1
|
Zheng S, Zhang C, Zhou J, Zhang S, Liu Y, Jin X, Wang Y, Liu B. Daphnia sp. (Branchiopoda: Cladocera) Mitochondrial Genome Gene Rearrangement and Phylogenetic Position Within Branchiopoda. Biochem Genet 2024; 62:3030-3051. [PMID: 38063953 DOI: 10.1007/s10528-023-10594-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 11/08/2023] [Indexed: 07/31/2024]
Abstract
In high-altitude (4500 m) freshwater lakes, Daphnia is the apex species and the dominant zooplankton. It frequently dwells in the same lake as the Gammarid. Branchiopoda, a class of Arthropoda, Crustacea, is a relatively primitive group in the subphylum Crustacea, which originated in the Cambrian period of the Paleozoic. The complete mitogenome sequence of Daphnia sp. (Branchiopoda: Cladocera) was sequenced and annotated in this study and deposited in GenBank. The sequence structure of this species was studied by comparing the original sequences with BLAST. In addition, we have also researched the mechanisms of their mitochondrial gene rearrangement by establishing a model. We have used the Bayesian inference [BI] and maximum likelihood [ML] methods to proceed with phylogenetic analysis inference, which generates identical phylogenetic topology that reveals the phylogenetic state of Daphnia. The complete mitogenome of Daphnia sp. shows that it was 15,254 bp in length and included two control regions (CRs) and 37 genes (13 protein-coding genes, 22 tRNAs and two ribosomal RNAs [16S and 12S]). In addition to tRNA-Ser (GCT), other tRNAs have a typical cloverleaf secondary structure. Meanwhile, the mitogenome of Daphnia sp. was clearly rearranged when compared to the mitogenome of typical Daphnia. In a word, we report a newly sequenced mitogenome of Daphnia sp. with a unique rearrangement phenomenon. These results will be helpful for further phylogenetic research and provide a foundation for future studies on the characteristics of the mitochondrial gene arrangement process in Daphnia.
Collapse
Affiliation(s)
- Sixu Zheng
- National Engineering Laboratory of Marine Germplasm Resources Exploration and Utilization, Zhejiang Ocean University, No.1, Haida South Road, Zhoushan, 316022, Zhejiang, People's Republic of China
| | - Chi Zhang
- Institute of Fisheries Science, Tibet Academy of Agricultural and Animal Husbandry Sciences, Lhasa, People's Republic of China.
| | - Jianshe Zhou
- Institute of Fisheries Science, Tibet Academy of Agricultural and Animal Husbandry Sciences, Lhasa, People's Republic of China
| | - Shufei Zhang
- Guangdong Provincial Key Laboratory of Fishery Ecology and Environment, South China Sea Fisheries Research Institute, Chinese Academy of Fisheries Sciences, Guangzhou, 510300, Guangdong, China
| | - Yifan Liu
- National Engineering Laboratory of Marine Germplasm Resources Exploration and Utilization, Zhejiang Ocean University, No.1, Haida South Road, Zhoushan, 316022, Zhejiang, People's Republic of China
| | - Xun Jin
- National Engineering Laboratory of Marine Germplasm Resources Exploration and Utilization, Zhejiang Ocean University, No.1, Haida South Road, Zhoushan, 316022, Zhejiang, People's Republic of China
| | - Yunpeng Wang
- National Engineering Laboratory of Marine Germplasm Resources Exploration and Utilization, Zhejiang Ocean University, No.1, Haida South Road, Zhoushan, 316022, Zhejiang, People's Republic of China
| | - Bingjian Liu
- National Engineering Laboratory of Marine Germplasm Resources Exploration and Utilization, Zhejiang Ocean University, No.1, Haida South Road, Zhoushan, 316022, Zhejiang, People's Republic of China.
| |
Collapse
|
2
|
Davison A, Chowdhury M, Johansen M, Uliano-Silva M, Blaxter M. High heteroplasmy is associated with low mitochondrial copy number and selection against non-synonymous mutations in the snail Cepaea nemoralis. BMC Genomics 2024; 25:596. [PMID: 38872121 DOI: 10.1186/s12864-024-10505-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Accepted: 06/06/2024] [Indexed: 06/15/2024] Open
Abstract
Molluscan mitochondrial genomes are unusual because they show wide variation in size, radical genome rearrangements and frequently show high variation (> 10%) within species. As progress in understanding this variation has been limited, we used whole genome sequencing of a six-generation matriline of the terrestrial snail Cepaea nemoralis, as well as whole genome sequences from wild-collected C. nemoralis, the sister species C. hortensis, and multiple other snail species to explore the origins of mitochondrial DNA (mtDNA) variation. The main finding is that a high rate of SNP heteroplasmy in somatic tissue was negatively correlated with mtDNA copy number in both Cepaea species. In individuals with under ten mtDNA copies per nuclear genome, more than 10% of all positions were heteroplasmic, with evidence for transmission of this heteroplasmy through the germline. Further analyses showed evidence for purifying selection acting on non-synonymous mutations, even at low frequency of the rare allele, especially in cytochrome oxidase subunit 1 and cytochrome b. The mtDNA of some individuals of Cepaea nemoralis contained a length heteroplasmy, including up to 12 direct repeat copies of tRNA-Val, with 24 copies in another snail, Candidula rugosiuscula, and repeats of tRNA-Thr in C. hortensis. These repeats likely arise due to error prone replication but are not correlated with mitochondrial copy number in C. nemoralis. Overall, the findings provide key insights into mechanisms of replication, mutation and evolution in molluscan mtDNA, and so will inform wider studies on the biology and evolution of mtDNA across animal phyla.
Collapse
Affiliation(s)
- Angus Davison
- School of Life Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
| | - Mehrab Chowdhury
- School of Life Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Margrethe Johansen
- School of Life Sciences, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Marcela Uliano-Silva
- Tree of Life, Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, Cambridgeshire, CB10 1SA, UK
| | - Mark Blaxter
- Tree of Life, Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, Cambridgeshire, CB10 1SA, UK
| |
Collapse
|
3
|
Murray CS, Karram M, Bass DJ, Doceti M, Becker D, Nunez JCB, Ratan A, Bergland AO. Balancing selection and the functional effects of shared polymorphism in cryptic Daphnia species. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.16.589693. [PMID: 38659826 PMCID: PMC11042267 DOI: 10.1101/2024.04.16.589693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
The patterns of genetic variation within and between related taxa represent the genetic history of a species. Shared polymorphisms, loci with identical alleles across species, are of unique interest as they may represent cases of ancient selection maintaining functional variation post-speciation. In this study, we investigate the abundance of shared polymorphism in the Daphnia pulex species complex. We test whether shared mutations are consistent with the action of balancing selection or alternative hypotheses such as hybridization, incomplete lineage sorting, or convergent evolution. We analyzed over 2,000 genomes from North American and European D. pulex and several outgroup species to examine the prevalence and distribution of shared alleles between the focal species pair, North American and European D. pulex. We show that while North American and European D. pulex diverged over ten million years ago, they retained tens of thousands of shared alleles. We found that the number of shared polymorphisms between North American and European D. pulex cannot be explained by hybridization or incomplete lineage sorting alone. Instead, we show that most shared polymorphisms could be the product of convergent evolution, that a limited number appear to be old trans-specific polymorphisms, and that balancing selection is affecting young and ancient mutations alike. Finally, we provide evidence that a blue wavelength opsin gene with trans-specific polymorphisms has functional effects on behavior and fitness in the wild. Ultimately, our findings provide insights into the genetic basis of adaptation and the maintenance of genetic diversity between species.
Collapse
Affiliation(s)
- Connor S. Murray
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Madison Karram
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - David J. Bass
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Madison Doceti
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Dörthe Becker
- Department of Biology, University of Virginia, Charlottesville, VA, USA
- School of Biosciences, Ecology and Evolutionary Biology, University of Sheffield, Sheffield, UK
| | | | - Aakrosh Ratan
- Center of Public Health Genomics, University of Virginia, Charlottesville, VA, USA
- Department of Public Health Sciences, University of Virginia, Charlottesville, VA, USA
| | - Alan O. Bergland
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| |
Collapse
|
4
|
Zhang Y, Li H, Wang Y, Nie M, Zhang K, Pan J, Zhang Y, Ye Z, Zufall RA, Lynch M, Long H. Mitogenomic architecture and evolution of the soil ciliates Colpoda. mSystems 2024; 9:e0116123. [PMID: 38259100 PMCID: PMC10878089 DOI: 10.1128/msystems.01161-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 12/14/2023] [Indexed: 01/24/2024] Open
Abstract
Colpoda are cosmopolitan unicellular eukaryotes primarily inhabiting soil and benefiting plant growth, but they remain one of the least understood taxa in genetics and genomics within the realm of ciliated protozoa. Here, we investigate the architecture of de novo assembled mitogenomes of six Colpoda species, using long-read sequencing and involving 36 newly isolated natural strains in total. The mitogenome sizes span from 43 to 63 kbp and typically contain 28-33 protein-coding genes. They possess a linear structure with variable telomeres and central repeats, with one Colpoda elliotti strain isolated from Tibet harboring the longest telomeres among all studied ciliates. Phylogenomic analyses reveal that Colpoda species started to diverge more than 326 million years ago, eventually evolving into two distinct groups. Collinearity analyses also reveal significant genomic divergences and a lack of long collinear blocks. One of the most notable features is the exceptionally high level of gene rearrangements between mitochondrial genomes of different Colpoda species, dominated by gene loss events. Population-level mitogenomic analysis on natural strains also demonstrates high sequence divergence, regardless of geographic distance, but the gene order remains highly conserved within species, offering a new species identification criterion for Colpoda species. Furthermore, we identified underlying heteroplasmic sites in the majority of strains of three Colpoda species, albeit without a discernible recombination signal to account for this heteroplasmy. This comprehensive study systematically unveils the mitogenomic structure and evolution of these ancient and ecologically significant Colpoda ciliates, thus laying the groundwork for a deeper understanding of the evolution of unicellular eukaryotes.IMPORTANCEColpoda, one of the most widespread ciliated protozoa in soil, are poorly understood in regard to their genetics and evolution. Our research revealed extreme mitochondrial gene rearrangements dominated by gene loss events, potentially leading to the streamlining of Colpoda mitogenomes. Surprisingly, while interspecific rearrangements abound, our population-level mitogenomic study revealed a conserved gene order within species, offering a potential new identification criterion. Phylogenomic analysis traced their lineage over 326 million years, revealing two distinct groups. Substantial genomic divergence might be associated with the lack of extended collinear blocks and relaxed purifying selection. This study systematically reveals Colpoda ciliate mitogenome structures and evolution, providing insights into the survival and evolution of these vital soil microorganisms.
Collapse
Affiliation(s)
- Yuanyuan Zhang
- Key Laboratory of Evolution and Marine Biodiversity (Ministry of Education), Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, Shandong Province, China
- Laboratory for Marine Biology and Biotechnology, Laoshan Laboratory, Qingdao, Shandong Province, China
| | - Haichao Li
- Key Laboratory of Evolution and Marine Biodiversity (Ministry of Education), Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, Shandong Province, China
| | - Yaohai Wang
- Key Laboratory of Evolution and Marine Biodiversity (Ministry of Education), Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, Shandong Province, China
| | - Mu Nie
- Key Laboratory of Evolution and Marine Biodiversity (Ministry of Education), Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, Shandong Province, China
| | - Kexin Zhang
- Key Laboratory of Evolution and Marine Biodiversity (Ministry of Education), Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, Shandong Province, China
| | - Jiao Pan
- Key Laboratory of Evolution and Marine Biodiversity (Ministry of Education), Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, Shandong Province, China
| | - Yu Zhang
- Key Laboratory of Evolution and Marine Biodiversity (Ministry of Education), Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, Shandong Province, China
- School of Mathematics Science, Ocean University of China, Qingdao, Shandong Province, China
| | - Zhiqiang Ye
- School of Life Sciences, Central China Normal University, Wuhan, Hubei Province, China
| | - Rebecca A. Zufall
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, USA
| | - Michael Lynch
- Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, Arizona, USA
| | - Hongan Long
- Key Laboratory of Evolution and Marine Biodiversity (Ministry of Education), Institute of Evolution and Marine Biodiversity, KLMME, Ocean University of China, Qingdao, Shandong Province, China
- Laboratory for Marine Biology and Biotechnology, Laoshan Laboratory, Qingdao, Shandong Province, China
| |
Collapse
|
5
|
Ye Z, Pfrender ME, Lynch M. Evolutionary Genomics of Sister Species Differing in Effective Population Sizes and Recombination Rates. Genome Biol Evol 2023; 15:evad202. [PMID: 37946625 PMCID: PMC10664402 DOI: 10.1093/gbe/evad202] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 10/16/2023] [Accepted: 11/02/2023] [Indexed: 11/12/2023] Open
Abstract
Studies of closely related species with known ecological differences provide exceptional opportunities for understanding the genetic mechanisms of evolution. In this study, we compared population-genomics data between Daphnia pulex and Daphnia pulicaria, two reproductively compatible sister species experiencing ecological speciation, the first largely confined to intermittent ponds and the second to permanent lakes in the same geographic region. Daphnia pulicaria has lower genome-wide nucleotide diversity, a smaller effective population size, a higher incidence of private alleles, and a substantially more linkage disequilibrium than D. pulex. Positively selected genes in D. pulicaria are enriched in potentially aging-related categories such as cellular homeostasis, which may explain the extended life span in D. pulicaria. We also found that opsin-related genes, which may mediate photoperiodic responses, are under different selection pressures in these two species. Genes involved in mitochondrial functions, ribosomes, and responses to environmental stimuli are found to be under positive selection in both species. Additionally, we found that the two species have similar average evolutionary rates at the DNA-sequence level, although approximately 160 genes have significantly different rates in the two lineages. Our results provide insights into the physiological traits that differ within this regionally sympatric sister-species pair that occupies unique microhabitats.
Collapse
Affiliation(s)
- Zhiqiang Ye
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Michael E Pfrender
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Michael Lynch
- Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, Arizona, USA
| |
Collapse
|
6
|
Stefano GB, Büttiker P, Weissenberger S, Esch T, Anders M, Raboch J, Kream RM, Ptacek R. Independent and sensory human mitochondrial functions reflecting symbiotic evolution. Front Cell Infect Microbiol 2023; 13:1130197. [PMID: 37389212 PMCID: PMC10302212 DOI: 10.3389/fcimb.2023.1130197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 05/31/2023] [Indexed: 07/01/2023] Open
Abstract
The bacterial origin of mitochondria has been a widely accepted as an event that occurred about 1.45 billion years ago and endowed cells with internal energy producing organelle. Thus, mitochondria have traditionally been viewed as subcellular organelle as any other - fully functionally dependent on the cell it is a part of. However, recent studies have given us evidence that mitochondria are more functionally independent than other organelles, as they can function outside the cells, engage in complex "social" interactions, and communicate with each other as well as other cellular components, bacteria and viruses. Furthermore, mitochondria move, assemble and organize upon sensing different environmental cues, using a process akin to bacterial quorum sensing. Therefore, taking all these lines of evidence into account we hypothesize that mitochondria need to be viewed and studied from a perspective of a more functionally independent entity. This view of mitochondria may lead to new insights into their biological function, and inform new strategies for treatment of disease associated with mitochondrial dysfunction.
Collapse
Affiliation(s)
- George B. Stefano
- Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czechia
| | - Pascal Büttiker
- Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czechia
| | | | - Tobias Esch
- Institute for Integrative Health Care and Health Promotion, School of Medicine, Witten/Herdecke University, Witten, Germany
| | - Martin Anders
- Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czechia
| | - Jiri Raboch
- Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czechia
| | - Richard M. Kream
- Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czechia
| | - Radek Ptacek
- Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czechia
| |
Collapse
|
7
|
Abstract
The ways in which genetic variation is distributed within and among populations is a key determinant of the evolutionary features of a species. However, most comprehensive studies of these features have been restricted to studies of subdivision in settings known to have been driven by local adaptation, leaving our understanding of the natural dispersion of allelic variation less than ideal. Here, we present a geographic population-genomic analysis of 10 populations of the freshwater microcrustacean Daphnia pulex, an emerging model system in evolutionary genomics. These populations exhibit a pattern of moderate isolation-by-distance, with an average migration rate of 0.6 individuals per generation, and average effective population sizes of ∼650,000 individuals. Most populations contain numerous private alleles, and genomic scans highlight the presence of islands of excessively high population subdivision for more common alleles. A large fraction of such islands of population divergence likely reflect historical neutral changes, including rare stochastic migration and hybridization events. The data do point to local adaptive divergence, although the precise nature of the relevant variation is diffuse and cannot be associated with particular loci, despite the very large sample sizes involved in this study. In contrast, an analysis of between-species divergence highlights positive selection operating on a large set of genes with functions nearly nonoverlapping with those involved in local adaptation, in particular ribosome structure, mitochondrial bioenergetics, light reception and response, detoxification, and gene regulation. These results set the stage for using D. pulex as a model for understanding the relationship between molecular and cellular evolution in the context of natural environments.
Collapse
Affiliation(s)
- Takahiro Maruki
- Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, AZ 85287, USA
| | - Zhiqiang Ye
- Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, AZ 85287, USA
| | - Michael Lynch
- Biodesign Center for Mechanisms of Evolution, Arizona State University, Tempe, AZ 85287, USA
| |
Collapse
|