. schrolli showed no genetic structure within basins but significant differentiation between basins. We inferred significant directional gene flow from Manus Basin to Lau Basin, with low to no gene flow in the opposite direction. This study is one of the very few marine population studies using >10 loci for coalescent analysis and serves as a guide for future marine population studies.
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Affiliation(s)
- Sophie Plouviez
- Department of BiologyUniversity of Louisiana at LafayetteLafayetteLouisiana
- Division of Marine Science and Conservation, Nicholas School of the EnvironmentDuke UniversityBeaufortNorth Carolina
| | | | | | | | - Bernard Ball
- School of Biological, Earth & Environmental SciencesUniversity College CorkCorkIreland
| | - Joseph E. Neigel
- Department of BiologyUniversity of Louisiana at LafayetteLafayetteLouisiana
| | - Cindy L. Van Dover
- Division of Marine Science and Conservation, Nicholas School of the EnvironmentDuke UniversityBeaufortNorth Carolina
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Roterman CN, Lee WK, Liu X, Lin R, Li X, Won YJ. A new yeti crab phylogeny: Vent origins with indications of regional extinction in the East Pacific. PLoS One 2018; 13:e0194696. [PMID: 29547631 PMCID: PMC5856415 DOI: 10.1371/journal.pone.0194696] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 03/07/2018] [Indexed: 11/19/2022] Open
Abstract
The recent discovery of two new species of kiwaid squat lobsters on hydrothermal vents in the Pacific Ocean and in the Pacific sector of the Southern Ocean has prompted a re-analysis of Kiwaid biogeographical history. Using a larger alignment with more fossil calibrated nodes than previously, we consider the precise relationship between Kiwaidae, Chirostylidae and Eumunididae within Chirostyloidea (Decapoda: Anomura) to be still unresolved at present. Additionally, the placement of both new species within a new “Bristly” clade along with the seep-associated Kiwa puravida is most parsimoniously interpreted as supporting a vent origin for the family, rather than a seep-to-vent progression. Fossil-calibrated divergence analysis indicates an origin for the clade around the Eocene-Oligocene boundary in the eastern Pacific ~33–38 Ma, coincident with a lowering of bottom temperatures and increased ventilation in the Pacific deep sea. Likewise, the mid-Miocene (~10–16 Ma) rapid radiation of the new Bristly clade also coincides with a similar cooling event in the tropical East Pacific. The distribution, diversity, tree topology and divergence timing of Kiwaidae in the East Pacific is most consistent with a pattern of extinctions, recolonisations and radiations along fast-spreading ridges in this region and may have been punctuated by large-scale fluctuations in deep-water ventilation and temperature during the Cenozoic; further affecting the viability of Kiwaidae populations along portions of mid-ocean ridge.
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Affiliation(s)
| | - Won-Kyung Lee
- Department of Life Science, Division of EcoScience, Ewha Womans University, Seoul, Republic of Korea
- Deep-sea and Seabed Mineral Resources Research Center, Korea Institute of Ocean Science & Technology, Ansan, Republic of Korea
| | - Xinming Liu
- Guangxi Academy of Oceanography, Nanning, China
- Institute of Oceanology, Chinese Academy of Science, Qingdao, China
| | - Rongcheng Lin
- Third Institute of Oceanography, State Oceanic Administration, Xiamen, China
| | - Xinzheng Li
- Institute of Oceanology, Chinese Academy of Science, Qingdao, China
- University of Chinese Academy of Sciences, Beijing, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Yong-Jin Won
- Department of Life Science, Division of EcoScience, Ewha Womans University, Seoul, Republic of Korea
- * E-mail:
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Dai C, Hao Y, He Y, Lei F. The absence of reproductive isolation between non-sister and deeply diverged mitochondrial lineages of the black-throated tit (Aegithalos concinnus) revealed by a multilocus genetic analysis in a contact zone. BMC Evol Biol 2017; 17:266. [PMID: 29262786 PMCID: PMC5738821 DOI: 10.1186/s12862-017-1114-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2017] [Accepted: 12/11/2017] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND A deep divergence of mitochondrial DNA is common in species delimitated by morphological traits. Several hypotheses can explain such variations, such as cryptic species, introgression, allopatric divergence and ancestral lineage. The black-throated tit harbors several deeply divergent mitochondrial lineages. Two lineages with 5% divergence, but having a high level of gene flow, have been detected in its subspecies, A. C. concinnus and A. c. talifuenses. In this study, we conducted a genetic analysis at a contact zone of these two lineages to identify whether these lineages either reflect a high level of intraspecific variation in mitochondrial loci or represent incipient speciation. Mitochondrial ND2 and 11 microsatellite loci were used to conduct phylogenetic and population structure analyses. RESULTS ND2 haplotypes actually diverged into two groups within subspecies A. c. talifuenses; however, they formed a non-sister relationship when including all available GenBank ND2 sequences. Analyses of microsatellite data indicated no existing population structure and showed a pattern of isolation by distance. Individuals sampled at the contact zone were almost identified as F2 hybrids. CONCLUSIONS Isolation for 2.4 Ma, as suggested by a previous study, appeared to be insufficient to develop robust reproductive barriers. Reproductive barriers were weak, or even absent between the divergent lineages, highlighting that incipient speciation was unlikely to be the case. Considering the results from previous studies, the divergent lineages may be better explained by secondary contact after allopatric isolation because of Pleistocene climate changes, but other hypotheses cannot be definitively ruled out because of the lack of representative samples from the other distribution region and its relatives. Considering that divergence in morphology was hardly observed and the particular split in genetics, the two subspecies might be better merged. The current findings also highlight the likely contribution of male-biased dispersal to male-biased gene flow among mitochondrial lineages; more efforts are needed to illustrate the evolutionary history of the black-throated tit.
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Affiliation(s)
- Chuanyin Dai
- School of Chemistry and Life Sciences, Guizhou Normal College, Gaoxin Road 115, Guiyang, Guizhou 550018 China
| | - Yan Hao
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beichen Xi Road 1, Beijing, 100101 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Yong He
- School of Chemistry and Life Sciences, Guizhou Normal College, Gaoxin Road 115, Guiyang, Guizhou 550018 China
| | - Fumin Lei
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beichen Xi Road 1, Beijing, 100101 China
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Zheng P, Wang M, Li C, Sun X, Wang X, Sun Y, Sun S. Insights into deep-sea adaptations and host-symbiont interactions: A comparative transcriptome study on Bathymodiolus
mussels and their coastal relatives. Mol Ecol 2017; 26:5133-5148. [DOI: 10.1111/mec.14160] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Revised: 04/12/2017] [Accepted: 04/14/2017] [Indexed: 01/09/2023]
Affiliation(s)
- Ping Zheng
- Key Laboratory of Marine Ecology and Environmental Sciences; Institute of Oceanology; Chinese Academy of Sciences; Qingdao China
- University of Chinese Academy of Sciences; Beijing China
| | - Minxiao Wang
- Key Laboratory of Marine Ecology and Environmental Sciences; Institute of Oceanology; Chinese Academy of Sciences; Qingdao China
- Deep Sea Research Center; Institute of Oceanology; Chinese Academy of Sciences; Qingdao China
| | - Chaolun Li
- Key Laboratory of Marine Ecology and Environmental Sciences; Institute of Oceanology; Chinese Academy of Sciences; Qingdao China
- University of Chinese Academy of Sciences; Beijing China
- Deep Sea Research Center; Institute of Oceanology; Chinese Academy of Sciences; Qingdao China
- Laboratory for Marine Ecology and Environmental Science; Qingdao National Laboratory for Marine Science and Technology; Qingdao China
| | | | - Xiaocheng Wang
- Key Laboratory of Marine Ecology and Environmental Sciences; Institute of Oceanology; Chinese Academy of Sciences; Qingdao China
- University of Chinese Academy of Sciences; Beijing China
| | - Yan Sun
- Key Laboratory of Marine Ecology and Environmental Sciences; Institute of Oceanology; Chinese Academy of Sciences; Qingdao China
| | - Song Sun
- Key Laboratory of Marine Ecology and Environmental Sciences; Institute of Oceanology; Chinese Academy of Sciences; Qingdao China
- University of Chinese Academy of Sciences; Beijing China
- Laboratory for Marine Ecology and Environmental Science; Qingdao National Laboratory for Marine Science and Technology; Qingdao China
- Jiaozhou Bay Marine Ecosystem Research Station; Chinese Academy of Sciences; Qingdao China
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11
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Taylor ML, Roterman CN. Invertebrate population genetics across Earth's largest habitat: The deep-sea floor. Mol Ecol 2017; 26:4872-4896. [PMID: 28833857 DOI: 10.1111/mec.14237] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 06/16/2017] [Accepted: 06/19/2017] [Indexed: 01/04/2023]
Abstract
Despite the deep sea being the largest habitat on Earth, there are just 77 population genetic studies of invertebrates (115 species) inhabiting non-chemosynthetic ecosystems on the deep-sea floor (below 200 m depth). We review and synthesize the results of these papers. Studies reveal levels of genetic diversity comparable to shallow-water species. Generally, populations at similar depths were well connected over 100s-1,000s km, but studies that sampled across depth ranges reveal population structure at much smaller scales (100s-1,000s m) consistent with isolation by adaptation across environmental gradients, or the existence of physical barriers to connectivity with depth. Few studies were ocean-wide (under 4%), and 48% were Atlantic-focused. There is strong emphasis on megafauna and commercial species with research into meiofauna, "ecosystem engineers" and other ecologically important species lacking. Only nine papers account for ~50% of the planet's surface (depths below 3,500 m). Just two species were studied below 5,000 m, a quarter of Earth's seafloor. Most studies used single-locus mitochondrial genes revealing a common pattern of non-neutrality, consistent with demographic instability or selective sweeps; similar to deep-sea hydrothermal vent fauna. The absence of a clear difference between vent and non-vent could signify that demographic instability is common in the deep sea, or that selective sweeps render single-locus mitochondrial studies demographically uninformative. The number of population genetics studies to date is miniscule in relation to the size of the deep sea. The paucity of studies constrains meta-analyses where broad inferences about deep-sea ecology could be made.
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Affiliation(s)
- M L Taylor
- Department of Zoology, University of Oxford, Oxford, UK
| | - C N Roterman
- Department of Zoology, University of Oxford, Oxford, UK
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Ho PT, Park E, Hong SG, Kim EH, Kim K, Jang SJ, Vrijenhoek RC, Won YJ. Geographical structure of endosymbiotic bacteria hosted by Bathymodiolus mussels at eastern Pacific hydrothermal vents. BMC Evol Biol 2017; 17:121. [PMID: 28558648 PMCID: PMC5450337 DOI: 10.1186/s12862-017-0966-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 05/12/2017] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Chemolithoautotrophic primary production sustains dense invertebrate communities at deep-sea hydrothermal vents and hydrocarbon seeps. Symbiotic bacteria that oxidize dissolved sulfur, methane, and hydrogen gases nourish bathymodiolin mussels that thrive in these environments worldwide. The mussel symbionts are newly acquired in each generation via infection by free-living forms. This study examined geographical subdivision of the thiotrophic endosymbionts hosted by Bathymodiolus mussels living along the eastern Pacific hydrothermal vents. High-throughput sequencing data of 16S ribosomal RNA encoding gene and fragments of six protein-coding genes of symbionts were examined in the samples collected from nine vent localities at the East Pacific Rise, Galápagos Rift, and Pacific-Antarctic Ridge. RESULTS Both of the parapatric sister-species, B. thermophilus and B. antarcticus, hosted the same numerically dominant phylotype of thiotrophic Gammaproteobacteria. However, sequences from six protein-coding genes revealed highly divergent symbiont lineages living north and south of the Easter Microplate and hosted by these two Bathymodiolus mussel species. High heterogeneity of symbiont haplotypes among host individuals sampled from the same location suggested that stochasticity associated with initial infections was amplified as symbionts proliferated within the host individuals. The mussel species presently contact one another and hybridize along the Easter Microplate, but the northern and southern symbionts appear to be completely isolated. Vicariance associated with orogeny of the Easter Microplate region, 2.5-5.3 million years ago, may have initiated isolation of the symbiont and host populations. Estimates of synonymous substitution rates for the protein-coding bacterial genes examined in this study were 0.77-1.62%/nucleotide/million years. CONCLUSIONS Our present study reports the most comprehensive population genetic analyses of the chemosynthetic endosymbiotic bacteria based on high-throughput genetic data and extensive geographical sampling to date, and demonstrates the role of the geographical features, the Easter Microplate and geographical distance, in the intraspecific divergence of this bacterial species along the mid-ocean ridge axes in the eastern Pacific. Altogether, our results provide insights into extrinsic and intrinsic factors affecting the dispersal and evolution of chemosynthetic symbiotic partners in the hydrothermal vents along the eastern Pacific Ocean.
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Affiliation(s)
- Phuong-Thao Ho
- Interdisciplinary Program of EcoCreative, The Graduate School, Ewha Womans University, Seoul, 03760, Korea
| | - Eunji Park
- Division of EcoScience, Ewha Womans University, Seoul, 03760, Korea
| | - Soon Gyu Hong
- Division of Polar Life Sciences, Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, Incheon, 21990, Republic of Korea
| | - Eun-Hye Kim
- Division of Polar Life Sciences, Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, Incheon, 21990, Republic of Korea
| | - Kangchon Kim
- Interdisciplinary Program of EcoCreative, The Graduate School, Ewha Womans University, Seoul, 03760, Korea
| | - Sook-Jin Jang
- Interdisciplinary Program of EcoCreative, The Graduate School, Ewha Womans University, Seoul, 03760, Korea
| | | | - Yong-Jin Won
- Interdisciplinary Program of EcoCreative, The Graduate School, Ewha Womans University, Seoul, 03760, Korea. .,Division of EcoScience, Ewha Womans University, Seoul, 03760, Korea.
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Sun J, Zhang Y, Xu T, Zhang Y, Mu H, Zhang Y, Lan Y, Fields CJ, Hui JHL, Zhang W, Li R, Nong W, Cheung FKM, Qiu JW, Qian PY. Adaptation to deep-sea chemosynthetic environments as revealed by mussel genomes. Nat Ecol Evol 2017; 1:121. [PMID: 28812709 DOI: 10.1038/s41559-017-0121] [Citation(s) in RCA: 171] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 02/16/2017] [Indexed: 01/08/2023]
Abstract
Hydrothermal vents and methane seeps are extreme deep-sea ecosystems that support dense populations of specialized macro-benthos such as mussels. But the lack of genome information hinders the understanding of the adaptation of these animals to such inhospitable environments. Here we report the genomes of a deep-sea vent/seep mussel (Bathymodiolus platifrons) and a shallow-water mussel (Modiolus philippinarum). Phylogenetic analysis shows that these mussel species diverged approximately 110.4 million years ago. Many gene families, especially those for stabilizing protein structures and removing toxic substances from cells, are highly expanded in B. platifrons, indicating adaptation to extreme environmental conditions. The innate immune system of B. platifrons is considerably more complex than that of other lophotrochozoan species, including M. philippinarum, with substantial expansion and high expression levels of gene families that are related to immune recognition, endocytosis and caspase-mediated apoptosis in the gill, revealing presumed genetic adaptation of the deep-sea mussel to the presence of its chemoautotrophic endosymbionts. A follow-up metaproteomic analysis of the gill of B. platifrons shows methanotrophy, assimilatory sulfate reduction and ammonia metabolic pathways in the symbionts, providing energy and nutrients, which allow the host to thrive. Our study of the genomic composition allowing symbiosis in extremophile molluscs gives wider insights into the mechanisms of symbiosis in other organisms such as deep-sea tubeworms and giant clams.
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Affiliation(s)
- Jin Sun
- Division of Life Science, Hong Kong University of Science and Technology, Hong Kong, China.,Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Yu Zhang
- Shenzhen Key Laboratory of Marine Bioresource and Eco-Environmental Science, College of Life Science, Shenzhen University, Shenzhen, China
| | - Ting Xu
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Yang Zhang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
| | - Huawei Mu
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Yanjie Zhang
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Yi Lan
- Division of Life Science, Hong Kong University of Science and Technology, Hong Kong, China
| | - Christopher J Fields
- High Performance Computing in Biology, Roy J. Carver Biotechnology Centre, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Jerome Ho Lam Hui
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences, Centre for Soybean Research, Partner State Key Laboratory of Agrobiotechnology, the Chinese University of Hong Kong, Hong Kong, China
| | - Weipeng Zhang
- Division of Life Science, Hong Kong University of Science and Technology, Hong Kong, China
| | - Runsheng Li
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Wenyan Nong
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences, Centre for Soybean Research, Partner State Key Laboratory of Agrobiotechnology, the Chinese University of Hong Kong, Hong Kong, China
| | - Fiona Ka Man Cheung
- Simon F. S. Li Marine Science Laboratory, School of Life Sciences, Centre for Soybean Research, Partner State Key Laboratory of Agrobiotechnology, the Chinese University of Hong Kong, Hong Kong, China
| | - Jian-Wen Qiu
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Pei-Yuan Qian
- Division of Life Science, Hong Kong University of Science and Technology, Hong Kong, China.,HKUST-CAS Joint Laboratory, Sanya Institute of Deep Sea Science and Engineering, Sanya 572000, China
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14
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Breusing C, Vrijenhoek RC, Reusch TBH. Widespread introgression in deep-sea hydrothermal vent mussels. BMC Evol Biol 2017; 17:13. [PMID: 28086786 PMCID: PMC5237248 DOI: 10.1186/s12862-016-0862-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 12/21/2016] [Indexed: 11/29/2022] Open
Abstract
Background The analysis of hybrid zones is crucial for gaining a mechanistic understanding of the process of speciation and the maintenance of species boundaries. Hybrid zones have been studied intensively in terrestrial and shallow-water ecosystems, but very little is known about their occurrence in deep-sea environments. Here we used diagnostic, single nucleotide polymorphisms in combination with one mitochondrial gene to re-examine prior hypotheses about a contact zone involving deep-sea hydrothermal vent mussels, Bathymodiolus azoricus and B. puteoserpentis, living along the Mid-Atlantic Ridge. Results Admixture was found to be asymmetric with respect to the parental species, while introgression was more widespread geographically than previously recognized. Admixed individuals with a majority of alleles from one of the parental species were most frequent in habitats corresponding to that species. Mussels found at a geographically intermediate vent field constituted a genetically mixed population that showed no evidence for hybrid incompatibilities, a finding that does not support a previously inferred tension zone model. Conclusions Our analyses indicate that B. azoricus and B. puteoserpentis hybridize introgressively across a large geographic area without evidence for general hybrid incompatibilities. While these findings shed new light onto the genetic structure of this hybrid zone, many aspects about its nature still remain obscure. Our study sets a baseline for further research that should primarily focus on the acquisition of additional mussel samples and environmental data, a detailed exploration of vent areas and hidden populations as well as genomic analyses in both mussel hosts and their bacterial symbionts. Electronic supplementary material The online version of this article (doi:10.1186/s12862-016-0862-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Corinna Breusing
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Evolutionary Ecology of Marine Fishes, Düsternbrooker Weg 20, 24105, Kiel, Germany. .,Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, CA, 95039, USA.
| | - Robert C Vrijenhoek
- Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, CA, 95039, USA
| | - Thorsten B H Reusch
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Evolutionary Ecology of Marine Fishes, Düsternbrooker Weg 20, 24105, Kiel, Germany
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15
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Jang SJ, Park E, Lee WK, Johnson SB, Vrijenhoek RC, Won YJ. Population subdivision of hydrothermal vent polychaete Alvinella pompejana across equatorial and Easter Microplate boundaries. BMC Evol Biol 2016; 16:235. [PMID: 27793079 PMCID: PMC5084463 DOI: 10.1186/s12862-016-0807-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 10/14/2016] [Indexed: 11/29/2022] Open
Abstract
Background The Equator and Easter Microplate regions of the eastern Pacific Ocean exhibit geomorphological and hydrological features that create barriers to dispersal for a number of animals associated with deep-sea hydrothermal vent habitats. This study examined effects of these boundaries on geographical subdivision of the vent polychaete Alvinella pompejana. DNA sequences from one mitochondrial and eleven nuclear genes were examined in samples collected from ten vent localities that comprise the species’ known range from 23°N latitude on the East Pacific Rise to 38°S latitude on the Pacific Antarctic Ridge. Results Multi-locus genotypes inferred from these sequences clustered the individual worms into three metapopulation segments — the northern East Pacific Rise (NEPR), southern East Pacific Rise (SEPR), and northeastern Pacific Antarctic Ridge (PAR) — separated by the Equator and Easter Microplate boundaries. Genetic diversity estimators were negatively correlated with tectonic spreading rates. Application of the isolation-with-migration (IMa2) model provided information about divergence times and demographic parameters. The PAR and NEPR metapopulation segments were estimated to have split roughly 4.20 million years ago (Mya) (2.42–33.42 Mya, 95 % highest posterior density, (HPD)), followed by splitting of the SEPR and NEPR segments about 0.79 Mya (0.07–6.67 Mya, 95 % HPD). Estimates of gene flow between the neighboring regions were mostly low (2 Nm < 1). Estimates of effective population size decreased with southern latitudes: NEPR > SEPR > PAR. Conclusions Highly effective dispersal capabilities allow A. pompejana to overcome the temporal instability and intermittent distribution of active hydrothermal vents in the eastern Pacific Ocean. Consequently, the species exhibits very high levels of genetic diversity compared with many co-distributed vent annelids and mollusks. Nonetheless, its levels of genetic diversity in partially isolated populations are inversely correlated with tectonic spreading rates. As for many other vent taxa, this pioneering colonizer is similarly affected by local rates of habitat turnover and by major dispersal filters associated with the Equator and the Easter Microplate region. Electronic supplementary material The online version of this article (doi:10.1186/s12862-016-0807-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sook-Jin Jang
- Interdisciplinary Program of EcoCreative, The Graduate School, Ewha Womans University, Seoul, South Korea
| | - Eunji Park
- Division of Ecoscience, Ewha Womans University, Seoul, South Korea
| | - Won-Kyung Lee
- Division of Ecoscience, Ewha Womans University, Seoul, South Korea
| | - Shannon B Johnson
- Monterey Bay Aquarium Research Institute, Moss Landing, CA, 95039-9644, USA
| | | | - Yong-Jin Won
- Interdisciplinary Program of EcoCreative, The Graduate School, Ewha Womans University, Seoul, South Korea. .,Division of Ecoscience, Ewha Womans University, Seoul, South Korea.
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16
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Breusing C, Johnson SB, Tunnicliffe V, Vrijenhoek RC. Population structure and connectivity in Indo-Pacific deep-sea mussels of the Bathymodiolus septemdierum complex. CONSERV GENET 2015. [DOI: 10.1007/s10592-015-0750-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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17
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Fontanez KM, Cavanaugh CM. Evidence for horizontal transmission from multilocus phylogeny of deep-sea mussel (Mytilidae) symbionts. Environ Microbiol 2014; 16:3608-21. [DOI: 10.1111/1462-2920.12379] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 12/22/2013] [Indexed: 11/29/2022]
Affiliation(s)
- Kristina M. Fontanez
- Department of Organismic and Evolutionary Biology; Harvard University; Cambridge MA 02138 USA
| | - Colleen M. Cavanaugh
- Department of Organismic and Evolutionary Biology; Harvard University; Cambridge MA 02138 USA
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18
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Plouviez S, Faure B, Le Guen D, Lallier FH, Bierne N, Jollivet D. A new barrier to dispersal trapped old genetic clines that escaped the Easter Microplate tension zone of the Pacific vent mussels. PLoS One 2013; 8:e81555. [PMID: 24312557 PMCID: PMC3846894 DOI: 10.1371/journal.pone.0081555] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 10/21/2013] [Indexed: 11/23/2022] Open
Abstract
Comparative phylogeography of deep-sea hydrothermal vent species has uncovered several genetic breaks between populations inhabiting northern and southern latitudes of the East Pacific Rise. However, the geographic width and position of genetic clines are variable among species. In this report, we further characterize the position and strength of barriers to gene flow between populations of the deep-sea vent mussel Bathymodiolus thermophilus. Eight allozyme loci and DNA sequences of four nuclear genes were added to previously published sequences of the cytochrome c oxidase subunit I gene. Our data confirm the presence of two barriers to gene flow, one located at the Easter Microplate (between 21°33′S and 31°S) recently described as a hybrid zone, and the second positioned between 7°25′S and 14°S with each affecting different loci. Coalescence analysis indicates a single vicariant event at the origin of divergence between clades for all nuclear loci, although the clines are now spatially discordant. We thus hypothesize that the Easter Microplate barrier has recently been relaxed after a long period of isolation and that some genetic clines have escaped the barrier and moved northward where they have subsequently been trapped by a reinforcing barrier to gene flow between 7°25′S and 14°S.
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Affiliation(s)
- Sophie Plouviez
- Université Pierre et Marie Curie-Paris 6, Laboratoire Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, Roscoff, France
- CNRS UMR 7144, Station Biologique de Roscoff, Roscoff, France
- Division of Marine Science and Conservation, Nicholas School of the Environment, Duke University, Beaufort, North Carolina, United States of America
- * E-mail:
| | - Baptiste Faure
- Université Pierre et Marie Curie-Paris 6, Laboratoire Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, Roscoff, France
- CNRS UMR 7144, Station Biologique de Roscoff, Roscoff, France
- Université Montpellier 2, Montpellier, France
- CNRS UMR 5554, Institut des Sciences de l’Evolution, Station Méditerranéenne de l’Environnement Littoral, Sète, France
| | - Dominique Le Guen
- Université Pierre et Marie Curie-Paris 6, Laboratoire Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, Roscoff, France
- CNRS UMR 7144, Station Biologique de Roscoff, Roscoff, France
| | - François H. Lallier
- Université Pierre et Marie Curie-Paris 6, Laboratoire Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, Roscoff, France
- CNRS UMR 7144, Station Biologique de Roscoff, Roscoff, France
| | - Nicolas Bierne
- Université Montpellier 2, Montpellier, France
- CNRS UMR 5554, Institut des Sciences de l’Evolution, Station Méditerranéenne de l’Environnement Littoral, Sète, France
| | - Didier Jollivet
- Université Pierre et Marie Curie-Paris 6, Laboratoire Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff, Roscoff, France
- CNRS UMR 7144, Station Biologique de Roscoff, Roscoff, France
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Thubaut J, Corbari L, Gros O, Duperron S, Couloux A, Samadi S. Integrative biology of Idas iwaotakii (Habe, 1958), a 'model species' associated with sunken organic substrates. PLoS One 2013; 8:e69680. [PMID: 23894520 PMCID: PMC3722101 DOI: 10.1371/journal.pone.0069680] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Accepted: 06/11/2013] [Indexed: 11/19/2022] Open
Abstract
The giant bathymodioline mussels from vents have been studied as models to understand the adaptation of organisms to deep-sea chemosynthetic environments. These mussels are closely related to minute mussels associated to organic remains decaying on the deep-sea floor. Whereas biological data accumulate for the giant mussels, the small mussels remain poorly studied. Despite this lack of data for species living on organic remains it has been hypothesized that during evolution, contrary to their relatives from vents or seeps, they did not acquire highly specialized biological features. We aim at testing this hypothesis by providing new biological data for species associated with organic falls. Within Bathymodiolinae a close phylogenetic relationship was revealed between the Bathymodiolus sensu stricto lineage (i.e. “thermophilus” lineage) which includes exclusively vent and seep species, and a diversified lineage of small mussels, attributed to the genus Idas, that includes mostly species from organic falls. We selected Idas iwaotakii (Habe, 1958) from this latter lineage to analyse population structure and to document biological features. Mitochondrial and nuclear markers reveal a north-south genetic structure at an oceanic scale in the Western Pacific but no structure was revealed at a regional scale or as correlated with the kind of substrate or depth. The morphology of larval shells suggests substantial dispersal abilities. Nutritional features were assessed by examining bacterial diversity coupled by a microscopic analysis of the digestive tract. Molecular data demonstrated the presence of sulphur-oxidizing bacteria resembling those identified in other Bathymodiolinae. In contrast with most Bathymodiolus s.s. species the digestive tract of I. iwaotakii is not reduced. Combining data from literature with the present data shows that most of the important biological features are shared between Bathymodiolus s.s. species and its sister-lineage. However Bathymodiolus s.s. species are ecologically more restricted and also display a lower species richness than Idas species.
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Affiliation(s)
- Justine Thubaut
- Département Systématique et Evolution, UMR 7138 UPMC-IRD-MNHN-CNRS, Muséum national d'Histoire naturelle, Paris, France.
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