1
|
Zwonitzer KD, Tressel LG, Wu Z, Kan S, Broz AK, Mower JP, Ruhlman TA, Jansen RK, Sloan DB, Havird JC. Genome copy number predicts extreme evolutionary rate variation in plant mitochondrial DNA. Proc Natl Acad Sci U S A 2024; 121:e2317240121. [PMID: 38427600 DOI: 10.1073/pnas.2317240121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 01/22/2024] [Indexed: 03/03/2024] Open
Abstract
Nuclear and organellar genomes can evolve at vastly different rates despite occupying the same cell. In most bilaterian animals, mitochondrial DNA (mtDNA) evolves faster than nuclear DNA, whereas this trend is generally reversed in plants. However, in some exceptional angiosperm clades, mtDNA substitution rates have increased up to 5,000-fold compared with closely related lineages. The mechanisms responsible for this acceleration are generally unknown. Because plants rely on homologous recombination to repair mtDNA damage, we hypothesized that mtDNA copy numbers may predict evolutionary rates, as lower copy numbers may provide fewer templates for such repair mechanisms. In support of this hypothesis, we found that copy number explains 47% of the variation in synonymous substitution rates of mtDNA across 60 diverse seed plant species representing ~300 million years of evolution. Copy number was also negatively correlated with mitogenome size, which may be a cause or consequence of mutation rate variation. Both relationships were unique to mtDNA and not observed in plastid DNA. These results suggest that homologous recombinational repair plays a role in driving mtDNA substitution rates in plants and may explain variation in mtDNA evolution more broadly across eukaryotes. Our findings also contribute to broader questions about the relationships between mutation rates, genome size, selection efficiency, and the drift-barrier hypothesis.
Collapse
Affiliation(s)
- Kendra D Zwonitzer
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX 78712
| | - Lydia G Tressel
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX 78712
| | - Zhiqiang Wu
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518000, China
| | - Shenglong Kan
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518000, China
- Marine College, Shandong University, Weihai 264209, China
| | - Amanda K Broz
- Department of Biology, Colorado State University, Fort Collins, CO 80523
| | - Jeffrey P Mower
- Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE 68588
| | - Tracey A Ruhlman
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX 78712
| | - Robert K Jansen
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX 78712
| | - Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, CO 80523
| | - Justin C Havird
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX 78712
| |
Collapse
|
2
|
Lee C, Ruhlman TA, Jansen RK. Rate accelerations in plastid and mitochondrial genomes of Cyperaceae occur in the same clades. Mol Phylogenet Evol 2023; 182:107760. [PMID: 36921696 DOI: 10.1016/j.ympev.2023.107760] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 01/28/2023] [Accepted: 03/08/2023] [Indexed: 03/14/2023]
Abstract
Cyperaceae, the second largest family in the monocot order Poales, comprises >5500 species and includes the genus Eleocharis with ∼ 250 species. A previous study of complete plastomes of two Eleocharis species documented extensive structural heteroplasmy, gene order changes, high frequency of dispersed repeats along with gene losses and duplications. To better understand the phylogenetic distribution of gene and intron content as well as rates and patterns of sequence evolution within and between mitochondrial and plastid genomes of Eleocharis and Cyperaceae, an additional 29 Eleocharis organelle genomes were sequenced and analyzed. Eleocharis experienced extensive gene loss in both genomes while loss of introns was mitochondria-specific. Eleocharis has higher rates of synonymous (dS) and nonsynonymous (dN) substitutions in the plastid and mitochondrion than most sampled angiosperms, and the pattern was distinct from other eudicot lineages with accelerated rates. Several clades showed higher dS and dN in mitochondrial genes than in plastid genes. Furthermore, nucleotide substitution rates of mitochondrial genes were significantly accelerated on the branch leading to Cyperaceae compared to most angiosperms. Mitochondrial genes of Cyperaceae exhibited dramatic loss of RNA editing sites and a negative correlation between RNA editing and dS values was detected among angiosperms. Mutagenic retroprocessing and dysfunction of DNA replication, repair and recombination genes are the most likely cause of striking rate accelerations and loss of edit sites and introns in Eleocharis and Cyperaceae organelle genomes.
Collapse
Affiliation(s)
- Chaehee Lee
- Department of Integrative Biology, University of Texas at Austin, Austin, TX 78712, USA; Department of Plant Sciences, University of California, Davis, Davis, CA 95616, USA.
| | - Tracey A Ruhlman
- Department of Integrative Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Robert K Jansen
- Department of Integrative Biology, University of Texas at Austin, Austin, TX 78712, USA
| |
Collapse
|
3
|
Maternal Donor and Genetic Variation of Lagerstroemia indica Cultivars. Int J Mol Sci 2023; 24:ijms24043606. [PMID: 36835020 PMCID: PMC9964644 DOI: 10.3390/ijms24043606] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/30/2022] [Accepted: 02/08/2023] [Indexed: 02/16/2023] Open
Abstract
Lagerstroemia indica L. is a well-known ornamental plant with large pyramidal racemes, long flower duration, and diverse colors and cultivars. It has been cultivated for nearly 1600 years and is essential for investigating the germplasm and assessing genetic variation to support international cultivar identification and breeding programs. In this study, 20 common Lagerstroemia indica cultivars from different varietal groups and flower morphologies, as well as multiple wild relative species, were analyzed to investigate the maternal donor of Lagerstroemia indica cultivars and to discover the genetic variation and relationships among cultivars based on plastome and nuclear ribosomal DNA (nrDNA) sequences. A total of 47 single nucleotide polymorphisms (SNPs) and 24 insertion/deletions (indels) were identified in the 20 L. indica cultivars' plastome and 25 SNPs were identified in the nrDNA. Phylogenetic analysis based on the plastome sequences showed that all the cultivars formed a clade with the species of L. indica, indicating that L. indica was the maternal donor of the cultivars. Population structure and PCA analyses supported two clades of cultivars, which exhibited significant genetic differences according to the plastome dataset. The results of the nrDNA supported that all 20 cultivars were divided into three clades and most of the cultivars had at least two genetic backgrounds and higher gene flow. Our results suggest that the plastome and nrDNA sequences can be used as molecular markers for assessing the genetic variation and relationships of L. indica cultivars.
Collapse
|
4
|
Han B, Zhang MJ, Xian Y, Xu H, Cui CC, Liu D, Wang L, Li DZ, Li WQ, Xie XM. Variations in genetic diversity in cultivated Pistacia chinensis. FRONTIERS IN PLANT SCIENCE 2022; 13:1030647. [PMID: 36438104 PMCID: PMC9691265 DOI: 10.3389/fpls.2022.1030647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 10/21/2022] [Indexed: 06/16/2023]
Abstract
Identification of the evolution history and genetic diversity of a species is important in the utilization of novel genetic variation in this species, as well as for its conservation. Pistacia chinensis is an important biodiesel tree crop in China, due to the high oil content of its fruit. The aim of this study was to uncover the genetic structure of P. chinensis and to investigate the influence of intraspecific gene flow on the process of domestication and the diversification of varieties. We investigated the genetic structure of P. chinensis, as well as evolution and introgression in the subpopulations, through analysis of the plastid and nuclear genomes of 39 P. chinensis individuals from across China. High levels of variation were detected in the P. chinensis plastome, and 460 intraspecific polymorphic sites, 104 indels and three small inversions were identified. Phylogenetic analysis and population structure using the plastome dataset supported five clades of P. chinensis. Population structure analysis based on the nuclear SNPs showed two groups, clearly clustered together, and more than a third of the total individuals were classified as hybrids. Discordance between the plastid and nuclear genomes suggested that hybridization events may have occurred between highly divergent samples in the P. chinensis subclades. Most of the species in the P. chinensis subclade diverged between the late Miocene and the mid-Pliocene. The processes of domestication and cultivation have decreased the genetic diversity of P. chinensis. The extensive variability and structuring of the P. chinensis plastid together with the nuclear genomic variation detected in this study suggests that much unexploited genetic diversity is available for improvement in this recently domesticated species.
Collapse
Affiliation(s)
- Biao Han
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji’nan, Shandong, China
| | - Ming-Jia Zhang
- College of Forestry, Shandong Agricultural University, Tai’an, Shandong, China
| | - Yang Xian
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji’nan, Shandong, China
| | - Hui Xu
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji’nan, Shandong, China
| | - Cheng-Cheng Cui
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji’nan, Shandong, China
| | - Dan Liu
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji’nan, Shandong, China
| | - Lei Wang
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji’nan, Shandong, China
| | - De-Zhu Li
- Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Wen-Qing Li
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji’nan, Shandong, China
| | - Xiao-Man Xie
- Key Laboratory of State Forestry and Grassland Administration Conservation and Utilization of Warm Temperate Zone Forest and Grass Germplasm Resources, Shandong Provincial Center of Forest and Grass Germplasm Resources, Ji’nan, Shandong, China
| |
Collapse
|
5
|
Xiao G, Zhou J, Huo Z, Wu T, Li Y, Li Y, Wang Y, Wang M. The Shift in Synonymous Codon Usage Reveals Similar Genomic Variation during Domestication of Asian and African Rice. Int J Mol Sci 2022; 23:12860. [PMID: 36361651 PMCID: PMC9656316 DOI: 10.3390/ijms232112860] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 10/20/2022] [Accepted: 10/24/2022] [Indexed: 10/29/2023] Open
Abstract
The domestication of wild rice occurred together with genomic variation, including the synonymous nucleotide substitutions that result in synonymous codon usage bias (SCUB). SCUB mirrors the evolutionary specialization of plants, but its characteristics during domestication were not yet addressed. Here, we found cytosine- and guanidine-ending (NNC and NNG) synonymous codons (SCs) were more pronounced than adenosine- and thymine-ending SCs (NNA and NNT) in both wild and cultivated species of Asian and African rice. The ratios of NNC/G to NNA/T codons gradually decreased following the rise in the number of introns, and the preference for NNA/T codons became more obvious in genes with more introns in cultivated rice when compared with those in wild rice. SCUB frequencies were heterogeneous across the exons, with a higher preference for NNA/T in internal exons than in terminal exons. The preference for NNA/T in internal but not terminal exons was more predominant in cultivated rice than in wild rice, with the difference between wild and cultivated rice becoming more remarkable with the rise in exon numbers. The difference in the ratios of codon combinations representing DNA methylation-mediated conversion from cytosine to thymine between wild and cultivated rice coincided with their difference in SCUB frequencies, suggesting that SCUB reveals the possible association between genetic and epigenetic variation during the domestication of rice. Similar patterns of SCUB shift in Asian and African rice indicate that genomic variation occurs in the same non-random manner. SCUB representing non-neutral synonymous mutations can provide insight into the mechanism of genomic variation in domestication and can be used for the genetic dissection of agricultural traits in rice and other crops.
Collapse
Affiliation(s)
- Guilian Xiao
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao 266237, China
| | - Junzhi Zhou
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao 266237, China
| | - Zhiheng Huo
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao 266237, China
| | - Tong Wu
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao 266237, China
| | - Yingchun Li
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao 266237, China
| | - Yajing Li
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao 266237, China
| | - Yanxia Wang
- Shijiazhuang Academy of Agriculture and Forestry Sciences, Shijiazhuang 050041, China
| | - Mengcheng Wang
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao 266237, China
| |
Collapse
|
6
|
Tian G, Xiao G, Wu T, Zhou J, Xu W, Wang Y, Xia G, Wang M. Alteration of synonymous codon usage bias accompanies polyploidization in wheat. Front Genet 2022; 13:979902. [PMID: 36313462 PMCID: PMC9614214 DOI: 10.3389/fgene.2022.979902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 10/03/2022] [Indexed: 11/13/2022] Open
Abstract
The diploidization of polyploid genomes is accompanied by genomic variation, including synonymous nucleotide substitutions that may lead to synonymous codon usage bias (SCUB). SCUB can mirror the evolutionary specialization of plants, but its effect on the formation of polyploidies is not well documented. We explored this issue here with hexaploid wheat and its progenitors. Synonymous codons (SCs) ending in either cytosine (NNC) or guanidine (NNG) were more frequent than those ending in either adenosine (NNA) or thymine (NNT), and the preference for NNC/G codons followed the increase in genome ploidy. The ratios between NNC/G and NNA/T codons gradually decreased in genes with more introns, and the difference in these ratios between wheat and its progenitors diminished with increasing ploidy. SCUB frequencies were heterogeneous among exons, and the bias preferred to NNA/T in more internal exons, especially for genes with more exons; while the preference did not appear to associate with ploidy. The SCUB alteration of the progenitors was different during the formation of hexaploid wheat, so that SCUB was the homogeneous among A, B and D subgenomes. DNA methylation-mediated conversion from cytosine to thymine weakened following the increase of genome ploidy, coinciding with the stronger bias for NNC/G SCs in the genome as a function of ploidy, suggesting that SCUB contribute to the epigenetic variation in hexaploid wheat. The patterns in SCUB mirrored the formation of hexaploid wheat, which provides new insight into genome shock-induced genetic variation during polyploidization. SCs representing non-neutral synonymous mutations can be used for genetic dissection and improvement of agricultural traits of wheat and other polyploidies.
Collapse
Affiliation(s)
- Geng Tian
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, China
| | - Guilian Xiao
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, China
| | - Tong Wu
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, China
| | - Junzhi Zhou
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, China
| | - Wenjing Xu
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, China
| | - Yanxia Wang
- Shijiazhuang Academy of Agriculture and Forestry Sciences, Shijiazhuang, China
| | - Guangmin Xia
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, China
| | - Mengcheng Wang
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, China
- *Correspondence: Mengcheng Wang,
| |
Collapse
|
7
|
Sun J, Wang S, Wang Y, Wang R, Liu K, Li E, Qiao P, Shi L, Dong W, Huang L, Guo L. Phylogenomics and Genetic Diversity of Arnebiae Radix and Its Allies ( Arnebia, Boraginaceae) in China. FRONTIERS IN PLANT SCIENCE 2022; 13:920826. [PMID: 35755641 PMCID: PMC9218939 DOI: 10.3389/fpls.2022.920826] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 05/11/2022] [Indexed: 05/03/2023]
Abstract
Arnebiae Radix is a traditional medicine with pleiotropic properties that has been used for several 100 years. There are five species of Arnebia in China, and the two species Arnebia euchroma and Arnebia guttata are the source plants of Arnebiae Radix according to the Chinese Pharmacopoeia. Molecular markers that permit species identification and facilitate studies of the genetic diversity and divergence of the wild populations of these two source plants have not yet been developed. Here, we sequenced the chloroplast genomes of 56 samples of five Arnebia species using genome skimming methods. The Arnebia chloroplast genomes exhibited quadripartite structures with lengths from 149,539 and 152,040 bp. Three variable markers (rps16-trnQ, ndhF-rpl32, and ycf1b) were identified, and these markers exhibited more variable sites than universal chloroplast markers. The phylogenetic relationships among the five Arnebia species were completely resolved using the whole chloroplast genome sequences. Arnebia arose during the Oligocene and diversified in the middle Miocene; this coincided with two geological events during the late Oligocene and early Miocene: warming and the progressive uplift of Tianshan and the Himalayas. Our analyses revealed that A. euchroma and A. guttata have high levels of genetic diversity and comprise two and three subclades, respectively. The two clades of A. euchroma exhibited significant genetic differences and diverged at 10.18 Ma in the middle Miocene. Three clades of A. guttata diverged in the Pleistocene. The results provided new insight into evolutionary history of Arnebia species and promoted the conservation and exploitation of A. euchroma and A. guttata.
Collapse
Affiliation(s)
- Jiahui Sun
- State Key Laboratory Breeding Base of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China
| | - Sheng Wang
- State Key Laboratory Breeding Base of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yiheng Wang
- State Key Laboratory Breeding Base of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China
| | - Ruishan Wang
- State Key Laboratory Breeding Base of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China
| | - Kangjia Liu
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China
| | - Enze Li
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China
| | - Ping Qiao
- State Key Laboratory Breeding Base of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China
| | - Linyuan Shi
- State Key Laboratory Breeding Base of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China
| | - Wenpan Dong
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China
| | - Luqi Huang
- State Key Laboratory Breeding Base of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China
| | - Lanping Guo
- State Key Laboratory Breeding Base of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China
| |
Collapse
|
8
|
The Roles of Mutation and Selection Acting on Mitochondrial Genomes Inferred from Intraspecific Variation in Seed Plants. Genes (Basel) 2022; 13:genes13061036. [PMID: 35741799 PMCID: PMC9222611 DOI: 10.3390/genes13061036] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 05/20/2022] [Accepted: 06/07/2022] [Indexed: 12/03/2022] Open
Abstract
There is a paradox in the plant mitochondrial genome, that is, the genic region evolves slowly while the intergenic region evolves rapidly. Thus, the intergenic regions of the plant mitochondrial genome are difficult to align across different species, even in closely related species. Here, to character the mechanism of this paradox, we identified interspecific variations in the Ginkgo biloba, Oryza sativa, and Arabidopsis thaliana mitochondrial and plastid genome at a genome-wide level. The substitution rate of synonymous sites in genic regions was similar to the substitution rate of intergenic regions, while the substitution rate of nonsynonymous sites in genic regions was lower than that in intergenic regions, suggesting the mutation inputs were the same among different categories within the organelle genome, but the selection pressure varied. The substitution rate of single-copy regions was higher than that of IR (inverted repeats) in the plastid genome at an intraspecific level. The substitution rate of single-copy regions was higher than that of repeats in the G. biloba and A. thaliana mitochondrial genomes, but lower in that of O. sativa. This difference may be related to the length and distribution of repeats. Copy number variations that existed in the G. biloba and O. sativa mitochondrial genomes were confirmed. This study reveals the intraspecific variation pattern of organelle genomes at a genome-wide level, and that copy number variations were common in plant mitochondrial genomes.
Collapse
|
9
|
David P, Degletagne C, Saclier N, Jennan A, Jarne P, Plénet S, Konecny L, François C, Guéguen L, Garcia N, Lefébure T, Luquet E. Extreme mitochondrial DNA divergence underlies genetic conflict over sex determination. Curr Biol 2022; 32:2325-2333.e6. [PMID: 35483362 DOI: 10.1016/j.cub.2022.04.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 03/28/2022] [Accepted: 04/06/2022] [Indexed: 01/06/2023]
Abstract
Cytoplasmic male sterility (CMS) is a form of genetic conflict over sex determination that results from differences in modes of inheritance between genomic compartments.1-3 Indeed, maternally transmitted (usually mitochondrial) genes sometimes enhance their transmission by suppressing the male function in a hermaphroditic organism to the detriment of biparentally inherited nuclear genes. Therefore, these hermaphrodites become functionally female and may coexist with regular hermaphrodites in so-called gynodioecious populations.3 CMS has been known in plants since Darwin's times4 but is previously unknown in the animal kingdom.5-8 We relate the first observation of CMS in animals. It occurs in a freshwater snail population, where some individuals appear unable to sire offspring in controlled crosses and show anatomical, physiological, and behavioral characters consistent with a suppression of the male function. Male sterility is associated with a mitochondrial lineage that underwent a spectacular acceleration of DNA substitution rates, affecting the entire mitochondrial genome-this acceleration concerns both synonymous and non-synonymous substitutions and therefore results from increased mitogenome mutation rates. Consequently, mitochondrial haplotype divergence within the population is exceptionally high, matching that observed between snail taxa that diverged 475 million years ago. This result is reminiscent of similar accelerations in mitogenome evolution observed in plant clades where gynodioecy is frequent,9,10 both being consistent with arms-race evolution of genome regions implicated in CMS.11,12 Our study shows that genomic conflicts can trigger independent evolution of similar sex-determination systems in plants and animals and dramatically accelerate molecular evolution.
Collapse
Affiliation(s)
- Patrice David
- CEFE, CNRS, University of Montpellier, IRD, EPHE, Montpellier, France.
| | - Cyril Degletagne
- University of Lyon, CNRS, ENTPE, UMR5023 LEHNA, 69622 Villeurbanne, France
| | | | - Aurel Jennan
- University of Lyon, CNRS, ENTPE, UMR5023 LEHNA, 69622 Villeurbanne, France
| | - Philippe Jarne
- CEFE, CNRS, University of Montpellier, IRD, EPHE, Montpellier, France
| | - Sandrine Plénet
- University of Lyon, CNRS, ENTPE, UMR5023 LEHNA, 69622 Villeurbanne, France
| | - Lara Konecny
- University of Lyon, CNRS, ENTPE, UMR5023 LEHNA, 69622 Villeurbanne, France
| | | | - Laurent Guéguen
- University of Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5558, Laboratoire de Biométrie et Biologie Evolutive, Villeurbanne, France
| | - Noéline Garcia
- University of Lyon, CNRS, ENTPE, UMR5023 LEHNA, 69622 Villeurbanne, France
| | - Tristan Lefébure
- University of Lyon, CNRS, ENTPE, UMR5023 LEHNA, 69622 Villeurbanne, France
| | - Emilien Luquet
- University of Lyon, CNRS, ENTPE, UMR5023 LEHNA, 69622 Villeurbanne, France
| |
Collapse
|
10
|
Plaschil S, Abel S, Klocke E. The variability of nuclear DNA content of different Pelargonium species estimated by flow cytometry. PLoS One 2022; 17:e0267496. [PMID: 35482804 PMCID: PMC9049363 DOI: 10.1371/journal.pone.0267496] [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: 01/13/2022] [Accepted: 04/08/2022] [Indexed: 11/24/2022] Open
Abstract
Pelargonium is a versatile genus mainly from the Cape Region, South Africa. The genus is divided into four subgenera and 16 sections characterized by several groups of chromosomes sizes and numbers. The DNA content of species from all subgenera and sections of Pelargonium, except for the sections Subsucculentia and Campylia was estimated using flow cytometry. Nuclei of Pelargonium samples (leaf or petal tissue) and an internal plant standard (leaf tissue) were isolated together and stained with propidium iodide. The DNA content was estimated providing that the 2C peaks of sample and standard be in linearity in the flow cytometer histograms. In total, 96 Pelargonium accessions of 60 species (22 Pelargonium species for the first time) were analyzed. The 2C DNA content ranged from 0.84 pg (P. longifolium, section Hoarea) to 6.69 pg (P. schizopetalum, section Magnistipulacea) and the corresponding 1Cx DNA content from 0.42 pg (P. longifolium) to 1.72 pg (P. transvaalense. This demonstrates the high plasticity within the genus Pelargonium. Some species, such as P. peltatum accessions revealed a pronounced endopolyploidization in leaves but not in petals underlining the importance to choose the right tissue as sample for the flow cytometry analysis. The reported genome sizes are a step forward towards the characterization of the Pelargonium collection within the German Gene Bank for Ornamental Plants and a valuable base for future sequencing programs of the Pelargonium genomes.
Collapse
Affiliation(s)
- Sylvia Plaschil
- Julius Kühn Institute (JKI)—Federal Research Centre of Cultivated Plants, Institute for Breeding Research on Horticultural Crops, Quedlinburg, Germany
- * E-mail:
| | - Simone Abel
- Julius Kühn Institute (JKI)—Federal Research Centre of Cultivated Plants, Institute for Breeding Research on Horticultural Crops, Quedlinburg, Germany
| | - Evelyn Klocke
- Julius Kühn Institute (JKI)—Federal Research Centre of Cultivated Plants, Institute for Breeding Research on Horticultural Crops, Quedlinburg, Germany
| |
Collapse
|
11
|
Dong W, Li E, Liu Y, Xu C, Wang Y, Liu K, Cui X, Sun J, Suo Z, Zhang Z, Wen J, Zhou S. Phylogenomic approaches untangle early divergences and complex diversifications of the olive plant family. BMC Biol 2022; 20:92. [PMID: 35468824 PMCID: PMC9040247 DOI: 10.1186/s12915-022-01297-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 04/13/2022] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Deep-branching phylogenetic relationships are often difficult to resolve because phylogenetic signals are obscured by the long history and complexity of evolutionary processes, such as ancient introgression/hybridization, polyploidization, and incomplete lineage sorting (ILS). Phylogenomics has been effective in providing information for resolving both deep- and shallow-scale relationships across all branches of the tree of life. The olive family (Oleaceae) is composed of 25 genera classified into five tribes with tribe Oleeae consisting of four subtribes. Previous phylogenetic analyses showed that ILS and/or hybridization led to phylogenetic incongruence in the family. It was essential to distinguish phylogenetic signal conflicts, and explore mechanisms for the uncertainties concerning relationships of the olive family, especially at the deep-branching nodes. RESULTS We used the whole plastid genome and nuclear single nucleotide polymorphism (SNP) data to infer the phylogenetic relationships and to assess the variation and rates among the main clades of the olive family. We also used 2608 and 1865 orthologous nuclear genes to infer the deep-branching relationships among tribes of Oleaceae and subtribes of tribe Oleeae, respectively. Concatenated and coalescence trees based on the plastid genome, nuclear SNPs and multiple nuclear genes suggest events of ILS and/or ancient introgression during the diversification of Oleaceae. Additionally, there was extreme heterogeneity in the substitution rates across the tribes. Furthermore, our results supported that introgression/hybridization, rather than ILS, is the main factor for phylogenetic discordance among the five tribes of Oleaceae. The tribe Oleeae is supported to have originated via ancient hybridization and polyploidy, and its most likely parentages are the ancestral lineage of Jasmineae or its sister group, which is a "ghost lineage," and Forsythieae. However, ILS and ancient introgression are mainly responsible for the phylogenetic discordance among the four subtribes of tribe Oleeae. CONCLUSIONS This study showcases that using multiple sequence datasets (plastid genomes, nuclear SNPs and thousands of nuclear genes) and diverse phylogenomic methods such as data partition, heterogeneous models, quantifying introgression via branch lengths (QuIBL) analysis, and species network analysis can facilitate untangling long and complex evolutionary processes of ancient introgression, paleopolyploidization, and ILS.
Collapse
Affiliation(s)
- Wenpan Dong
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China.
| | - Enze Li
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China
| | - Yanlei Liu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Chao Xu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Yushuang Wang
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China
| | - Kangjia Liu
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China
| | - Xingyong Cui
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China
| | - Jiahui Sun
- State Key Laboratory Breeding Base of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, 100700, China.
| | - Zhili Suo
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Zhixiang Zhang
- Laboratory of Systematic Evolution and Biogeography of Woody Plants, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, 100083, China
| | - Jun Wen
- Department of Botany, National Museum of Natural History, Smithsonian Institution, Washington, DC, 20013-7012, USA.
| | - Shiliang Zhou
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| |
Collapse
|
12
|
Mower JP, Guo W, Partha R, Fan W, Levsen N, Wolff K, Nugent JM, Pabón-Mora N, González F. Plastomes from tribe Plantagineae (Plantaginaceae) reveal infrageneric structural synapormorphies and localized hypermutation for Plantago and functional loss of ndh genes from Littorella. Mol Phylogenet Evol 2021; 162:107217. [PMID: 34082129 DOI: 10.1016/j.ympev.2021.107217] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 05/14/2021] [Accepted: 05/27/2021] [Indexed: 10/21/2022]
Abstract
Tribe Plantagineae (Plantaginaceae) comprises ~ 270 species in three currently recognized genera (Aragoa, Littorella, Plantago), of which Plantago is most speciose. Plantago plastomes exhibit several atypical features including large inversions, expansions of the inverted repeat, increased repetitiveness, intron losses, and gene-specific increases in substitution rate, but the prevalence of these plastid features among species and subgenera is unknown. To assess phylogenetic relationships and plastomic evolutionary dynamics among Plantagineae genera and Plantago subgenera, we generated 25 complete plastome sequences and compared them with existing plastome sequences from Plantaginaceae. Using whole plastome and partitioned alignments, our phylogenomic analyses provided strong support for relationships among major Plantagineae lineages. General plastid features-including size, GC content, intron content, and indels-provided additional support that reinforced major Plantagineae subdivisions. Plastomes from Plantago subgenera Plantago and Coronopus have synapomorphic expansions and inversions affecting the size and gene order of the inverted repeats, and particular genes near the inversion breakpoints exhibit accelerated nucleotide substitution rates, suggesting localized hypermutation associated with rearrangements. The Littorella plastome lacks functional copies of ndh genes, which may be related to an amphibious lifestyle and partial reliance on CAM photosynthesis.
Collapse
Affiliation(s)
- Jeffrey P Mower
- Center for Plant Science Innovation, University of Nebraska, Lincoln, NE 68588, USA; Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE 68583, USA.
| | - Wenhu Guo
- Center for Plant Science Innovation, University of Nebraska, Lincoln, NE 68588, USA; School of Biological Sciences, University of Nebraska, Lincoln, NE 68588, USA
| | - Raghavendran Partha
- Center for Plant Science Innovation, University of Nebraska, Lincoln, NE 68588, USA
| | - Weishu Fan
- Center for Plant Science Innovation, University of Nebraska, Lincoln, NE 68588, USA; Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE 68583, USA
| | - Nick Levsen
- School of Natural and Environmental Sciences, Newcastle University, Newcastle Upon Tyne NE1 7RU, UK
| | - Kirsten Wolff
- School of Natural and Environmental Sciences, Newcastle University, Newcastle Upon Tyne NE1 7RU, UK
| | - Jacqueline M Nugent
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Natalia Pabón-Mora
- Instituto de Biología, Universidad de Antioquia, Apartado 1226, Medellín, Colombia
| | - Favio González
- Universidad Nacional de Colombia, Sede Bogotá, Facultad de Ciencias, Instituto de Ciencias Naturales, Apartado 7495, Colombia
| |
Collapse
|