1
|
Park S, An B, Park S. Dynamic changes in the plastid and mitochondrial genomes of the angiosperm Corydalis pauciovulata (Papaveraceae). BMC PLANT BIOLOGY 2024; 24:303. [PMID: 38644497 PMCID: PMC11034061 DOI: 10.1186/s12870-024-05025-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 04/15/2024] [Indexed: 04/23/2024]
Abstract
BACKGROUND Corydalis DC., the largest genus in the family Papaveraceae, comprises > 465 species. Complete plastid genomes (plastomes) of Corydalis show evolutionary changes, including syntenic arrangements, gene losses and duplications, and IR boundary shifts. However, little is known about the evolution of the mitochondrial genome (mitogenome) in Corydalis. Both the organelle genomes and transcriptomes are needed to better understand the relationships between the patterns of evolution in mitochondrial and plastid genomes. RESULTS We obtained complete plastid and mitochondrial genomes from Corydalis pauciovulata using a hybrid assembly of Illumina and Oxford Nanopore Technologies reads to assess the evolutionary parallels between the organelle genomes. The mitogenome and plastome of C. pauciovulata had sizes of 675,483 bp and 185,814 bp, respectively. Three ancestral gene clusters were missing from the mitogenome, and expanded IR (46,060 bp) and miniaturized SSC (202 bp) regions were identified in the plastome. The mitogenome and plastome of C. pauciovulata contained 41 and 67 protein-coding genes, respectively; the loss of genes was a plastid-specific event. We also generated a draft genome and transcriptome for C. pauciovulata. A combination of genomic and transcriptomic data supported the functional replacement of acetyl-CoA carboxylase subunit β (accD) by intracellular transfer to the nucleus in C. pauciovulata. In contrast, our analyses suggested a concurrent loss of the NADH-plastoquinone oxidoreductase (ndh) complex in both the nuclear and plastid genomes. Finally, we performed genomic and transcriptomic analyses to characterize DNA replication, recombination, and repair (DNA-RRR) genes in C. pauciovulata as well as the transcriptomes of Liriodendron tulipifera and Nelumbo nuicifera. We obtained 25 DNA-RRR genes and identified their structure in C. pauciovulata. Pairwise comparisons of nonsynonymous (dN) and synonymous (dS) substitution rates revealed that several DNA-RRR genes in C. pauciovulata have higher dN and dS values than those in N. nuicifera. CONCLUSIONS The C. pauciovulata genomic data generated here provide a valuable resource for understanding the evolution of Corydalis organelle genomes. The first mitogenome of Papaveraceae provides an example that can be explored by other researchers sequencing the mitogenomes of related plants. Our results also provide fundamental information about DNA-RRR genes in Corydalis and their related rate variation, which elucidates the relationships between DNA-RRR genes and organelle genome stability.
Collapse
Affiliation(s)
- Seongjun Park
- Institute of Natural Science, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, South Korea.
| | - Boram An
- Department of Life Sciences, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, South Korea
| | - SeonJoo Park
- Department of Life Sciences, Yeungnam University, Gyeongsan, Gyeongbuk, 38541, South Korea.
| |
Collapse
|
2
|
Fu CN, Wicke S, Zhu AD, Li DZ, Gao LM. Distinctive plastome evolution in carnivorous angiosperms. BMC PLANT BIOLOGY 2023; 23:660. [PMID: 38124058 PMCID: PMC10731798 DOI: 10.1186/s12870-023-04682-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 12/11/2023] [Indexed: 12/23/2023]
Abstract
BACKGROUND Independent origins of carnivory in multiple angiosperm families are fabulous examples of convergent evolution using a diverse array of life forms and habitats. Previous studies have indicated that carnivorous plants have distinct evolutionary trajectories of plastid genome (plastome) compared to their non-carnivorous relatives, yet the extent and general characteristics remain elusive. RESULTS We compared plastomes from 9 out of 13 carnivorous families and their non-carnivorous relatives to assess carnivory-associated evolutionary patterns. We identified inversions in all sampled Droseraceae species and four species of Utricularia, Pinguicula, Darlingtonia and Triphyophyllum. A few carnivores showed distinct shifts in inverted repeat boundaries and the overall repeat contents. Many ndh genes, along with some other genes, were independently lost in several carnivorous lineages. We detected significant substitution rate variations in most sampled carnivorous lineages. A significant overall substitution rate acceleration characterizes the two largest carnivorous lineages of Droseraceae and Lentibulariaceae. We also observe moderate substitution rates acceleration in many genes of Cephalotus follicularis, Roridula gorgonias, and Drosophyllum lusitanicum. However, only a few genes exhibit significant relaxed selection. CONCLUSION Our results indicate that the carnivory of plants have different effects on plastome evolution across carnivorous lineages. The complex mechanism under carnivorous habitats may have resulted in distinctive plastome evolution with conserved plastome in the Brocchinia hechtioides to strongly reconfigured plastomes structures in Droseraceae. Organic carbon obtained from prey and the efficiency of utilizing prey-derived nutrients might constitute possible explanation.
Collapse
Affiliation(s)
- Chao-Nan Fu
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China
- Lijiang Forest Biodiversity National Observation and Research Station, Kunming Institute of Botany, Chinese Academy of Sciences, Lijiang, 674100, Yunnan, China
| | - Susann Wicke
- Institute for Biology, Humboldt-University Berlin, Berlin, Germany
- Späth-Arboretum of the Humboldt-University Berlin, Berlin, Germany
| | - An-Dan Zhu
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China
| | - De-Zhu Li
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China
| | - Lian-Ming Gao
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China.
- Lijiang Forest Biodiversity National Observation and Research Station, Kunming Institute of Botany, Chinese Academy of Sciences, Lijiang, 674100, Yunnan, China.
| |
Collapse
|
3
|
Turudić A, Liber Z, Grdiša M, Jakše J, Varga F, Šatović Z. Chloroplast Genome Annotation Tools: Prolegomena to the Identification of Inverted Repeats. Int J Mol Sci 2022; 23:ijms231810804. [PMID: 36142721 PMCID: PMC9503105 DOI: 10.3390/ijms231810804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 09/01/2022] [Accepted: 09/13/2022] [Indexed: 12/31/2022] Open
Abstract
The development of next-generation sequencing technology and the increasing amount of sequencing data have brought the bioinformatic tools used in genome assembly into focus. The final step of the process is genome annotation, which works on assembled genome sequences to identify the location of genome features. In the case of organelle genomes, specialized annotation tools are used to identify organelle genes and structural features. Numerous annotation tools target chloroplast sequences. Most chloroplast DNA genomes have a quadripartite structure caused by two copies of a large inverted repeat. We investigated the strategies of six annotation tools (Chloë, Chloroplot, GeSeq, ORG.Annotate, PGA, Plann) for identifying inverted repeats and analyzed their success using publicly available complete chloroplast sequences of taxa belonging to the asterid and rosid clades. The annotation tools use two different approaches to identify inverted repeats, using existing general search tools or implementing stand-alone solutions. The chloroplast sequences studied show that there are different types of imperfections in the assembled data and that each tool performs better on some sequences than the others.
Collapse
Affiliation(s)
- Ante Turudić
- Centre of Excellence for Biodiversity and Molecular Plant Breeding (CoE CroP-BioDiv), Svetošimunska cesta 25, 10000 Zagreb, Croatia
- Faculty of Agriculture, University of Zagreb, Svetošimunska cesta 25, 10000 Zagreb, Croatia
- Correspondence: ; Tel.: +385-91-3141592
| | - Zlatko Liber
- Faculty of Agriculture, University of Zagreb, Svetošimunska cesta 25, 10000 Zagreb, Croatia
- Faculty of Science, University of Zagreb, Marulićev trg 9a, 10000 Zagreb, Croatia
| | - Martina Grdiša
- Centre of Excellence for Biodiversity and Molecular Plant Breeding (CoE CroP-BioDiv), Svetošimunska cesta 25, 10000 Zagreb, Croatia
- Faculty of Agriculture, University of Zagreb, Svetošimunska cesta 25, 10000 Zagreb, Croatia
| | - Jernej Jakše
- Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia
| | - Filip Varga
- Centre of Excellence for Biodiversity and Molecular Plant Breeding (CoE CroP-BioDiv), Svetošimunska cesta 25, 10000 Zagreb, Croatia
- Faculty of Agriculture, University of Zagreb, Svetošimunska cesta 25, 10000 Zagreb, Croatia
| | - Zlatko Šatović
- Centre of Excellence for Biodiversity and Molecular Plant Breeding (CoE CroP-BioDiv), Svetošimunska cesta 25, 10000 Zagreb, Croatia
- Faculty of Agriculture, University of Zagreb, Svetošimunska cesta 25, 10000 Zagreb, Croatia
| |
Collapse
|
4
|
Ceriotti LF, Gatica-Soria L, Sanchez-Puerta MV. Cytonuclear coevolution in a holoparasitic plant with highly disparate organellar genomes. PLANT MOLECULAR BIOLOGY 2022; 109:673-688. [PMID: 35359176 DOI: 10.1007/s11103-022-01266-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 03/18/2022] [Indexed: 06/14/2023]
Abstract
Contrasting substitution rates in the organellar genomes of Lophophytum agree with the DNA repair, replication, and recombination gene content. Plastid and nuclear genes whose products form multisubunit complexes co-evolve. The organellar genomes of the holoparasitic plant Lophophytum (Balanophoraceae) show disparate evolution. In the plastid, the genome has been severely reduced and presents a > 85% AT content, while in the mitochondria most protein-coding genes have been replaced by homologs acquired by horizontal gene transfer (HGT) from their hosts (Fabaceae). Both genomes carry genes whose products form multisubunit complexes with those of nuclear genes, creating a possible hotspot of cytonuclear coevolution. In this study, we assessed the evolutionary rates of plastid, mitochondrial and nuclear genes, and their impact on cytonuclear evolution of genes involved in multisubunit complexes related to lipid biosynthesis and proteolysis in the plastid and those in charge of the oxidative phosphorylation in the mitochondria. Genes from the plastid and the mitochondria (both native and foreign) of Lophophytum showed extremely high and ordinary substitution rates, respectively. These results agree with the biased loss of plastid-targeted proteins involved in angiosperm organellar repair, replication, and recombination machinery. Consistent with the high rate of evolution of plastid genes, nuclear-encoded subunits of plastid complexes showed disproportionate increases in non-synonymous substitution rates, while those of the mitochondrial complexes did not show different rates than the control (i.e. non-organellar nuclear genes). Moreover, the increases in the nuclear-encoded subunits of plastid complexes were positively correlated with the level of physical interaction they possess with the plastid-encoded ones. Overall, these results suggest that a structurally-mediated compensatory factor may be driving plastid-nuclear coevolution in Lophophytum, and that mito-nuclear coevolution was not altered by HGT.
Collapse
Affiliation(s)
- Luis F Ceriotti
- Facultad de Ciencias Agrarias, IBAM, Universidad Nacional de Cuyo, CONICET, Almirante Brown 500, Chacras de Coria, M5528AHB, Mendoza, Argentina
- Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Padre Jorge Contreras 1300, M5502JMA, Mendoza, Argentina
| | - Leonardo Gatica-Soria
- Facultad de Ciencias Agrarias, IBAM, Universidad Nacional de Cuyo, CONICET, Almirante Brown 500, Chacras de Coria, M5528AHB, Mendoza, Argentina
- Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Padre Jorge Contreras 1300, M5502JMA, Mendoza, Argentina
| | - M Virginia Sanchez-Puerta
- Facultad de Ciencias Agrarias, IBAM, Universidad Nacional de Cuyo, CONICET, Almirante Brown 500, Chacras de Coria, M5528AHB, Mendoza, Argentina.
- Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Padre Jorge Contreras 1300, M5502JMA, Mendoza, Argentina.
| |
Collapse
|
5
|
Xiang QP, Tang JY, Yu JG, Smith DR, Zhu YM, Wang YR, Kang JS, Yang J, Zhang XC. The evolution of extremely diverged plastomes in Selaginellaceae (lycophyte) is driven by repeat patterns and the underlying DNA maintenance machinery. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 111:768-784. [PMID: 35648423 DOI: 10.1111/tpj.15851] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/25/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
Two factors are proposed to account for the unusual features of organellar genomes: the disruptions of organelle-targeted DNA replication, repair, and recombination (DNA-RRR) systems in the nuclear genome and repetitive elements in organellar genomes. Little is known about how these factors affect organellar genome evolution. The deep-branching vascular plant family Selaginellaceae is known to have a deficient DNA-RRR system and convergently evolved organellar genomes. However, we found that the plastid genome (plastome) of Selaginella sinensis has extremely accelerated substitution rates, a low GC content, pervasive repeat elements, a dynamic network structure, and it lacks direct or inverted repeats. Unexpectedly, its organelle DNA-RRR system is short of a plastid-targeted Recombinase A1 (RecA1) and a mitochondrion-targeted RecA3, in line with other explored Selaginella species. The plastome contains a large collection of short- and medium-sized repeats. Given the absence of RecA1 surveillance, we propose that these repeats trigger illegitimate recombination, accelerated mutation rates, and structural instability. The correlations between repeat quantity and architectural complexity in the Selaginella plastomes support these conclusions. We, therefore, hypothesize that the interplay of the deficient DNA-RRR system and the high repeat content has led to the extraordinary divergence of the S. sinensis plastome. Our study not only sheds new light on the mechanism of plastome divergence by emphasizing the power of cytonuclear integration, but it also reconciles the longstanding contradiction on the effects of DNA-RRR system disruption on genome structure evolution.
Collapse
Affiliation(s)
- Qiao-Ping Xiang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
| | - Jun-Yong Tang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ji-Gao Yu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - David Roy Smith
- Department of Biology, University of Western Ontario, London, N6A 5B7, Ontario, Canada
| | - Yan-Mei Zhu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
| | - Ya-Rong Wang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
| | - Jong-Soo Kang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
| | - Jie Yang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xian-Chun Zhang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, The Chinese Academy of Sciences, Beijing, 100093, China
| |
Collapse
|
6
|
Fonseca LHM, Nazareno AG, Thode VA, Zuntini AR, Lohmann LG. Putting small and big pieces together: a genome assembly approach reveals the largest Lamiid plastome in a woody vine. PeerJ 2022; 10:e13207. [PMID: 35415013 PMCID: PMC8995027 DOI: 10.7717/peerj.13207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 03/10/2022] [Indexed: 01/12/2023] Open
Abstract
The plastid genome of flowering plants generally shows conserved structural organization, gene arrangement, and gene content. While structural reorganizations are uncommon, examples have been documented in the literature during the past years. Here we assembled the entire plastome of Bignonia magnifica and compared its structure and gene content with nine other Lamiid plastomes. The plastome of B. magnifica is composed of 183,052 bp and follows the canonical quadripartite structure, synteny, and gene composition of other angiosperms. Exceptionally large inverted repeat (IR) regions are responsible for the uncommon length of the genome. At least four events of IR expansion were observed among the seven Bignoniaceae species compared, suggesting multiple expansions of the IRs over the SC regions in the family. A comparison with 6,231 other complete plastomes of flowering plants available on GenBank revealed that the plastome of B. magnifica is the longest Lamiid plastome described to date. The newly generated plastid genome was used as a source of selected genes. These genes were combined with orthologous regions sampled from other species of Bignoniaceae and all gene alignments concatenated to infer a phylogeny of the family. The tree recovered is consistent with known relationships within the Bignoniaceae.
Collapse
Affiliation(s)
- Luiz Henrique M. Fonseca
- Instituto de Biocências, Universidade de São Paulo, São Paulo, Brazil,Department of Biology, Ghent University, Ghent, Flanders, Belgium
| | - Alison G. Nazareno
- Instituto de Biocências, Universidade de São Paulo, São Paulo, Brazil,Departamento de Genética, Ecologia e Evolução, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Verônica A. Thode
- Instituto de Biocências, Universidade de São Paulo, São Paulo, Brazil,Departamento de Botânica, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Alexandre R. Zuntini
- Instituto de Biocências, Universidade de São Paulo, São Paulo, Brazil,Royal Botanic Gardens, Kew, London, United Kingdom
| | - Lúcia G. Lohmann
- Instituto de Biocências, Universidade de São Paulo, São Paulo, Brazil
| |
Collapse
|
7
|
Comparative Plastome Analysis of Three Amaryllidaceae Subfamilies: Insights into Variation of Genome Characteristics, Phylogeny, and Adaptive Evolution. BIOMED RESEARCH INTERNATIONAL 2022; 2022:3909596. [PMID: 35372568 PMCID: PMC8970886 DOI: 10.1155/2022/3909596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 01/19/2022] [Accepted: 02/05/2022] [Indexed: 11/17/2022]
Abstract
In the latest APG IV classification system, Amaryllidaceae is placed under the order of Asparagus and includes three subfamilies: Agapanthoideae, Allioideae, and Amaryllidoideae, which include many economically important crops. With the development of molecular phylogeny, research on the phylogenetic relationship of Amaryllidaceae has become more convenient. However, the current comparative analysis of Amaryllidaceae at the whole chloroplast genome level is still lacking. In this study, we sequenced 18 Allioideae plastomes and combined them with publicly available data (a total of 41 plastomes), including 21 Allioideae species, 1 Agapanthoideae species, 14 Amaryllidoideae species, and 5 Asparagaceae species. Comparative analyses were performed including basic characteristics of genome structure, codon usage, repeat elements, IR boundary, and genome divergence. Phylogenetic relationships were detected using single-copy genes (SCGs) and ribosomal internal transcribed spacer sequences (ITS), and the branch-site model was also employed to conduct the positive selection analysis. The results indicated that all Amaryllidaceae species showed a highly conserved typical tetrad structure. The GC content and five codon usage indexes in Allioideae species were lower than those in the other two subfamilies. Comparison analysis of Bayesian and ML phylogeny based on SCGs strongly supports the monophyly of three subfamilies and the sisterhood among them. Besides, positively selected genes (PSGs) were detected in each of the three subfamilies. Almost all genes with significant posterior probabilities for codon sites were associated with self-replication and photosynthesis. Our study investigated the three subfamilies of Amaryllidaceae at the whole chloroplast genome level and suggested the key role of selective pressure in the adaptation and evolution of Amaryllidaceae.
Collapse
|
8
|
Lencina F, Landau A, Prina AR. The Barley Chloroplast Mutator (cpm) Mutant: All Roads Lead to the Msh1 Gene. Int J Mol Sci 2022; 23:ijms23031814. [PMID: 35163736 PMCID: PMC8836938 DOI: 10.3390/ijms23031814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 11/11/2021] [Accepted: 11/19/2021] [Indexed: 12/10/2022] Open
Abstract
The barley chloroplast mutator (cpm) is a nuclear gene mutant that induces a wide spectrum of cytoplasmically inherited chlorophyll deficiencies. Plastome instability of cpm seedlings was determined by identification of a particular landscape of polymorphisms that suggests failures in a plastome mismatch repair (MMR) protein. In Arabidopsis, MSH genes encode proteins that are in charge of mismatch repair and have anti-recombination activity. In this work, barley homologs of these genes were identified, and their sequences were analyzed in control and cpm mutant seedlings. A substitution, leading to a premature stop codon and a truncated MSH1 protein, was identified in the Msh1 gene of cpm plants. The relationship between this mutation and the presence of chlorophyll deficiencies was established in progenies from crosses and backcrosses. These results strongly suggest that the mutation identified in the Msh1 gene of the cpm mutant is responsible for the observed plastome instabilities. Interestingly, comparison of mutant phenotypes and molecular changes induced by the barley cpm mutant with those of Arabidopsis MSH1 mutants revealed marked differences.
Collapse
|
9
|
Abdel-Ghany SE, LaManna LM, Harroun HT, Maliga P, Sloan DB. Rapid sequence evolution is associated with genetic incompatibilities in the plastid Clp complex. PLANT MOLECULAR BIOLOGY 2022; 108:277-287. [PMID: 35039977 DOI: 10.1007/s11103-022-01241-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 12/23/2021] [Indexed: 06/14/2023]
Abstract
KEY MESSAGE Replacing the native clpP1 gene in the Nicotiana plastid genome with homologs from different donor species showed that the extent of genetic incompatibilities depended on the rate of sequence evolution. The plastid caseinolytic protease (Clp) complex plays essential roles in maintaining protein homeostasis and comprises both plastid-encoded and nuclear-encoded subunits. Despite the Clp complex being retained across green plants with highly conserved protein sequences in most species, examples of extremely accelerated amino acid substitution rates have been identified in numerous angiosperms. The causes of these accelerations have been the subject of extensive speculation but still remain unclear. To distinguish among prevailing hypotheses and begin to understand the functional consequences of rapid sequence divergence in Clp subunits, we used plastome transformation to replace the native clpP1 gene in tobacco (Nicotiana tabacum) with counterparts from another angiosperm genus (Silene) that exhibits a wide range in rates of Clp protein sequence evolution. We found that antibiotic-mediated selection could drive a transgenic clpP1 replacement from a slowly evolving donor species (S. latifolia) to homoplasmy but that clpP1 copies from Silene species with accelerated evolutionary rates remained heteroplasmic, meaning that they could not functionally replace the essential tobacco clpP1 gene. These results suggest that observed cases of rapid Clp sequence evolution are a source of epistatic incompatibilities that must be ameliorated by coevolutionary responses between plastid and nuclear subunits.
Collapse
Affiliation(s)
- Salah E Abdel-Ghany
- Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA.
| | - Lisa M LaManna
- Waksman Institute of Microbiology, Rutgers University, Piscataway, NJ, 08854, USA
| | - Haleakala T Harroun
- Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Pal Maliga
- Waksman Institute of Microbiology, Rutgers University, Piscataway, NJ, 08854, USA
- Department of Plant Biology, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA.
| |
Collapse
|
10
|
The minicircular and extremely heteroplasmic mitogenome of the holoparasitic plant Rhopalocnemis phalloides. Curr Biol 2021; 32:470-479.e5. [PMID: 34906352 DOI: 10.1016/j.cub.2021.11.053] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 10/25/2021] [Accepted: 11/22/2021] [Indexed: 12/14/2022]
Abstract
The plastid and nuclear genomes of parasitic plants exhibit deeply altered architectures,1-13 whereas the few examined mitogenomes range from deeply altered to conventional.14-20 To provide further insight on mitogenome evolution in parasitic plants, we report the highly modified mitogenome of Rhopalocnemis phalloides, a holoparasite in Balanophoraceae. Its mitogenome is uniquely arranged in 21 minicircular chromosomes that vary in size from 4,949 to 7,861 bp, with a total length of only 130,713 bp. All chromosomes share an identical 896 bp conserved region, with a large stem-loop that acts as the origin of replication, flanked on each side by hypervariable and semi-conserved regions. Similar minicircular structures with shared and unique regions have been observed in parasitic animals and free-living protists,21-24 suggesting convergent structural evolution. Southern blots confirm both the minicircular structure and the replication origin of the mitochondrial chromosomes. PacBio reads provide evidence for chromosome recombination and rolling-circle replication for the R. phalloides mitogenome. Despite its small size, the mitogenome harbors a typical set of genes and introns within the unique regions of each chromosome, yet introns are the smallest among seed plants and ferns. The mitogenome also exhibits extreme heteroplasmy, predominantly involving short indels and more complex variants, many of which cause potential loss-of-function mutations for some gene copies. All heteroplasmic variants are transcribed, and functional and nonfunctional protein-coding variants are spliced and RNA edited. Our findings offer a unique perspective into how mitogenomes of parasitic plants can be deeply altered and shed light on plant mitogenome replication.
Collapse
|
11
|
Lee C, Choi IS, Cardoso D, de Lima HC, de Queiroz LP, Wojciechowski MF, Jansen RK, Ruhlman TA. The chicken or the egg? Plastome evolution and an independent loss of the inverted repeat in papilionoid legumes. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 107:861-875. [PMID: 34021942 DOI: 10.1111/tpj.15351] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/22/2021] [Accepted: 05/03/2021] [Indexed: 06/12/2023]
Abstract
The plastid genome (plastome), while surprisingly constant in gene order and content across most photosynthetic angiosperms, exhibits variability in several unrelated lineages. During the diversification history of the legume family Fabaceae, plastomes have undergone many rearrangements, including inversions, expansion, contraction and loss of the typical inverted repeat (IR), gene loss and repeat accumulation in both shared and independent events. While legume plastomes have been the subject of study for some time, most work has focused on agricultural species in the IR-lacking clade (IRLC) and the plant model Medicago truncatula. The subfamily Papilionoideae, which contains virtually all of the agricultural legume species, also comprises most of the plastome variation detected thus far in the family. In this study three non-papilioniods were included among 34 newly sequenced legume plastomes, along with 33 publicly available sequences, to assess plastome structural evolution in the subfamily. In an effort to examine plastome variation across the subfamily, approximately 20% of the sampling represents the IRLC with the remainder selected to represent the early-branching papilionoid clades. A number of IR-related and repeat-mediated changes were identified and examined in a phylogenetic context. Recombination between direct repeats associated with ycf2 resulted in intraindividual plastome heteroplasmy. Although loss of the IR has not been reported in legumes outside of the IRLC, one genistoid taxon was found to completely lack the typical plastome IR. The role of the IR and non-IR repeats in the progression of plastome change is discussed.
Collapse
Affiliation(s)
- Chaehee Lee
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - In-Su Choi
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287-4501, USA
| | - Domingos Cardoso
- Instituto de Biologia, Universidade Federal de Bahia (UFBA), Rua Barão de Jeremoabo, s.n., Ondina, Salvador, Bahia, 40170-115, Brazil
| | - Haroldo C de Lima
- Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rua Pacheco Leão, Rio de Janeiro, 915 22460-030, Brazil
| | - Luciano P de Queiroz
- Universidade Estadual de Feira de Santana, Av. Transnordestina, s/n, Novo Horizonte, Feira de Santana, Bahia, 44036-900, Brazil
| | | | - Robert K Jansen
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
- Center of Excellence for Bionanoscience Research, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
| | - Tracey A Ruhlman
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| |
Collapse
|
12
|
Lee C, Ruhlman TA, Jansen RK. Unprecedented Intraindividual Structural Heteroplasmy in Eleocharis (Cyperaceae, Poales) Plastomes. Genome Biol Evol 2021; 12:641-655. [PMID: 32282915 PMCID: PMC7426004 DOI: 10.1093/gbe/evaa076] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/07/2020] [Indexed: 12/13/2022] Open
Abstract
Plastid genomes (plastomes) of land plants have a conserved quadripartite structure in a gene-dense unit genome consisting of a large inverted repeat that separates two single copy regions. Recently, alternative plastome structures were suggested in Geraniaceae and in some conifers and Medicago the coexistence of inversion isomers has been noted. In this study, plastome sequences of two Cyperaceae, Eleocharis dulcis (water chestnut) and Eleocharis cellulosa (gulf coast spikerush), were completed. Unlike the conserved plastomes in basal groups of Poales, these Eleocharis plastomes have remarkably divergent features, including large plastome sizes, high rates of sequence rearrangements, low GC content and gene density, gene duplications and losses, and increased repetitive DNA sequences. A novel finding among these features was the unprecedented level of heteroplasmy with the presence of multiple plastome structural types within a single individual. Illumina paired-end assemblies combined with PacBio single-molecule real-time sequencing, long-range polymerase chain reaction, and Sanger sequencing data identified at least four different plastome structural types in both Eleocharis species. PacBio long read data suggested that one of the four E. dulcis plastome types predominates.
Collapse
Affiliation(s)
- Chaehee Lee
- Department of Integrative Biology, University of Texas at Austin
| | - Tracey A Ruhlman
- Department of Integrative Biology, University of Texas at Austin
| | - Robert K Jansen
- Department of Integrative Biology, University of Texas at Austin.,Center of Excellence for Bionanoscience Research, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
| |
Collapse
|
13
|
Forsythe ES, Williams AM, Sloan DB. Genome-wide signatures of plastid-nuclear coevolution point to repeated perturbations of plastid proteostasis systems across angiosperms. THE PLANT CELL 2021; 33:980-997. [PMID: 33764472 PMCID: PMC8226287 DOI: 10.1093/plcell/koab021] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 01/16/2021] [Indexed: 05/05/2023]
Abstract
Nuclear and plastid (chloroplast) genomes experience different mutation rates, levels of selection, and transmission modes, yet key cellular functions depend on their coordinated interactions. Functionally related proteins often show correlated changes in rates of sequence evolution across a phylogeny [evolutionary rate covariation (ERC)], offering a means to detect previously unidentified suites of coevolving and cofunctional genes. We performed phylogenomic analyses across angiosperm diversity, scanning the nuclear genome for genes that exhibit ERC with plastid genes. As expected, the strongest hits were highly enriched for genes encoding plastid-targeted proteins, providing evidence that cytonuclear interactions affect rates of molecular evolution at genome-wide scales. Many identified nuclear genes functioned in post-transcriptional regulation and the maintenance of protein homeostasis (proteostasis), including protein translation (in both the plastid and cytosol), import, quality control, and turnover. We also identified nuclear genes that exhibit strong signatures of coevolution with the plastid genome, but their encoded proteins lack organellar-targeting annotations, making them candidates for having previously undescribed roles in plastids. In sum, our genome-wide analyses reveal that plastid-nuclear coevolution extends beyond the intimate molecular interactions within chloroplast enzyme complexes and may be driven by frequent rewiring of the machinery responsible for maintenance of plastid proteostasis in angiosperms.
Collapse
Affiliation(s)
- Evan S Forsythe
- Department of Biology, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Alissa M Williams
- Department of Biology, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, Colorado 80523, USA
| |
Collapse
|
14
|
de Santana Lopes A, Gomes Pacheco T, Nascimento da Silva O, do Nascimento Vieira L, Guerra MP, Pacca Luna Mattar E, de Baura VA, Balsanelli E, Maltempi de Souza E, de Oliveira Pedrosa F, Rogalski M. Plastid genome evolution in Amazonian açaí palm (Euterpe oleracea Mart.) and Atlantic forest açaí palm (Euterpe edulis Mart.). PLANT MOLECULAR BIOLOGY 2021; 105:559-574. [PMID: 33386578 DOI: 10.1007/s11103-020-01109-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Accepted: 12/15/2020] [Indexed: 06/12/2023]
Abstract
The plastomes of E. edulis and E. oleracea revealed several molecular markers useful for genetic studies in natural populations and indicate specific evolutionary features determined by vicariant speciation. Arecaceae is a large and diverse family occurring in tropical and subtropical ecosystems worldwide. E. oleracea is a hyperdominant species of the Amazon forest, while E. edulis is a keystone species of the Atlantic forest. It has reported that E. edulis arose from vicariant speciation after the emergence of the belt barrier of dry environment (Cerrado and Caatinga biomes) between Amazon and Atlantic forests, isolating the E. edulis in the Atlantic forest. We sequenced the complete plastomes of E. edulis and E. oleracea and compared them concerning plastome structure, SSRs, tandem repeats, SNPs, indels, hotspots of nucleotide polymorphism, codon Ka/Ks ratios and RNA editing sites aiming to investigate evolutionary traits possibly affected by distinct environments. Our analyses revealed 303 SNPs, 91 indels, and 82 polymorphic SSRs among both species. Curiously, the narrow correlation among localization of repetitive sequences and indels strongly suggests that replication slippage is involved in plastid DNA mutations in Euterpe. Moreover, most non-synonymous substitutions represent amino acid variants in E. edulis that evolved specifically or in a convergent manner across the palm phylogeny. Amino acid variants observed in several plastid proteins in E. edulis were also identified as positive signatures across palm phylogeny. The higher incidence of specific amino acid changes in plastid genes of E. edulis in comparison with E. oleracea probably configures adaptive genetic variations determined by vicariant speciation. Our data indicate that the environment generates a selective pressure on the plastome making it more adapted to specific conditions.
Collapse
Affiliation(s)
- Amanda de Santana Lopes
- Laboratório de Fisiologia Molecular de Plantas, Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | - Túlio Gomes Pacheco
- Laboratório de Fisiologia Molecular de Plantas, Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | - Odyone Nascimento da Silva
- Laboratório de Fisiologia Molecular de Plantas, Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | - Leila do Nascimento Vieira
- Laboratório de Fisiologia do Desenvolvimento e Genética Vegetal, Programa de Pós-graduação em Recursos Genéticos Vegetais, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | - Miguel Pedro Guerra
- Laboratório de Fisiologia do Desenvolvimento e Genética Vegetal, Programa de Pós-graduação em Recursos Genéticos Vegetais, Universidade Federal de Santa Catarina, Florianópolis, SC, Brazil
| | | | - Valter Antonio de Baura
- Departamento de Bioquímica e Biologia Molecular, Núcleo de Fixação Biológica de Nitrogênio, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Eduardo Balsanelli
- Departamento de Bioquímica e Biologia Molecular, Núcleo de Fixação Biológica de Nitrogênio, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Emanuel Maltempi de Souza
- Departamento de Bioquímica e Biologia Molecular, Núcleo de Fixação Biológica de Nitrogênio, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Fábio de Oliveira Pedrosa
- Departamento de Bioquímica e Biologia Molecular, Núcleo de Fixação Biológica de Nitrogênio, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Marcelo Rogalski
- Laboratório de Fisiologia Molecular de Plantas, Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
| |
Collapse
|
15
|
Abstract
The plastid genome (plastome ) has proved a valuable source of data for evaluating evolutionary relationships among angiosperms. Through basic and applied approaches, plastid transformation technology offers the potential to understand and improve plant productivity, providing food, fiber, energy, and medicines to meet the needs of a burgeoning global population. The growing genomic resources available to both phylogenetic and biotechnological investigations is allowing novel insights and expanding the scope of plastome research to encompass new species. In this chapter, we present an overview of some of the seminal and contemporary research that has contributed to our current understanding of plastome evolution and attempt to highlight the relationship between evolutionary mechanisms and the tools of plastid genetic engineering.
Collapse
Affiliation(s)
- Tracey A Ruhlman
- Integrative Biology, University of Texas at Austin, Austin, TX, USA.
| | - Robert K Jansen
- Integrative Biology, University of Texas at Austin, Austin, TX, USA
| |
Collapse
|
16
|
Choi K, Weng ML, Ruhlman TA, Jansen RK. Extensive variation in nucleotide substitution rate and gene/intron loss in mitochondrial genomes of Pelargonium. Mol Phylogenet Evol 2020; 155:106986. [PMID: 33059063 DOI: 10.1016/j.ympev.2020.106986] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 07/16/2020] [Accepted: 10/07/2020] [Indexed: 12/30/2022]
Abstract
Geraniaceae organelle genomes have been shown to exhibit several highly unusual features compared to most other photosynthetic angiosperms. This includes massively rearranged plastomes with considerable size variation, extensive gene and intron loss, accelerated rates of nucleotide substitutions in both mitogenomes and plastomes, and biparental inheritance and cytonuclear incompatibility of the plastome. Most previous studies have focused on plastome evolution with mitogenome comparisons limited to only a few taxa or genes. In this study, mitogenomes and transcriptomes were examined for 27 species of Geraniales, including 13 species of Pelargonium. Extensive gene and intron losses were detected across the Geraniales with Pelargonium representing the most gene depauperate lineage in the family. Plotting these events on the Geraniaceae phylogenetic tree showed that gene losses occurred multiple times, whereas intron losses more closely reflected the relationships among taxa. In addition, P. australe acquired an intron by horizontal transfer. Comparisons of nucleotide substitution rates in Pelargonium showed that synonymous changes in nuclear genes were much lower than in mitochondrial genes. This is in contrast to the previously published studies that indicated that nuclear genes have 16 fold higher rates than mitochondrial genes across angiosperms. Elevated synonymous substitutions occurred for each mitochondrial gene in Pelargonium with the highest values 783 and 324 times higher than outgroups and other Geraniaceae, respectively. Pelargonium is one of four unrelated genera of angiosperms (Ajuga, Plantago and Silene) that have experienced highly accelerated nucleotide substitutions in mitogenomes. It is distinct from most angiosperms in also having elevated substitution rates in plastid genes but the cause of rate accelerations in Pelargonium plastomes and mitogenomes may be different.
Collapse
Affiliation(s)
- KyoungSu Choi
- Department of Integrative Biology, University of Texas, Austin, TX 78712, USA
| | - Mao-Lun Weng
- Department of Biology, Westfield State University, Westfield, MA, USA
| | - Tracey A Ruhlman
- Department of Integrative Biology, University of Texas, Austin, TX 78712, USA
| | - Robert K Jansen
- Department of Integrative Biology, University of Texas, Austin, TX 78712, USA; Center for Excellence for Bionanoscience Research, King Abdulaziz University (KAU), Jeddah 21589, Saudi Arabia.
| |
Collapse
|
17
|
Nucleotide substitution rates of diatom plastid encoded protein genes are positively correlated with genome architecture. Sci Rep 2020; 10:14358. [PMID: 32873883 PMCID: PMC7462845 DOI: 10.1038/s41598-020-71473-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 08/17/2020] [Indexed: 01/02/2023] Open
Abstract
Diatoms are the largest group of heterokont algae with more than 100,000 species. As one of the single-celled photosynthetic organisms that inhabit marine, aquatic and terrestrial ecosystems, diatoms contribute ~ 45% of global primary production. Despite their ubiquity and environmental significance, very few diatom plastid genomes (plastomes) have been sequenced and studied. This study explored patterns of nucleotide substitution rates of diatom plastids across the entire suite of plastome protein-coding genes for 40 taxa representing the major clades. The highest substitution rate was lineage-specific within the araphid 2 taxon Astrosyne radiata and radial 2 taxon Proboscia sp. Rate heterogeneity was also evident in different functional classes and individual genes. Similar to land plants, proteins genes involved in photosynthetic metabolism have lower synonymous and nonsynonymous substitutions rates than those involved in transcription and translation. Significant positive correlations were identified between substitution rates and measures of genomic rearrangements, including indels and inversions, which is a similar result to what was found in legume plants. This work advances the understanding of the molecular evolution of diatom plastomes and provides a foundation for future studies.
Collapse
|
18
|
Wu Z, Waneka G, Broz AK, King CR, Sloan DB. MSH1 is required for maintenance of the low mutation rates in plant mitochondrial and plastid genomes. Proc Natl Acad Sci U S A 2020. [PMID: 32601224 DOI: 10.1073/pnas.2001998117/suppl_file/pnas.2001998117.sd01.xlsx] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023] Open
Abstract
Mitochondrial and plastid genomes in land plants exhibit some of the slowest rates of sequence evolution observed in any eukaryotic genome, suggesting an exceptional ability to prevent or correct mutations. However, the mechanisms responsible for this extreme fidelity remain unclear. We tested seven candidate genes involved in cytoplasmic DNA replication, recombination, and repair (POLIA, POLIB, MSH1, RECA3, UNG, FPG, and OGG1) for effects on mutation rates in the model angiosperm Arabidopsis thaliana by applying a highly accurate DNA sequencing technique (duplex sequencing) that can detect newly arisen mitochondrial and plastid mutations even at low heteroplasmic frequencies. We find that disrupting MSH1 (but not the other candidate genes) leads to massive increases in the frequency of point mutations and small indels and changes to the mutation spectrum in mitochondrial and plastid DNA. We also used droplet digital PCR to show transmission of de novo heteroplasmies across generations in msh1 mutants, confirming a contribution to heritable mutation rates. This dual-targeted gene is part of an enigmatic lineage within the mutS mismatch repair family that we find is also present outside of green plants in multiple eukaryotic groups (stramenopiles, alveolates, haptophytes, and cryptomonads), as well as certain bacteria and viruses. MSH1 has previously been shown to limit ectopic recombination in plant cytoplasmic genomes. Our results point to a broader role in recognition and correction of errors in plant mitochondrial and plastid DNA sequence, leading to greatly suppressed mutation rates perhaps via initiation of double-stranded breaks and repair pathways based on faithful homologous recombination.
Collapse
Affiliation(s)
- Zhiqiang Wu
- Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, 518120 Shenzhen, China
- Department of Biology, Colorado State University, Fort Collins, CO 80523
| | - Gus Waneka
- Department of Biology, Colorado State University, Fort Collins, CO 80523
| | - Amanda K Broz
- Department of Biology, Colorado State University, Fort Collins, CO 80523
| | - Connor R King
- Department of Biology, Colorado State University, Fort Collins, CO 80523
| | - Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, CO 80523
| |
Collapse
|
19
|
MSH1 is required for maintenance of the low mutation rates in plant mitochondrial and plastid genomes. Proc Natl Acad Sci U S A 2020; 117:16448-16455. [PMID: 32601224 DOI: 10.1073/pnas.2001998117] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Mitochondrial and plastid genomes in land plants exhibit some of the slowest rates of sequence evolution observed in any eukaryotic genome, suggesting an exceptional ability to prevent or correct mutations. However, the mechanisms responsible for this extreme fidelity remain unclear. We tested seven candidate genes involved in cytoplasmic DNA replication, recombination, and repair (POLIA, POLIB, MSH1, RECA3, UNG, FPG, and OGG1) for effects on mutation rates in the model angiosperm Arabidopsis thaliana by applying a highly accurate DNA sequencing technique (duplex sequencing) that can detect newly arisen mitochondrial and plastid mutations even at low heteroplasmic frequencies. We find that disrupting MSH1 (but not the other candidate genes) leads to massive increases in the frequency of point mutations and small indels and changes to the mutation spectrum in mitochondrial and plastid DNA. We also used droplet digital PCR to show transmission of de novo heteroplasmies across generations in msh1 mutants, confirming a contribution to heritable mutation rates. This dual-targeted gene is part of an enigmatic lineage within the mutS mismatch repair family that we find is also present outside of green plants in multiple eukaryotic groups (stramenopiles, alveolates, haptophytes, and cryptomonads), as well as certain bacteria and viruses. MSH1 has previously been shown to limit ectopic recombination in plant cytoplasmic genomes. Our results point to a broader role in recognition and correction of errors in plant mitochondrial and plastid DNA sequence, leading to greatly suppressed mutation rates perhaps via initiation of double-stranded breaks and repair pathways based on faithful homologous recombination.
Collapse
|
20
|
Postel Z, Touzet P. Cytonuclear Genetic Incompatibilities in Plant Speciation. PLANTS 2020; 9:plants9040487. [PMID: 32290056 PMCID: PMC7238192 DOI: 10.3390/plants9040487] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 04/03/2020] [Accepted: 04/07/2020] [Indexed: 12/13/2022]
Abstract
Due to the endosymbiotic origin of organelles, a pattern of coevolution and coadaptation between organellar and nuclear genomes is required for proper cell function. In this review, we focus on the impact of cytonuclear interaction on the reproductive isolation of plant species. We give examples of cases where species exhibit barriers to reproduction which involve plastid-nuclear or mito-nuclear genetic incompatibilities, and describe the evolutionary processes at play. We also discuss potential mechanisms of hybrid fitness recovery such as paternal leakage. Finally, we point out the possible interplay between plant mating systems and cytonuclear coevolution, and its consequence on plant speciation.
Collapse
|
21
|
Choi IS, Ruhlman TA, Jansen RK. Comparative Mitogenome Analysis of the Genus Trifolium Reveals Independent Gene Fission of ccmFn and Intracellular Gene Transfers in Fabaceae. Int J Mol Sci 2020; 21:E1959. [PMID: 32183014 PMCID: PMC7139807 DOI: 10.3390/ijms21061959] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 02/15/2020] [Accepted: 02/17/2020] [Indexed: 01/30/2023] Open
Abstract
The genus Trifolium is the largest of the tribe Trifolieae in the subfamily Papilionoideae (Fabaceae). The paucity of mitochondrial genome (mitogenome) sequences has hindered comparative analyses among the three genomic compartments of the plant cell (nucleus, mitochondrion and plastid). We assembled four mitogenomes from the two subgenera (Chronosemium and Trifolium) of the genus. The four Trifolium mitogenomes were compact (294,911-348,724 bp in length) and contained limited repetitive (6.6-8.6%) DNA. Comparison of organelle repeat content highlighted the distinct evolutionary trajectory of plastid genomes in a subset of Trifolium species. Intracellular gene transfer (IGT) was analyzed among the three genomic compartments revealing functional transfer of mitochondrial rps1 to nuclear genome along with other IGT events. Phylogenetic analysis based on mitochondrial and nuclear rps1 sequences revealed that the functional transfer in Trifolieae was independent from the event that occurred in robinioid clade that includes genus Lotus. A novel, independent fission event of ccmFn in Trifolium was identified, caused by a 59 bp deletion. Fissions of this gene reported previously in land plants were reassessed and compared with Trifolium.
Collapse
Affiliation(s)
- In-Su Choi
- Department of Integrative Biology, University of Texas at Austin, Austin, TX 78712, USA; (T.A.R.); (R.K.J.)
| | - Tracey A. Ruhlman
- Department of Integrative Biology, University of Texas at Austin, Austin, TX 78712, USA; (T.A.R.); (R.K.J.)
| | - Robert K. Jansen
- Department of Integrative Biology, University of Texas at Austin, Austin, TX 78712, USA; (T.A.R.); (R.K.J.)
- Centre of Excellence in Bionanoscience Research, Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| |
Collapse
|
22
|
Tomáška Ľ, Nosek J. Co-evolution in the Jungle: From Leafcutter Ant Colonies to Chromosomal Ends. J Mol Evol 2020; 88:293-318. [PMID: 32157325 DOI: 10.1007/s00239-020-09935-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 02/25/2020] [Indexed: 02/06/2023]
Abstract
Biological entities are multicomponent systems where each part is directly or indirectly dependent on the others. In effect, a change in a single component might have a consequence on the functioning of its partners, thus affecting the fitness of the entire system. In this article, we provide a few examples of such complex biological systems, ranging from ant colonies to a population of amino acids within a single-polypeptide chain. Based on these examples, we discuss one of the central and still challenging questions in biology: how do such multicomponent consortia co-evolve? More specifically, we ask how telomeres, nucleo-protein complexes protecting the integrity of linear DNA chromosomes, originated from the ancestral organisms having circular genomes and thus not dealing with end-replication and end-protection problems. Using the examples of rapidly evolving topologies of mitochondrial genomes in eukaryotic microorganisms, we show what means of co-evolution were employed to accommodate various types of telomere-maintenance mechanisms in mitochondria. We also describe an unprecedented runaway evolution of telomeric repeats in nuclei of ascomycetous yeasts accompanied by co-evolution of telomere-associated proteins. We propose several scenarios derived from research on telomeres and supported by other studies from various fields of biology, while emphasizing that the relevant answers are still not in sight. It is this uncertainty and a lack of a detailed roadmap that makes the journey through the jungle of biological systems still exciting and worth undertaking.
Collapse
Affiliation(s)
- Ľubomír Tomáška
- Department of Genetics, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15, Bratislava, Slovakia.
| | - Jozef Nosek
- Department of Biochemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, 842 15, Bratislava, Slovakia
| |
Collapse
|
23
|
Ding H, Zhu R, Dong J, Bi D, Jiang L, Zeng J, Huang Q, Liu H, Xu W, Wu L, Kan X. Next-Generation Genome Sequencing of Sedum plumbizincicola Sheds Light on the Structural Evolution of Plastid rRNA Operon and Phylogenetic Implications within Saxifragales. PLANTS (BASEL, SWITZERLAND) 2019; 8:E386. [PMID: 31569538 PMCID: PMC6843225 DOI: 10.3390/plants8100386] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 09/27/2019] [Accepted: 09/28/2019] [Indexed: 01/21/2023]
Abstract
The genus Sedum, with about 470 recognized species, is classified in the family Crassulaceae of the order Saxifragales. Phylogenetic relationships within the Saxifragales are still unresolved and controversial. In this study, the plastome of S. plumbizincicola was firstly presented, with a focus on the structural analysis of rrn operon and phylogenetic implications within the order Saxifragaceae. The assembled complete plastome of S. plumbizincicola is 149,397 bp in size, with a typical circular, double-stranded, and quadripartite structure of angiosperms. It contains 133 genes, including 85 protein-coding genes (PCGs), 36 tRNA genes, 8 rRNA genes, and four pseudogenes (one ycf1, one rps19, and two ycf15). The predicted secondary structure of S. plumbizincicola 16S rRNA includes three main domains organized in 74 helices. Further, our results confirm that 4.5S rRNA of higher plants is associated with fragmentation of 23S rRNA progenitor. Notably, we also found the sequence of putative rrn5 promoter has some evolutionary implications within the order Saxifragales. Moreover, our phylogenetic analyses suggested that S. plumbizincicola had a closer relationship with S. sarmentosum than S. oryzifolium, and supported the taxonomic revision of Phedimus. Our findings of the present study will be useful for further investigation of the evolution of plastid rRNA operon and phylogenetic relationships within Saxifragales.
Collapse
Affiliation(s)
- Hengwu Ding
- The Institute of Bioinformatics, College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China.
- The Provincial Key Laboratory of the Conservation and Exploitation Research of Biological Resources in Anhui, Wuhu 241000, Anhui, China.
| | - Ran Zhu
- The Institute of Bioinformatics, College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China.
| | - Jinxiu Dong
- The Institute of Bioinformatics, College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China.
| | - De Bi
- National Engineering Laboratory of Soil Pollution Control and Remediation Technologies, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, Jiangsu, China.
| | - Lan Jiang
- The Institute of Bioinformatics, College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China.
| | - Juhua Zeng
- The Institute of Bioinformatics, College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China.
| | - Qingyu Huang
- The Institute of Bioinformatics, College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China.
| | - Huan Liu
- National Engineering Laboratory of Soil Pollution Control and Remediation Technologies, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, Jiangsu, China.
| | - Wenzhong Xu
- Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
| | - Longhua Wu
- National Engineering Laboratory of Soil Pollution Control and Remediation Technologies, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, Jiangsu, China.
| | - Xianzhao Kan
- The Institute of Bioinformatics, College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China.
- The Provincial Key Laboratory of the Conservation and Exploitation Research of Biological Resources in Anhui, Wuhu 241000, Anhui, China.
| |
Collapse
|
24
|
Barrett CF, Sinn BT, Kennedy AH. Unprecedented Parallel Photosynthetic Losses in a Heterotrophic Orchid Genus. Mol Biol Evol 2019; 36:1884-1901. [PMID: 31058965 PMCID: PMC6736286 DOI: 10.1093/molbev/msz111] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Heterotrophic plants are evolutionary experiments in genomic, morphological, and physiological change. Yet, genomic sampling gaps exist among independently derived heterotrophic lineages, leaving unanswered questions about the process of genome modification. Here, we have sequenced complete plastid genomes for all species of the leafless orchid genus Hexalectris, including multiple individuals for most, and leafy relatives Basiphyllaea and Bletia. Our objectives are to determine the number of independent losses of photosynthesis and to test hypotheses on the process of genome degradation as a result of relaxed selection. We demonstrate four to five independent losses of photosynthesis in Hexalectris based on degradation of the photosynthetic apparatus, with all but two species displaying evidence of losses, and variation in gene loss extending below the species level. Degradation in the atp complex is advanced in Hexalectris warnockii, whereas only minimal degradation (i.e., physical loss) has occurred among some "housekeeping" genes. We find genomic rearrangements, shifts in Inverted Repeat boundaries including complete loss in one accession of H. arizonica, and correlations among substitutional and genomic attributes. Our unprecedented finding of multiple, independent transitions to a fully mycoheterotrophic lifestyle in a single genus reveals that the number of such transitions among land plants is likely underestimated. This study underscores the importance of dense taxon sampling, which is highly informative for advancing models of genome evolution in heterotrophs. Mycoheterotrophs such as Hexalectris provide forward-genetic opportunities to study the consequences of radical genome evolution beyond what is possible with mutational studies in model organisms alone.
Collapse
Affiliation(s)
- Craig F Barrett
- Department of Biology, West Virginia University, Morgantown, WV
| | - Brandon T Sinn
- Department of Biology, West Virginia University, Morgantown, WV
| | - Aaron H Kennedy
- Mycology and Nematology Genetic Diversity and Biology Laboratory, USDA-APHIS, Beltsville, MD
| |
Collapse
|
25
|
Forsythe ES, Sharbrough J, Havird JC, Warren JM, Sloan DB. CyMIRA: The Cytonuclear Molecular Interactions Reference for Arabidopsis. Genome Biol Evol 2019; 11:2194-2202. [PMID: 31282937 PMCID: PMC6685490 DOI: 10.1093/gbe/evz144] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2019] [Indexed: 12/11/2022] Open
Abstract
The function and evolution of eukaryotic cells depend upon direct molecular interactions between gene products encoded in nuclear and cytoplasmic genomes. Understanding how these cytonuclear interactions drive molecular evolution and generate genetic incompatibilities between isolated populations and species is of central importance to eukaryotic biology. Plants are an outstanding system to investigate such effects because of their two different genomic compartments present in the cytoplasm (mitochondria and plastids) and the extensive resources detailing subcellular targeting of nuclear-encoded proteins. However, the field lacks a consistent classification scheme for mitochondrial- and plastid-targeted proteins based on their molecular interactions with cytoplasmic genomes and gene products, which hinders efforts to standardize and compare results across studies. Here, we take advantage of detailed knowledge about the model angiosperm Arabidopsis thaliana to provide a curated database of plant cytonuclear interactions at the molecular level. CyMIRA (Cytonuclear Molecular Interactions Reference for Arabidopsis) is available at http://cymira.colostate.edu/ and https://github.com/dbsloan/cymira and will serve as a resource to aid researchers in partitioning evolutionary genomic data into functional gene classes based on organelle targeting and direct molecular interaction with cytoplasmic genomes and gene products. It includes 11 categories (and 27 subcategories) of different cytonuclear complexes and types of molecular interactions, and it reports residue-level information for cytonuclear contact sites. We hope that this framework will make it easier to standardize, interpret, and compare studies testing the functional and evolutionary consequences of cytonuclear interactions.
Collapse
Affiliation(s)
| | | | - Justin C Havird
- Department of Integrative Biology, University of Texas, Austin
| | | | | |
Collapse
|
26
|
Grisdale CJ, Smith DR, Archibald JM. Relative Mutation Rates in Nucleomorph-Bearing Algae. Genome Biol Evol 2019; 11:1045-1053. [PMID: 30859201 PMCID: PMC6456004 DOI: 10.1093/gbe/evz056] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/08/2019] [Indexed: 12/23/2022] Open
Abstract
Chlorarachniophyte and cryptophyte algae are unique among plastid-containing species in that they have a nucleomorph genome: a compact, highly reduced nuclear genome from a photosynthetic eukaryotic endosymbiont. Despite their independent origins, the nucleomorph genomes of these two lineages have similar genomic architectures, but little is known about the evolutionary pressures impacting nucleomorph DNA, particularly how their rates of evolution compare to those of the neighboring genetic compartments (the mitochondrion, plastid, and nucleus). Here, we use synonymous substitution rates to estimate relative mutation rates in the four genomes of nucleomorph-bearing algae. We show that the relative mutation rates of the host versus endosymbiont nuclear genomes are similar in both chlorarachniophytes and cryptophytes, despite the fact that nucleomorph gene sequences are notoriously highly divergent. There is some evidence, however, for slightly elevated mutation rates in the nucleomorph DNA of chlorarachniophytes-a feature not observed in that of cryptophytes. For both lineages, relative mutation rates in the plastid appear to be lower than those in the nucleus and nucleomorph (and, in one case, the mitochondrion), which is consistent with studies of other plastid-bearing protists. Given the divergent nature of nucleomorph genes, our finding of relatively low evolutionary rates in these genomes suggests that for both lineages a burst of evolutionary change and/or decreased selection pressures likely occurred early in the integration of the secondary endosymbiont.
Collapse
Affiliation(s)
- Cameron J Grisdale
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada.,Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - David R Smith
- Department of Biology, University of Western Ontario, London, Ontario, Canada
| | - John M Archibald
- Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, Nova Scotia, Canada.,Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| |
Collapse
|
27
|
Lencina F, Landau AM, Petterson ME, Pacheco MG, Kobayashi K, Prina AR. The rpl23 gene and pseudogene are hotspots of illegitimate recombination in barley chloroplast mutator seedlings. Sci Rep 2019; 9:9960. [PMID: 31292475 PMCID: PMC6620283 DOI: 10.1038/s41598-019-46321-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 06/26/2019] [Indexed: 11/23/2022] Open
Abstract
Previously, through a TILLING (Targeting Induced Local Lesions in Genomes) approach applied on barley chloroplast mutator (cpm) seedlings a high frequency of polymorphisms in the rpl23 gene was detected. All the polymorphisms corresponded to five differences already known to exist in nature between the rpl23 gene located in the inverted repeats (IRs) and the rpl23 pseudogene located in the large single copy region (LSC). In this investigation, polymorphisms in the rpl23 gene were verified and besides, a similar situation was found for the pseudogene in cpm seedlings. On the other hand, no polymorphisms were found in any of those loci in 40 wild type barley seedlings. Those facts and the independent occurrence of polymorphisms in the gene and pseudogene in individual seedlings suggest that the detected polymorphisms initially arose from gene conversion between gene and pseudogene. Moreover, an additional recombination process involving small recombinant segments seems to occur between the two gene copies as a consequence of their location in the IRs. These and previous results support the hypothesis that the CPM protein is a component of the plastome mismatch repair (MMR) system, whose failure of the anti-recombination activity results in increased illegitimate recombination between the rpl23 gene and pseudogene.
Collapse
Affiliation(s)
- F Lencina
- Instituto de Genética "Ewald A. Favret", CICVyA (Centro de Investigación en Ciencias Veterinarias y Agronómicas), INTA (Instituto Nacional de Tecnología Agropecuaria), Nicolás Repetto y de los Reseros s/n (1686), Hurlingham, Buenos Aires, Argentina
| | - A M Landau
- Instituto de Genética "Ewald A. Favret", CICVyA (Centro de Investigación en Ciencias Veterinarias y Agronómicas), INTA (Instituto Nacional de Tecnología Agropecuaria), Nicolás Repetto y de los Reseros s/n (1686), Hurlingham, Buenos Aires, Argentina
| | - M E Petterson
- Instituto de Genética "Ewald A. Favret", CICVyA (Centro de Investigación en Ciencias Veterinarias y Agronómicas), INTA (Instituto Nacional de Tecnología Agropecuaria), Nicolás Repetto y de los Reseros s/n (1686), Hurlingham, Buenos Aires, Argentina
| | - M G Pacheco
- Instituto de Genética "Ewald A. Favret", CICVyA (Centro de Investigación en Ciencias Veterinarias y Agronómicas), INTA (Instituto Nacional de Tecnología Agropecuaria), Nicolás Repetto y de los Reseros s/n (1686), Hurlingham, Buenos Aires, Argentina
| | - K Kobayashi
- Laboratorio de Agrobiotecnología, Grupo Biología Molecular Vegetal Aplicada, Instituto de Biodiversidad y Biología Experimental y Aplicada (IBBEA, CONICET-UBA), Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, UBA, Buenos Aires, Argentina
| | - A R Prina
- Instituto de Genética "Ewald A. Favret", CICVyA (Centro de Investigación en Ciencias Veterinarias y Agronómicas), INTA (Instituto Nacional de Tecnología Agropecuaria), Nicolás Repetto y de los Reseros s/n (1686), Hurlingham, Buenos Aires, Argentina.
| |
Collapse
|
28
|
Plastid phylogenomic insights into the evolution of Caryophyllales. Mol Phylogenet Evol 2019; 134:74-86. [DOI: 10.1016/j.ympev.2018.12.023] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Revised: 12/17/2018] [Accepted: 12/19/2018] [Indexed: 11/22/2022]
|
29
|
Williams AM, Friso G, van Wijk KJ, Sloan DB. Extreme variation in rates of evolution in the plastid Clp protease complex. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 98:243-259. [PMID: 30570818 DOI: 10.1111/tpj.14208] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 11/29/2018] [Accepted: 12/10/2018] [Indexed: 05/08/2023]
Abstract
Eukaryotic cells represent an intricate collaboration between multiple genomes, even down to the level of multi-subunit complexes in mitochondria and plastids. One such complex in plants is the caseinolytic protease (Clp), which plays an essential role in plastid protein turnover. The proteolytic core of Clp comprises subunits from one plastid-encoded gene (clpP1) and multiple nuclear genes. TheclpP1 gene is highly conserved across most green plants, but it is by far the fastest evolving plastid-encoded gene in some angiosperms. To better understand these extreme and mysterious patterns of divergence, we investigated the history ofclpP1 molecular evolution across green plants by extracting sequences from 988 published plastid genomes. We find thatclpP1 has undergone remarkably frequent bouts of accelerated sequence evolution and architectural changes (e.g. a loss of introns andRNA-editing sites) within seed plants. AlthoughclpP1 is often assumed to be a pseudogene in such cases, multiple lines of evidence suggest that this is rarely true. We applied comparative native gel electrophoresis of chloroplast protein complexes followed by protein mass spectrometry in two species within the angiosperm genusSilene, which has highly elevated and heterogeneous rates ofclpP1 evolution. We confirmed thatclpP1 is expressed as a stable protein and forms oligomeric complexes with the nuclear-encoded Clp subunits, even in one of the most divergentSilene species. Additionally, there is a tight correlation between amino acid substitution rates inclpP1 and the nuclear-encoded Clp subunits across a broad sampling of angiosperms, suggesting continuing selection on interactions within this complex.
Collapse
Affiliation(s)
- Alissa M Williams
- Department of Biology, Graduate Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Giulia Friso
- Section of Plant Biology, School of Integrative Plant Sciences (SIPS), Cornell University, Ithaca, NY, 14853, USA
| | - Klaas J van Wijk
- Section of Plant Biology, School of Integrative Plant Sciences (SIPS), Cornell University, Ithaca, NY, 14853, USA
| | - Daniel B Sloan
- Department of Biology, Graduate Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO, 80523, USA
| |
Collapse
|
30
|
Röschenbleck J, Wicke S, Weinl S, Kudla J, Müller KF. Genus-Wide Screening Reveals Four Distinct Types of Structural Plastid Genome Organization in Pelargonium (Geraniaceae). Genome Biol Evol 2018; 9:64-76. [PMID: 28172771 PMCID: PMC5381562 DOI: 10.1093/gbe/evw271] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/10/2016] [Indexed: 12/22/2022] Open
Abstract
Geraniaceae are known for their unusual plastid genomes (plastomes), with the genus Pelargonium being most conspicuous with regard to plastome size and gene organization as judged by the sequenced plastomes of P. x hortorum and P. alternans. However, the hybrid origin of P. x hortorum and the uncertain phylogenetic position of P. alternans obscure the events that led to these extraordinary plastomes. Here, we examine all plastid reconfiguration hotspots for 60 Pelargonium species across all subgenera using a PCR and sequencing approach. Our reconstruction of the rearrangement history revealed four distinct plastome types. The ancestral plastome configuration in the two subgenera Magnipetala and Pelargonium is consistent with that of the P. alternans plastome, whereas that of the subgenus Parvulipetala deviates from this organization by one synapomorphic inversion in the trnNGUU–ndhF region. The plastome of P. x hortorum resembles those of one group of the subgenus Paucisignata, but differs from a second group by another inversion in the psaI–psaJ region. The number of microstructural changes and amount of repetitive DNA are generally elevated in all inverted regions. Nucleotide substitution rates correlate positively with the number of indels in all regions across the different subgenera. We also observed lineage- and species-specific changes in the gene content, including gene duplications and fragmentations. For example, the plastid rbcL–psaI region of Pelargonium contains a highly variable accD-like region. Our results suggest alternative evolutionary paths under possibly changing modes of plastid transmission and indicate the non-functionalization of the plastid accD gene in Pelargonium.
Collapse
Affiliation(s)
- Joachim Röschenbleck
- Institute for Evolution and Biodiversity, University of Muenster, Muenster, Germany
- Institute for Plant Biology and Biotechnology, University of Muenster, Muenster, Germany
| | - Susann Wicke
- Institute for Evolution and Biodiversity, University of Muenster, Muenster, Germany
- Corresponding author: E-mail:
| | - Stefan Weinl
- Institute for Plant Biology and Biotechnology, University of Muenster, Muenster, Germany
| | - Jörg Kudla
- Institute for Plant Biology and Biotechnology, University of Muenster, Muenster, Germany
| | - Kai F. Müller
- Institute for Evolution and Biodiversity, University of Muenster, Muenster, Germany
| |
Collapse
|
31
|
Sinn BT, Sedmak DD, Kelly LM, Freudenstein JV. Total duplication of the small single copy region in the angiosperm plastome: Rearrangement and inverted repeat instability in Asarum. AMERICAN JOURNAL OF BOTANY 2018; 105:71-84. [PMID: 29532923 DOI: 10.1002/ajb2.1001] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 11/27/2017] [Indexed: 05/21/2023]
Abstract
PREMISE OF THE STUDY As more plastomes are assembled, it is evident that rearrangements, losses, intergenic spacer expansion and contraction, and syntenic breaks within otherwise functioning plastids are more common than was thought previously, and such changes have developed independently in disparate lineages. However, to date, the magnoliids remain characterized by their highly conserved plastid genomes (plastomes). METHODS Illumina HiSeq and MiSeq platforms were used to sequence the plastomes of Saruma henryi and those of representative species from each of the six taxonomic sections of Asarum. Sequenced plastomes were compared in a phylogenetic context provided by maximum likelihood and parsimony inferences made using an additional 18 publicly available plastomes from early-diverging angiosperm lineages. KEY RESULTS In contrast to previously published magnoliid plastomes and the newly sequenced Saruma henryi plastome published here, Asarum plastomes have undergone extensive disruption and contain extremely lengthy AT-repeat regions. The entirety of the small single copy region (SSC) of A. canadense and A. sieboldii var. sieboldii has been incorporated into the inverted repeat regions (IR), and the SSC of A. delavayi is only 14 bp long. All sampled Asarum plastomes share an inversion of a large portion of the large single copy region (LSC) such that trnE-UUC is adjacent to the LSC-IR boundary. CONCLUSIONS Plastome divergence in Asarum appears to be consistent with trends seen in highly rearranged plastomes of the monocots and eudicots. We propose that plastome instability in Asarum is due to repetitive motifs that serve as recombinatory substrates and reduce genome stability.
Collapse
Affiliation(s)
- Brandon T Sinn
- The Ohio State University Museum of Biological Diversity, Department of Evolution, Ecology, and Organismal Biology, Columbus, Ohio 43212, USA
- West Virginia University, Department of Biology, Morgantown, West Virginia 26505, USA
| | - Dylan D Sedmak
- The Ohio State University Museum of Biological Diversity, Department of Evolution, Ecology, and Organismal Biology, Columbus, Ohio 43212, USA
| | | | - John V Freudenstein
- The Ohio State University Museum of Biological Diversity, Department of Evolution, Ecology, and Organismal Biology, Columbus, Ohio 43212, USA
| |
Collapse
|
32
|
Park S, Ruhlman TA, Weng ML, Hajrah NH, Sabir JS, Jansen RK. Contrasting Patterns of Nucleotide Substitution Rates Provide Insight into Dynamic Evolution of Plastid and Mitochondrial Genomes of Geranium. Genome Biol Evol 2017; 9:1766-1780. [PMID: 28854633 PMCID: PMC5570028 DOI: 10.1093/gbe/evx124] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/03/2017] [Indexed: 12/25/2022] Open
Abstract
Geraniaceae have emerged as a model system for investigating the causes and consequences of variation in plastid and mitochondrial genomes. Incredible structural variation in plastid genomes (plastomes) and highly accelerated evolutionary rates have been reported in selected lineages and functional groups of genes in both plastomes and mitochondrial genomes (mitogenomes), and these phenomena have been implicated in cytonuclear incompatibility. Previous organelle genome studies have included limited sampling of Geranium, the largest genus in the family with over 400 species. This study reports on rates and patterns of nucleotide substitutions in plastomes and mitogenomes of 17 species of Geranium and representatives of other Geraniaceae. As detected across other angiosperms, substitution rates in the plastome are 3.5 times higher than the mitogenome in most Geranium. However, in the branch leading to Geranium brycei/Geranium incanum mitochondrial genes experienced significantly higher dN and dS than plastid genes, a pattern that has only been detected in one other angiosperm. Furthermore, rate accelerations differ in the two organelle genomes with plastomes having increased dN and mitogenomes with increased dS. In the Geranium phaeum/Geranium reflexum clade, duplicate copies of clpP and rpoA genes that experienced asymmetric rate divergence were detected in the single copy region of the plastome. In the case of rpoA, the branch leading to G. phaeum/G. reflexum experienced positive selection or relaxation of purifying selection. Finally, the evolution of acetyl-CoA carboxylase is unusual in Geraniaceae because it is only the second angiosperm family where both prokaryotic and eukaryotic ACCases functionally coexist in the plastid.
Collapse
Affiliation(s)
- Seongjun Park
- Department of Integrative Biology, University of Texas at Austin
| | | | - Mao-Lun Weng
- Department of Integrative Biology, University of Texas at Austin
- Department of Biology and Microbiology, South Dakota State University
| | - Nahid H. Hajrah
- Genomic and Biotechnology Research Group, Department of Biological Science, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Jamal S.M. Sabir
- Genomic and Biotechnology Research Group, Department of Biological Science, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Robert K. Jansen
- Department of Integrative Biology, University of Texas at Austin
- Genomic and Biotechnology Research Group, Department of Biological Science, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia
| |
Collapse
|
33
|
Plastome-Wide Nucleotide Substitution Rates Reveal Accelerated Rates in Papilionoideae and Correlations with Genome Features Across Legume Subfamilies. J Mol Evol 2017; 84:187-203. [PMID: 28397003 DOI: 10.1007/s00239-017-9792-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 04/03/2017] [Indexed: 01/08/2023]
Abstract
This study represents the most comprehensive plastome-wide comparison of nucleotide substitution rates across the three subfamilies of Fabaceae: Caesalpinioideae, Mimosoideae, and Papilionoideae. Caesalpinioid and mimosoid legumes have large, unrearranged plastomes compared with papilionoids, which exhibit varying levels of rearrangement including the loss of the inverted repeat (IR) in the IR-lacking clade (IRLC). Using 71 genes common to 39 legume taxa representing all the three subfamilies, we show that papilionoids consistently have higher nucleotide substitution rates than caesalpinioids and mimosoids, and rates in the IRLC papilionoids are generally higher than those in the IR-containing papilionoids. Unsurprisingly, this pattern was significantly correlated with growth habit as most papilionoids are herbaceous, whereas caesalpinioids and mimosoids are largely woody. Both nonsynonymous (dN) and synonymous (dS) substitution rates were also correlated with several biological features including plastome size and plastomic rearrangements such as the number of inversions and indels. In agreement with previous reports, we found that genes in the IR exhibit between three and fourfold reductions in the substitution rates relative to genes within the large single-copy or small single-copy regions. Furthermore, former IR genes in IR-lacking taxa exhibit accelerated rates compared with genes contained in the IR.
Collapse
|
34
|
Ruhlman TA, Zhang J, Blazier JC, Sabir JSM, Jansen RK. Recombination-dependent replication and gene conversion homogenize repeat sequences and diversify plastid genome structure. AMERICAN JOURNAL OF BOTANY 2017; 104:559-572. [PMID: 28400415 DOI: 10.3732/ajb.1600453] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 02/23/2017] [Indexed: 05/21/2023]
Abstract
PREMISE OF THE STUDY There is a misinterpretation in the literature regarding the variable orientation of the small single copy region of plastid genomes (plastomes). The common phenomenon of small and large single copy inversion, hypothesized to occur through intramolecular recombination between inverted repeats (IR) in a circular, single unit-genome, in fact, more likely occurs through recombination-dependent replication (RDR) of linear plastome templates. If RDR can be primed through both intra- and intermolecular recombination, then this mechanism could not only create inversion isomers of so-called single copy regions, but also an array of alternative sequence arrangements. METHODS We used Illumina paired-end and PacBio single-molecule real-time (SMRT) sequences to characterize repeat structure in the plastome of Monsonia emarginata (Geraniaceae). We used OrgConv and inspected nucleotide alignments to infer ancestral nucleotides and identify gene conversion among repeats and mapped long (>1 kb) SMRT reads against the unit-genome assembly to identify alternative sequence arrangements. RESULTS Although M. emarginata lacks the canonical IR, we found that large repeats (>1 kilobase; kb) represent ∼22% of the plastome nucleotide content. Among the largest repeats (>2 kb), we identified GC-biased gene conversion and mapping filtered, long SMRT reads to the M. emarginata unit-genome assembly revealed alternative, substoichiometric sequence arrangements. CONCLUSION We offer a model based on RDR and gene conversion between long repeated sequences in the M. emarginata plastome and provide support that both intra-and intermolecular recombination between large repeats, particularly in repeat-rich plastomes, varies unit-genome structure while homogenizing the nucleotide sequence of repeats.
Collapse
Affiliation(s)
- Tracey A Ruhlman
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas 78712 USA
| | - Jin Zhang
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas 78712 USA
| | - John C Blazier
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas 78712 USA
| | - Jamal S M Sabir
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589 Saudi Arabia
| | - Robert K Jansen
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas 78712 USA
- Biotechnology Research Group, Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589 Saudi Arabia
| |
Collapse
|
35
|
Weng ML, Ruhlman TA, Jansen RK. Expansion of inverted repeat does not decrease substitution rates in Pelargonium plastid genomes. THE NEW PHYTOLOGIST 2017; 214:842-851. [PMID: 27991660 DOI: 10.1111/nph.14375] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 11/04/2016] [Indexed: 05/23/2023]
Abstract
For species with minor inverted repeat (IR) boundary changes in the plastid genome (plastome), nucleotide substitution rates were previously shown to be lower in the IR than the single copy regions (SC). However, the impact of large-scale IR expansion/contraction on plastid nucleotide substitution rates among closely related species remains unclear. We included plastomes from 22 Pelargonium species, including eight newly sequenced genomes, and used both pairwise and model-based comparisons to investigate the impact of the IR on sequence evolution in plastids. Ten types of plastome organization with different inversions or IR boundary changes were identified in Pelargonium. Inclusion in the IR was not sufficient to explain the variation of nucleotide substitution rates. Instead, the rate heterogeneity in Pelargonium plastomes was a mixture of locus-specific, lineage-specific and IR-dependent effects. Our study of Pelargonium plastomes that vary in IR length and gene content demonstrates that the evolutionary consequences of retaining these repeats are more complicated than previously suggested.
Collapse
Affiliation(s)
- Mao-Lun Weng
- Department of Biology and Microbiology, South Dakota State University, Brookings, SD, 57006, USA
| | - Tracey A Ruhlman
- Department of Integrative Biology, University of Texas, Austin, TX, 78712, USA
| | - Robert K Jansen
- Department of Integrative Biology, University of Texas, Austin, TX, 78712, USA
- Department of Biological Sciences, Biotechnology Research Group, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| |
Collapse
|
36
|
Sloan DB, Havird JC, Sharbrough J. The on-again, off-again relationship between mitochondrial genomes and species boundaries. Mol Ecol 2017; 26:2212-2236. [PMID: 27997046 PMCID: PMC6534505 DOI: 10.1111/mec.13959] [Citation(s) in RCA: 145] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Revised: 11/16/2016] [Accepted: 11/18/2016] [Indexed: 12/12/2022]
Abstract
The study of reproductive isolation and species barriers frequently focuses on mitochondrial genomes and has produced two alternative and almost diametrically opposed narratives. On one hand, mtDNA may be at the forefront of speciation events, with co-evolved mitonuclear interactions responsible for some of the earliest genetic incompatibilities arising among isolated populations. On the other hand, there are numerous cases of introgression of mtDNA across species boundaries even when nuclear gene flow is restricted. We argue that these seemingly contradictory patterns can result from a single underlying cause. Specifically, the accumulation of deleterious mutations in mtDNA creates a problem with two alternative evolutionary solutions. In some cases, compensatory or epistatic changes in the nuclear genome may ameliorate the effects of mitochondrial mutations, thereby establishing coadapted mitonuclear genotypes within populations and forming the basis of reproductive incompatibilities between populations. Alternatively, populations with high mitochondrial mutation loads may be rescued by replacement with a more fit, foreign mitochondrial haplotype. Coupled with many nonadaptive mechanisms of introgression that can preferentially affect cytoplasmic genomes, this form of adaptive introgression may contribute to the widespread discordance between mitochondrial and nuclear genealogies. Here, we review recent advances related to mitochondrial introgression and mitonuclear incompatibilities, including the potential for cointrogression of mtDNA and interacting nuclear genes. We also address an emerging controversy over the classic assumption that selection on mitochondrial genomes is inefficient and discuss the mechanisms that lead lineages down alternative evolutionary paths in response to mitochondrial mutation accumulation.
Collapse
Affiliation(s)
- Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Justin C Havird
- Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA
| | - Joel Sharbrough
- Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA
| |
Collapse
|
37
|
Positive Selection in Rapidly Evolving Plastid-Nuclear Enzyme Complexes. Genetics 2016; 204:1507-1522. [PMID: 27707788 DOI: 10.1534/genetics.116.188268] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 10/04/2016] [Indexed: 11/18/2022] Open
Abstract
Rates of sequence evolution in plastid genomes are generally low, but numerous angiosperm lineages exhibit accelerated evolutionary rates in similar subsets of plastid genes. These genes include clpP1 and accD, which encode components of the caseinolytic protease (CLP) and acetyl-coA carboxylase (ACCase) complexes, respectively. Whether these extreme and repeated accelerations in rates of plastid genome evolution result from adaptive change in proteins (i.e., positive selection) or simply a loss of functional constraint (i.e., relaxed purifying selection) is a source of ongoing controversy. To address this, we have taken advantage of the multiple independent accelerations that have occurred within the genus Silene (Caryophyllaceae) by examining phylogenetic and population genetic variation in the nuclear genes that encode subunits of the CLP and ACCase complexes. We found that, in species with accelerated plastid genome evolution, the nuclear-encoded subunits in the CLP and ACCase complexes are also evolving rapidly, especially those involved in direct physical interactions with plastid-encoded proteins. A massive excess of nonsynonymous substitutions between species relative to levels of intraspecific polymorphism indicated a history of strong positive selection (particularly in CLP genes). Interestingly, however, some species are likely undergoing loss of the native (heteromeric) plastid ACCase and putative functional replacement by a duplicated cytosolic (homomeric) ACCase. Overall, the patterns of molecular evolution in these plastid-nuclear complexes are unusual for anciently conserved enzymes. They instead resemble cases of antagonistic coevolution between pathogens and host immune genes. We discuss a possible role of plastid-nuclear conflict as a novel cause of accelerated evolution.
Collapse
|
38
|
Lee J, Cho CH, Park SI, Choi JW, Song HS, West JA, Bhattacharya D, Yoon HS. Parallel evolution of highly conserved plastid genome architecture in red seaweeds and seed plants. BMC Biol 2016; 14:75. [PMID: 27589960 PMCID: PMC5010701 DOI: 10.1186/s12915-016-0299-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 08/17/2016] [Indexed: 11/10/2022] Open
Abstract
Background The red algae (Rhodophyta) diverged from the green algae and plants (Viridiplantae) over one billion years ago within the kingdom Archaeplastida. These photosynthetic lineages provide an ideal model to study plastid genome reduction in deep time. To this end, we assembled a large dataset of the plastid genomes that were available, including 48 from the red algae (17 complete and three partial genomes produced for this analysis) to elucidate the evolutionary history of these organelles. Results We found extreme conservation of plastid genome architecture in the major lineages of the multicellular Florideophyceae red algae. Only three minor structural types were detected in this group, which are explained by recombination events of the duplicated rDNA operons. A similar high level of structural conservation (although with different gene content) was found in seed plants. Three major plastid genome architectures were identified in representatives of 46 orders of angiosperms and three orders of gymnosperms. Conclusions Our results provide a comprehensive account of plastid gene loss and rearrangement events involving genome architecture within Archaeplastida and lead to one over-arching conclusion: from an ancestral pool of highly rearranged plastid genomes in red and green algae, the aquatic (Florideophyceae) and terrestrial (seed plants) multicellular lineages display high conservation in plastid genome architecture. This phenomenon correlates with, and could be explained by, the independent and widely divergent (separated by >400 million years) origins of complex sexual cycles and reproductive structures that led to the rapid diversification of these lineages. Electronic supplementary material The online version of this article (doi:10.1186/s12915-016-0299-5) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- JunMo Lee
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Chung Hyun Cho
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Seung In Park
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Ji Won Choi
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Hyun Suk Song
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - John A West
- School of Biosciences 2, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Debashish Bhattacharya
- Department of Ecology, Evolution and Natural Resources, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Hwan Su Yoon
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 16419, Republic of Korea.
| |
Collapse
|
39
|
Logacheva MD, Schelkunov MI, Shtratnikova VY, Matveeva MV, Penin AA. Comparative analysis of plastid genomes of non-photosynthetic Ericaceae and their photosynthetic relatives. Sci Rep 2016; 6:30042. [PMID: 27452401 PMCID: PMC4958920 DOI: 10.1038/srep30042] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 06/27/2016] [Indexed: 12/24/2022] Open
Abstract
Although plastid genomes of flowering plants are typically highly conserved regarding their size, gene content and order, there are some exceptions. Ericaceae, a large and diverse family of flowering plants, warrants special attention within the context of plastid genome evolution because it includes both non-photosynthetic and photosynthetic species with rearranged plastomes and putative losses of "essential" genes. We characterized plastid genomes of three species of Ericaceae, non-photosynthetic Monotropa uniflora and Hypopitys monotropa and photosynthetic Pyrola rotundifolia, using high-throughput sequencing. As expected for non-photosynthetic plants, M. uniflora and H. monotropa have small plastid genomes (46 kb and 35 kb, respectively) lacking genes related to photosynthesis, whereas P. rotundifolia has a larger genome (169 kb) with a gene set similar to other photosynthetic plants. The examined genomes contain an unusually high number of repeats and translocations. Comparative analysis of the expanded set of Ericaceae plastomes suggests that the genes clpP and accD that are present in the plastid genomes of almost all plants have not been lost in this family (as was previously thought) but rather persist in these genomes in unusual forms. Also we found a new gene in P. rotundifolia that emerged as a result of duplication of rps4 gene.
Collapse
Affiliation(s)
- Maria D. Logacheva
- Lomonosov Moscow State University, A.N Belozersky Institute of Physico-Chemical Biology, Moscow, Russia
- Kazan Federal University, Institute of Fundamental Biology and Medicine, Kazan, Russia
| | - Mikhail I. Schelkunov
- Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russia
| | - Victoria Y. Shtratnikova
- Lomonosov Moscow State University, Department of Bioengineering and Bioinformatics, Moscow, Russia
| | - Maria V. Matveeva
- Kazan Federal University, Institute of Fundamental Biology and Medicine, Kazan, Russia
| | - Aleksey A. Penin
- Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russia
- Lomonosov Moscow State University, Department of Genetics, Moscow, Russia
| |
Collapse
|
40
|
Weng ML, Ruhlman TA, Jansen RK. Plastid-Nuclear Interaction and Accelerated Coevolution in Plastid Ribosomal Genes in Geraniaceae. Genome Biol Evol 2016; 8:1824-38. [PMID: 27190001 PMCID: PMC4943186 DOI: 10.1093/gbe/evw115] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Plastids and mitochondria have many protein complexes that include subunits encoded by organelle and nuclear genomes. In animal cells, compensatory evolution between mitochondrial and nuclear-encoded subunits was identified and the high mitochondrial mutation rates were hypothesized to drive compensatory evolution in nuclear genomes. In plant cells, compensatory evolution between plastid and nucleus has rarely been investigated in a phylogenetic framework. To investigate plastid–nuclear coevolution, we focused on plastid ribosomal protein genes that are encoded by plastid and nuclear genomes from 27 Geraniales species. Substitution rates were compared for five sets of genes representing plastid- and nuclear-encoded ribosomal subunit proteins targeted to the cytosol or the plastid as well as nonribosomal protein controls. We found that nonsynonymous substitution rates (dN) and the ratios of nonsynonymous to synonymous substitution rates (ω) were accelerated in both plastid- (CpRP) and nuclear-encoded subunits (NuCpRP) of the plastid ribosome relative to control sequences. Our analyses revealed strong signals of cytonuclear coevolution between plastid- and nuclear-encoded subunits, in which nonsynonymous substitutions in CpRP and NuCpRP tend to occur along the same branches in the Geraniaceae phylogeny. This coevolution pattern cannot be explained by physical interaction between amino acid residues. The forces driving accelerated coevolution varied with cellular compartment of the sequence. Increased ω in CpRP was mainly due to intensified positive selection whereas increased ω in NuCpRP was caused by relaxed purifying selection. In addition, the many indels identified in plastid rRNA genes in Geraniaceae may have contributed to changes in plastid subunits.
Collapse
Affiliation(s)
- Mao-Lun Weng
- Department of Biology, University of Maryland, College Park Department of Integrative Biology, University of Texas, Austin
| | | | - Robert K Jansen
- Department of Integrative Biology, University of Texas, Austin Department of Biological Sciences, Biotechnology Research Group, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia
| |
Collapse
|
41
|
Lim GS, Barrett CF, Pang CC, Davis JI. Drastic reduction of plastome size in the mycoheterotrophic Thismia tentaculata relative to that of its autotrophic relative Tacca chantrieri. AMERICAN JOURNAL OF BOTANY 2016; 103:1129-37. [PMID: 27335389 DOI: 10.3732/ajb.1600042] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 05/06/2016] [Indexed: 05/23/2023]
Abstract
PREMISE OF THE STUDY Heterotrophic angiosperms tend to have reduced plastome sizes relative to those of their autotrophic relatives because genes that code for proteins involved in photosynthesis are lost. However, some plastid-encoded proteins may have vital nonphotosynthetic functions, and the plastome therefore may be retained after the loss of photosynthesis. METHODS We sequenced the plastome of the mycoheterotrophic species Thismia tentaculata and a representative of its sister genus, Tacca chantrieri, using next-generation technology, and we compared sequences and structures of genes and genomes of these species. KEY RESULTS The plastome of Tacca chantrieri is similar to those of other autotrophic taxa of Dioscoreaceae, except in a few local rearrangements and one gene loss. The plastome of Thismia tentaculata is ca. 16 kbp long with a quadripartite structure and is among the smallest known plastomes. Synteny is minimal between the plastomes of Tacca chantrieri and Thismia tentaculata. The latter includes only 12 candidate genes, with all except accD involved in protein synthesis. Of the 12 genes, trnE, trnfM, and accD are frequently among the few that remain in depauperate plastomes. CONCLUSIONS The plastome of Thismia tentaculata, like those of most other heterotrophic plants, includes a small number of genes previously suggested to be essential to plastome survival.
Collapse
Affiliation(s)
- Gwynne S Lim
- The New York Botanical Garden, Pfizer Plant Research Laboratory, 2900 Southern Boulevard, Bronx, New York 10458 USA L. H. Bailey Hortorium, Section of Plant Biology, 412 Mann Library Building, Cornell University, Ithaca, New York 14853 USA
| | - Craig F Barrett
- Department of Biology, Life Sciences Building, PO Box 6057, Morgantown, West Virginia 26506 USA
| | - Chun-Chiu Pang
- School of Biological Sciences, Kadoorie Biological Sciences Building, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Jerrold I Davis
- L. H. Bailey Hortorium, Section of Plant Biology, 412 Mann Library Building, Cornell University, Ithaca, New York 14853 USA
| |
Collapse
|
42
|
Blazier JC, Jansen RK, Mower JP, Govindu M, Zhang J, Weng ML, Ruhlman TA. Variable presence of the inverted repeat and plastome stability in Erodium. ANNALS OF BOTANY 2016; 117:1209-20. [PMID: 27192713 PMCID: PMC4904181 DOI: 10.1093/aob/mcw065] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 01/05/2016] [Accepted: 02/22/2016] [Indexed: 05/18/2023]
Abstract
BACKGROUND AND AIMS Several unrelated lineages such as plastids, viruses and plasmids, have converged on quadripartite genomes of similar size with large and small single copy regions and a large inverted repeat (IR). Except for Erodium (Geraniaceae), saguaro cactus and some legumes, the plastomes of all photosynthetic angiosperms display this structure. The functional significance of the IR is not understood and Erodium provides a system to examine the role of the IR in the long-term stability of these genomes. We compared the degree of genomic rearrangement in plastomes of Erodium that differ in the presence and absence of the IR. METHODS We sequenced 17 new Erodium plastomes. Using 454, Illumina, PacBio and Sanger sequences, 16 genomes were assembled and categorized along with one incomplete and two previously published Erodium plastomes. We conducted phylogenetic analyses among these species using a dataset of 19 protein-coding genes and determined if significantly higher evolutionary rates had caused the long branch seen previously in phylogenetic reconstructions within the genus. Bioinformatic comparisons were also performed to evaluate plastome evolution across the genus. KEY RESULTS Erodium plastomes fell into four types (Type 1-4) that differ in their substitution rates, short dispersed repeat content and degree of genomic rearrangement, gene and intron content and GC content. Type 4 plastomes had significantly higher rates of synonymous substitutions (dS) for all genes and for 14 of the 19 genes non-synonymous substitutions (dN) were significantly accelerated. We evaluated the evidence for a single IR loss in Erodium and in doing so discovered that Type 4 plastomes contain a novel IR. CONCLUSIONS The presence or absence of the IR does not affect plastome stability in Erodium. Rather, the overall repeat content shows a negative correlation with genome stability, a pattern in agreement with other angiosperm groups and recent findings on genome stability in bacterial endosymbionts.
Collapse
Affiliation(s)
- John C Blazier
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - Robert K Jansen
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA Department of Biological Science, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Jeffrey P Mower
- Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Madhu Govindu
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - Jin Zhang
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - Mao-Lun Weng
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - Tracey A Ruhlman
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| |
Collapse
|
43
|
Lemieux C, Otis C, Turmel M. Comparative Chloroplast Genome Analyses of Streptophyte Green Algae Uncover Major Structural Alterations in the Klebsormidiophyceae, Coleochaetophyceae and Zygnematophyceae. FRONTIERS IN PLANT SCIENCE 2016; 7:697. [PMID: 27252715 PMCID: PMC4877394 DOI: 10.3389/fpls.2016.00697] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 05/06/2016] [Indexed: 05/18/2023]
Abstract
The Streptophyta comprises all land plants and six main lineages of freshwater green algae: Mesostigmatophyceae, Chlorokybophyceae, Klebsormidiophyceae, Charophyceae, Coleochaetophyceae and Zygnematophyceae. Previous comparisons of the chloroplast genome from nine streptophyte algae (including four zygnematophyceans) revealed that, although land plant chloroplast DNAs (cpDNAs) inherited most of their highly conserved structural features from green algal ancestors, considerable cpDNA changes took place during the evolution of the Zygnematophyceae, the sister group of land plants. To gain deeper insights into the evolutionary dynamics of the chloroplast genome in streptophyte algae, we sequenced the cpDNAs of nine additional taxa: two klebsormidiophyceans (Entransia fimbriata and Klebsormidium sp. SAG 51.86), one coleocheatophycean (Coleochaete scutata) and six zygnematophyceans (Cylindrocystis brebissonii, Netrium digitus, Roya obtusa, Spirogyra maxima, Cosmarium botrytis and Closterium baillyanum). Our comparative analyses of these genomes with their streptophyte algal counterparts indicate that the large inverted repeat (IR) encoding the rDNA operon experienced loss or expansion/contraction in all three sampled classes and that genes were extensively shuffled in both the Klebsormidiophyceae and Zygnematophyceae. The klebsormidiophycean genomes boast greatly expanded IRs, with the Entransia 60,590-bp IR being the largest known among green algae. The 206,025-bp Entransia cpDNA, which is one of the largest genome among streptophytes, encodes 118 standard genes, i.e., four additional genes compared to its Klebsormidium flaccidum homolog. We inferred that seven of the 21 group II introns usually found in land plants were already present in the common ancestor of the Klebsormidiophyceae and its sister lineages. At 107,236 bp and with 117 standard genes, the Coleochaete IR-less genome is both the smallest and most compact among the streptophyte algal cpDNAs analyzed thus far; it lacks eight genes relative to its Chaetosphaeridium globosum homolog, four of which represent unique events in the evolutionary scenario of gene losses we reconstructed for streptophyte algae. The 10 compared zygnematophycean cpDNAs display tremendous variations at all levels, except gene content. During zygnematophycean evolution, the IR disappeared a minimum of five times, the rDNA operon was broken at four distinct sites, group II introns were lost on at least 43 occasions, and putative foreign genes, mainly of phage/viral origin, were gained.
Collapse
Affiliation(s)
- Claude Lemieux
- Institut de Biologie Intégrative et des Systèmes, Département de Biochimie, de Microbiologie et de Bio-informatique, Université Laval, QuébecQC, Canada
| | | | | |
Collapse
|