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Fields PD, Weber MM, Waneka G, Broz AK, Sloan DB. Chromosome-Level Genome Assembly for the Angiosperm Silene conica. Genome Biol Evol 2023; 15:evad192. [PMID: 37862134 PMCID: PMC10630074 DOI: 10.1093/gbe/evad192] [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: 09/05/2023] [Revised: 09/28/2023] [Accepted: 10/16/2023] [Indexed: 10/22/2023] Open
Abstract
The angiosperm genus Silene has been the subject of extensive study in the field of ecology and evolution, but the availability of high-quality reference genome sequences has been limited for this group. Here, we report a chromosome-level assembly for the genome of Silene conica based on Pacific Bioscience HiFi, Hi-C, and Bionano technologies. The assembly produced 10 scaffolds (1 per chromosome) with a total length of 862 Mb and only ∼1% gap content. These results confirm previous observations that S. conica and its relatives have a reduced base chromosome number relative to the genus's ancestral state of 12. Silene conica has an exceptionally large mitochondrial genome (>11 Mb), predominantly consisting of sequence of unknown origins. Analysis of shared sequence content suggests that it is unlikely that transfer of nuclear DNA is the primary driver of this mitochondrial genome expansion. More generally, this assembly should provide a valuable resource for future genomic studies in Silene, including comparative analyses with related species that recently evolved sex chromosomes.
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Affiliation(s)
- Peter D Fields
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
- Mammalian Genetics, The Jackson Laboratory, Bar Harbor, Maine, USA
| | - Melody M Weber
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Gus Waneka
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Amanda K Broz
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
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2
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Fields PD, Weber MM, Waneka G, Broz AK, Sloan DB. Chromosome-level genome assembly for the angiosperm Silene conica. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.05.556365. [PMID: 37732249 PMCID: PMC10508779 DOI: 10.1101/2023.09.05.556365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
The angiosperm genus Silene has been the subject of extensive study in the field of ecology and evolution, but the availability of high-quality reference genome sequences has been limited for this group. Here, we report a chromosome-level assembly for the genome of Silene conica based on PacBio HiFi, Hi-C and Bionano technologies. The assembly produced 10 scaffolds (one per chromosome) with a total length of 862 Mb and only ~1% gap content. These results confirm previous observations that S. conica and its relatives have a reduced base chromosome number relative to the genus's ancestral state of 12. Silene conica has an exceptionally large mitochondrial genome (>11 Mb), predominantly consisting of sequence of unknown origins. Analysis of shared sequence content suggests that it is unlikely that transfer of nuclear DNA is the primary driver of this mitochondrial genome expansion. More generally, this assembly should provide a valuable resource for future genomic studies in Silene, including comparative analyses with related species that recently evolved sex chromosomes. Significance Whole-genome sequences have been largely lacking for species in the genus Silene even though these flowering plants have been used for studying ecology, evolution, and genetics for over a century. Here, we address this gap by providing a high-quality nuclear genome assembly for S. conica, a species known to have greatly accelerated rates of sequence and structural divergence in its mitochondrial and plastid genomes. This resource will be valuable in understanding the coevolutionary interactions between nuclear and cytoplasmic genomes and in comparative analyses across this highly diverse genus.
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Affiliation(s)
- Peter D. Fields
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
- Mammalian Genetics, The Jackson Laboratory, Bar Harbor, Maine, USA
| | - Melody M. Weber
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Gus Waneka
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Amanda K. Broz
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Daniel B. Sloan
- Department of Biology, Colorado State University, Fort Collins, Colorado, USA
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Liu Q, Zang EH, Wang CC, Liu YC, Niu H, Gao Y, Li MH. Dianthi herba: a comprehensive review of its botany, traditional use, phytochemistry, and pharmacology. Chin Med 2022; 17:15. [PMID: 35062995 PMCID: PMC8780776 DOI: 10.1186/s13020-022-00570-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 01/07/2022] [Indexed: 11/24/2022] Open
Abstract
Dianthi herba (called “Qumai” in Chinese) is the dried aerial part of Dianthus superbus L. and Dianthus chinensis L. The species are mainly distributed in the temperate and warm temperate regions in the northern hemisphere, and some regions in Africa and Oceania, as well as South America. However, the distribution pattern of Dianthi herba has not been reviewed. In this review, we summarize the research progress on the botany, traditional use, phytochemistry, pharmacology, toxicology, and clinical applications of Dianthi herba. Approximately 194 chemical compounds have been identified and isolated from Dianthi herba, the most important being triterpenoid saponins, flavonoids, and volatile oil compounds. These compounds possess antiviral, anticancer, antioxidant, and antimicrobial properties, inter alia. Further studies should be carried out on Dianthi herba to elucidate more of its active principles and their mechanisms of action.
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Williams AM, Itgen MW, Broz AK, Carter OG, Sloan DB. Long-read transcriptome and other genomic resources for the angiosperm Silene noctiflora. G3 (BETHESDA, MD.) 2021; 11:jkab189. [PMID: 34849814 PMCID: PMC8496259 DOI: 10.1093/g3journal/jkab189] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 05/20/2021] [Indexed: 01/04/2023]
Abstract
The angiosperm genus Silene is a model system for several traits of ecological and evolutionary significance in plants, including breeding system and sex chromosome evolution, host-pathogen interactions, invasive species biology, heavy metal tolerance, and cytonuclear interactions. Despite its importance, genomic resources for this large genus of approximately 850 species are scarce, with only one published whole-genome sequence (from the dioecious species Silene latifolia). Here, we provide genomic and transcriptomic resources for a hermaphroditic representative of this genus (S. noctiflora), including a PacBio Iso-Seq transcriptome, which uses long-read, single-molecule sequencing technology to analyze full-length mRNA transcripts. Using these data, we have assembled and annotated high-quality full-length cDNA sequences for approximately 14,126 S. noctiflora genes and 25,317 isoforms. We demonstrated the utility of these data to distinguish between recent and highly similar gene duplicates by identifying novel paralogous genes in an essential protease complex. Furthermore, we provide a draft assembly for the approximately 2.7-Gb genome of this species, which is near the upper range of genome-size values reported for diploids in this genus and threefold larger than the 0.9-Gb genome of Silene conica, another species in the same subgenus. Karyotyping confirmed that S. noctiflora is a diploid, indicating that its large genome size is not due to polyploidization. These resources should facilitate further study and development of this genus as a model in plant ecology and evolution.
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Affiliation(s)
- Alissa M Williams
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
- Cell and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO 80523, USA
| | - Michael W Itgen
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Amanda K Broz
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Olivia G Carter
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
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Chen J, Li R, Xia Y, Bai G, Guo P, Wang Z, Zhang H, Siddique KHM. Development of EST-SSR markers in flowering Chinese cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee) based on de novo transcriptomic assemblies. PLoS One 2017; 12:e0184736. [PMID: 28902884 PMCID: PMC5597223 DOI: 10.1371/journal.pone.0184736] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Accepted: 08/30/2017] [Indexed: 11/18/2022] Open
Abstract
Flowering Chinese cabbage is one of the most important vegetable crops in southern China. Genetic improvement of various agronomic traits in this crop is underway to meet high market demand in the region, but the progress is hampered by limited number of molecular markers available in this crop. This study aimed to develop EST-SSR markers from transcriptome sequences generated by next-generation sequencing. RNA-seq of eight cabbage samples identified 48,975 unigenes. Of these unigenes, 23,267 were annotated in 56 gene ontology (GO) categories, 6,033 were mapped to 131 KEGG pathways, and 7,825 were assigned to clusters of orthologous groups (COGs). From the unigenes, 8,165 EST-SSR loci were identified and 98.57% of them were 1-3 nucleotide repeats with 14.32%, 41.08% and 43.17% of mono-, di- and tri-nucleotide repeats, respectively. Fifty-eight types of motifs were identified with A/T, AG/CT, AT/AT, AC/GT, AAG/CTT and AGG/CCT the most abundant. The lengths of repeated nucleotide sequences in all SSR loci ranged from 12 to 60 bp, with most (88.51%) under 20 bp. Among 170 primer pairs were randomly selected from a total of 4,912 SSR primers we designed, 48 yielded unambiguously polymorphic bands with high reproducibility. Cluster analysis using 48 SSRs classified 34 flowering Chinese cabbage cultivars into three groups. A large number of EST-SSR markers identified in this study will facilitate marker-assisted selection in the breeding programs of flowering Chinese cabbage.
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Affiliation(s)
- Jingfang Chen
- International Crop Research Center for Stress Resistance, College of Life Sciences, Guangzhou University, Guangzhou, China
| | - Ronghua Li
- International Crop Research Center for Stress Resistance, College of Life Sciences, Guangzhou University, Guangzhou, China
| | - Yanshi Xia
- International Crop Research Center for Stress Resistance, College of Life Sciences, Guangzhou University, Guangzhou, China
| | - Guihua Bai
- Hard Winter Wheat Genetics Research Unit, United States Department of Agriculture–Agricultural Research Service, Manhattan, Kansas, United States of America
| | - Peiguo Guo
- International Crop Research Center for Stress Resistance, College of Life Sciences, Guangzhou University, Guangzhou, China
- * E-mail:
| | - Zhiliang Wang
- International Crop Research Center for Stress Resistance, College of Life Sciences, Guangzhou University, Guangzhou, China
| | - Hua Zhang
- Guangzhou Academy of Agricultural Sciences, Guangzhou, China
| | - Kadambot H. M. Siddique
- The UWA Institute of Agriculture and School of Agriculture & Environment, The University of Western Australia, Perth WA, Australia
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Evaluation of reference genes for reverse transcription quantitative real-time PCR (RT-qPCR) studies in Silene vulgaris considering the method of cDNA preparation. PLoS One 2017; 12:e0183470. [PMID: 28817728 PMCID: PMC5560574 DOI: 10.1371/journal.pone.0183470] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 08/04/2017] [Indexed: 01/05/2023] Open
Abstract
Accurate gene expression measurements are essential in studies of both crop and wild plants. Reverse transcription quantitative real-time PCR (RT-qPCR) has become a preferred tool for gene expression estimation. A selection of suitable reference genes for the normalization of transcript levels is an essential prerequisite of accurate RT-qPCR results. We evaluated the expression stability of eight candidate reference genes across roots, leaves, flower buds and pollen of Silene vulgaris (bladder campion), a model plant for the study of gynodioecy. As random priming of cDNA is recommended for the study of organellar transcripts and poly(A) selection is indicated for nuclear transcripts, we estimated gene expression with both random-primed and oligo(dT)-primed cDNA. Accordingly, we determined reference genes that perform well with oligo(dT)- and random-primed cDNA, making it possible to estimate levels of nucleus-derived transcripts in the same cDNA samples as used for organellar transcripts, a key benefit in studies of cyto-nuclear interactions. Gene expression variance was estimated by RefFinder, which integrates four different analytical tools. The SvACT and SvGAPDH genes were the most stable candidates across various organs of S. vulgaris, regardless of whether pollen was included or not.
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Feurtey A, Gladieux P, Hood ME, Snirc A, Cornille A, Rosenthal L, Giraud T. Strong phylogeographic co-structure between the anther-smut fungus and its white campion host. THE NEW PHYTOLOGIST 2016; 212:668-679. [PMID: 27500396 DOI: 10.1111/nph.14125] [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: 05/20/2016] [Accepted: 06/18/2016] [Indexed: 06/06/2023]
Abstract
Although congruence between host and pathogen phylogenies has been extensively investigated, the congruence between host and pathogen genetic structures at the within-species level has received little attention. Using an unprecedented and comprehensive collection of associated plant-pathogen samples, we investigated the degree of congruence between the genetic structures across Europe of two evolutionary and ecological model organisms, the anther-smut pathogen Microbotryum lychnidis-dioicae and its host plant Silene latifolia. We demonstrated a significant and particularly strong level of host-pathogen co-structure, with three main genetic clusters displaying highly similar spatial ranges in Western Europe, Eastern Europe and Italy, respectively. Correcting for the geographical component of genetic variation, significant correlations were still found between the genetic distances of anther-smut and host populations. Inoculation experiments suggested plant local adaptation, at the cluster level, for resistance to pathogens. These findings indicate that the pathogen remained isolated in the same fragmented southern refugia as its host plant during the last glaciation, and that little long-distance dispersal has occurred since the recolonization of Europe for either the plant or the pathogen, despite their known ability to travel across continents. This, together with the inoculation results, suggests that coevolutionary and competitive processes may be drivers of host-pathogen co-structure.
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Affiliation(s)
- Alice Feurtey
- Ecologie Systématique Evolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Orsay, 91400, France
| | - Pierre Gladieux
- Ecologie Systématique Evolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Orsay, 91400, France
- UMR BGPI, INRA, Montpellier, 34398, France
| | - Michael E Hood
- Department of Biology, Amherst College, Amherst, MA, 01002, USA
| | - Alodie Snirc
- Ecologie Systématique Evolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Orsay, 91400, France
| | - Amandine Cornille
- Ecologie Systématique Evolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Orsay, 91400, France
| | - Lisa Rosenthal
- Department of Biology, Amherst College, Amherst, MA, 01002, USA
| | - Tatiana Giraud
- Ecologie Systématique Evolution, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, Orsay, 91400, France.
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Casimiro-Soriguer I, Narbona E, Buide ML, del Valle JC, Whittall JB. Transcriptome and Biochemical Analysis of a Flower Color Polymorphism in Silene littorea (Caryophyllaceae). FRONTIERS IN PLANT SCIENCE 2016; 7:204. [PMID: 26973662 PMCID: PMC4770042 DOI: 10.3389/fpls.2016.00204] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 02/06/2016] [Indexed: 05/23/2023]
Abstract
Flower color polymorphisms are widely used as model traits from genetics to ecology, yet determining the biochemical and molecular basis can be challenging. Anthocyanin-based flower color variations can be caused by at least 12 structural and three regulatory genes in the anthocyanin biosynthetic pathway (ABP). We use mRNA-Seq to simultaneously sequence and estimate expression of these candidate genes in nine samples of Silene littorea representing three color morphs (dark pink, light pink and white) across three developmental stages in hopes of identifying the cause of flower color variation. We identified 29 putative paralogs for the 15 candidate genes in the ABP. We assembled complete coding sequences for 16 structural loci and nine of ten regulatory loci. Among these 29 putative paralogs, we identified 622 SNPs, yet only nine synonymous SNPs in Ans had allele frequencies that differentiated pigmented petals (dark pink and light pink) from white petals. These Ans allele frequency differences were further investigated with an expanded sequencing survey of 38 individuals, yet no SNPs consistently differentiated the color morphs. We also found one locus, F3h1, with strong differential expression between pigmented and white samples (>42x). This may be caused by decreased expression of Myb1a in white petal buds. Myb1a in S. littorea is a regulatory locus closely related to Subgroup 7 Mybs known to regulate F3h and other loci in the first half of the ABP in model species. We then compare the mRNA-Seq results with petal biochemistry which revealed cyanidin as the primary anthocyanin and five flavonoid intermediates. Concentrations of three of the flavonoid intermediates were significantly lower in white petals than in pigmented petals (rutin, quercetin and isovitexin). The biochemistry results for rutin, quercetin, luteolin and apigenin are consistent with the transcriptome results suggesting a blockage at F3h, possibly caused by downregulation of Myb1a.
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Affiliation(s)
- Inés Casimiro-Soriguer
- Department of Molecular Biology and Biochemical Engineering, Pablo de Olavide UniversitySeville, Spain
- Department of Plant Biology and Ecology, University of SevilleSeville, Spain
| | - Eduardo Narbona
- Department of Molecular Biology and Biochemical Engineering, Pablo de Olavide UniversitySeville, Spain
| | - M. L. Buide
- Department of Molecular Biology and Biochemical Engineering, Pablo de Olavide UniversitySeville, Spain
| | - José C. del Valle
- Department of Molecular Biology and Biochemical Engineering, Pablo de Olavide UniversitySeville, Spain
| | - Justen B. Whittall
- Department of Biology, Santa Clara University, College of Arts and SciencesSanta Clara, CA, USA
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Ingle EKS, Gilmartin PM. Molecular characterisation of four double-flowered mutants of Silene dioica representing four centuries of variation. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:3297-3307. [PMID: 25878355 PMCID: PMC4449544 DOI: 10.1093/jxb/erv139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Records of double-flowered Silene dioica date from the late sixteenth century and four named varieties are grown today, as previously, for their horticultural interest. Although double-flowered mutants have been characterized in several plants, their study in dioecious species is of particular interest due to influences of the homeotic mutation on the different floral whorl configurations in males and females. We have analysed four double-flowered varieties of Silene dioica: Flore Pleno and Rosea Plena date back to the seventeenth and nineteenth centuries, Thelma Kay and Firefly were recognized in the latter part of the twentieth and early twenty-first centuries. We have analysed the floral structure of the four varieties, which have distinct floral architectures. Based on Y chromosome-specific PCR analysis we show that Firefly is male and that the other three varieties are female: Random Amplification of Polymorphic DNA (RAPD) analyses suggested a common origin for the three female varieties. The double-flowered phenotype in all four varieties is caused by mutation of the C-function MADS-box transcription factor gene SDM1. We show that Firefly carries a unique 44bp insertion into SDM1, revealing an independent origin for this variety. Comparative analysis of SDM1 cDNA and genomic sequences in Flore Pleno, Rosea Plena and Thelma Kay shows that all three are caused by the same 7bp insertion within SDM1 and therefore share a common origin. The three alleles also differ by several single nucleotide polymorphisms, which represent somatic mutations accumulated over four centuries of asexual propagation.
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Affiliation(s)
- Elizabeth K S Ingle
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK John Innes Centre, Norwich Research Park, Colney Lane, Norwich NR4 7UH, UK
| | - Philip M Gilmartin
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK John Innes Centre, Norwich Research Park, Colney Lane, Norwich NR4 7UH, UK
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Nevrtalova E, Baloun J, Hudzieczek V, Cegan R, Vyskot B, Dolezel J, Safar J, Milde D, Hobza R. Expression response of duplicated metallothionein 3 gene to copper stress in Silene vulgaris ecotypes. PROTOPLASMA 2014; 251:1427-1439. [PMID: 24748066 DOI: 10.1007/s00709-014-0644-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 04/02/2014] [Indexed: 06/03/2023]
Abstract
Metallothioneins (MTs) were identified as important players in metal metabolism. MT3 gene presents a key metallothionein controlling copper homeostasis in plants. We have selected one cupricolous and one non-cupricolous ecotype to isolate and analyse the MT3 gene in Silene vulgaris. For expression data comparison, we have also included other metal-tolerant ecotypes. Based on a S. vulgaris BAC library screening, we have identified and sequenced a genomic clone containing MT3 gene (SvMT3). We found that SvMT3 gene has been locally duplicated in a tandem arrangement. Expression analysis and complementation studies using yeast mutants showed that both copies of the SvMT3 gene were functional. Moreover, we examined the expression of MT3 gene(s) in selected ecotypes under different copper treatments to show the tissue-specific expression response to copper stress. We demonstrated that higher copper concentrations specifically affected MT3 expression among ecotypes. Our analysis shows that MT3a has similar expression pattern in cupricolous ecotypes while MT3b has common expression features shared by all metallophyte S. vulgaris ecotypes. Our data indicate that down-regulation of MT3b root expression in higher copper concentrations is associated with copper stress. We propose that there might be a specific regulation of SvMT3s transcription depending on the type of heavy metal tolerance.
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Affiliation(s)
- Eva Nevrtalova
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, 612 65, Brno, Czech Republic,
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Baloun J, Nevrtalova E, Kovacova V, Hudzieczek V, Cegan R, Vyskot B, Hobza R. Characterization of the HMA7 gene and transcriptomic analysis of candidate genes for copper tolerance in two Silene vulgaris ecotypes. JOURNAL OF PLANT PHYSIOLOGY 2014; 171:1188-96. [PMID: 24973591 DOI: 10.1016/j.jplph.2014.04.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 04/07/2014] [Accepted: 04/07/2014] [Indexed: 05/25/2023]
Abstract
Silene vulgaris possesses ecotype-specific tolerance to high levels of copper in the soil. Although this was reported a few decades ago, little is known about this trait on a molecular level. The aim of this study was to analyze the transcription response to elevated copper concentrations in two S. vulgaris ecotypes originating from copper-contrasting soil types - copper-tolerant Lubietova and copper-sensitive Stranska skala. To reveal if plants are transcriptionally affected, we first analyzed the HMA7 gene, a known key player in copper metabolism. Based on BAC library screening, we identified a BAC clone containing a SvHMA7 sequence with all the structural properties specific for plant copper-transporting ATPases. The functionality of the gene was tested using heterologous complementation in yeast mutants. Analyses of SvHMA7 transcription patterns showed that both ecotypes studied up-regulated SvHMA7 transcription after the copper treatment. Our data are supported by analysis of appropriate reference genes based on RNA-Seq databases. To identify genes specifically involved in copper response in the studied ecotypes, we analyzed transcription profiles of genes coding Cu-transporting proteins and genes involved in the prevention of copper-induced oxidative stress in both ecotypes. Our data show that three genes (APx, POD and COPT5) differ in their transcription pattern between the ecotypes with constitutively increased transcription in Lubietova. Taken together, we have identified transcription differences between metallifferous and non-metalliferous ecotypes of S. vulgaris, and we have suggested candidate genes participating in metal tolerance in this species.
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Affiliation(s)
- Jiri Baloun
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, CZ-612 00 Brno, Czech Republic.
| | - Eva Nevrtalova
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, CZ-612 00 Brno, Czech Republic; Department of Plant Biology, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, CZ-613 00 Brno, Czech Republic
| | - Viera Kovacova
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, CZ-612 00 Brno, Czech Republic
| | - Vojtech Hudzieczek
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, CZ-612 00 Brno, Czech Republic
| | - Radim Cegan
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, CZ-612 00 Brno, Czech Republic
| | - Boris Vyskot
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, CZ-612 00 Brno, Czech Republic
| | - Roman Hobza
- Department of Plant Developmental Genetics, Institute of Biophysics, Academy of Sciences of the Czech Republic, v.v.i., Kralovopolska 135, CZ-612 00 Brno, Czech Republic; Institute of Experimental Botany, Centre of the Region Haná for Biotechnological and Agricultural Research, Slechtitelu 31, CZ-78371 Olomouc, Czech Republic
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12
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Mondoni A, Orsenigo S, Donà M, Balestrazzi A, Probert RJ, Hay FR, Petraglia A, Abeli T. Environmentally induced transgenerational changes in seed longevity: maternal and genetic influence. ANNALS OF BOTANY 2014; 113:1257-63. [PMID: 24681509 PMCID: PMC4030812 DOI: 10.1093/aob/mcu046] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
BACKGROUND AND AIMS Seed longevity, a fundamental plant trait for ex situ conservation and persistence in the soil of many species, varies across populations and generations that experience different climates. This study investigates the extent to which differences in seed longevity are due to genetic differences and/or modified by adaptive responses to environmental changes. METHODS Seeds of two wild populations of Silene vulgaris from alpine (wA) and lowland (wL) locations and seeds originating from their cultivation in a lowland common garden for two generations (cA1, cL1, cA2 and cL2) were exposed to controlled ageing at 45 °C, 60 % relative humidity and regularly sampled for germination and relative mRNA quantification (SvHSP17.4 and SvNRPD12). KEY RESULTS The parental plant growth environment affected the longevity of seeds with high plasticity. Seeds of wL were significantly longer lived than those of wA. However, when alpine plants were grown in the common garden, longevity doubled for the first generation of seeds produced (cA1). Conversely, longevity was similar in all lowland seed lots and did not increase in the second generation of seeds produced from alpine plants grown in the common garden (cA2). Analysis of parental effects on mRNA seed provisioning indicated that the accumulation of gene transcripts involved in tolerance to heat stress was highest in wL, cL1 and cL2, followed by cA1, cA2 and wA. CONCLUSIONS Seed longevity has a genetic basis, but may show strong adaptive responses, which are associated with differential accumulation of mRNA via parental effects. Adaptive adjustments of seed longevity due to transgenerational plasticity may play a fundamental role in the survival and persistence of the species in the face of future environmental challenges. The results suggest that regeneration location may have important implications for the conservation of alpine plants held in seed banks.
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Affiliation(s)
- A Mondoni
- Museo delle Scienze, Corso della Scienza 3, 38123, Trento, Italy
| | - S Orsenigo
- Università di Pavia, Dipartimento di Scienze della Terra e dell'Ambiente, Via S. Epifanio 14, 27100, Pavia, Italy
| | - M Donà
- Università di Pavia, Dipartimento di Biologia e Biotecnologie, Via Ferrata 1, 27100, Pavia, Italy
| | - A Balestrazzi
- Università di Pavia, Dipartimento di Biologia e Biotecnologie, Via Ferrata 1, 27100, Pavia, Italy
| | - R J Probert
- Seed Conservation Department, Royal Botanic Gardens, Kew, Wakehurst Place, Ardingly, West Sussex RH17 6TN, UK
| | - F R Hay
- T.T. Chang Genetic Resources Center, International Rice Research Institute, DAPO Box 7777, Metro Manila, Philippines
| | - A Petraglia
- Università di Parma, Dipartimento di Bioscienze, Viale delle scienze 11/a, 43124 Parma, Italy
| | - T Abeli
- Università di Pavia, Dipartimento di Scienze della Terra e dell'Ambiente, Via S. Epifanio 14, 27100, Pavia, Italy
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13
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Zemp N, Minder A, Widmer A. Identification of internal reference genes for gene expression normalization between the two sexes in dioecious white Campion. PLoS One 2014; 9:e92893. [PMID: 24675788 PMCID: PMC3968030 DOI: 10.1371/journal.pone.0092893] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 02/26/2014] [Indexed: 11/29/2022] Open
Abstract
Quantitative real time (qRT)-PCR is a precise and efficient method for studying gene expression changes between two states of interest, and is frequently used for validating interesting gene expression patterns in candidate genes initially identified in genome-wide expression analyses, such as RNA-seq experiments. For an adequate normalisation of qRT-PCR data, it is essential to have reference genes available whose expression intensities are constant among the different states of interest. In this study we present and validate a catalogue of traditional and newly identified reference genes that were selected from RNA-seq data from multiple individuals from the dioecious plant Silene latifolia with the aim of studying gene expression differences between the two sexes in both reproductive and vegetative tissues. The catalogue contains more than 15 reference genes with both stable expression intensities and a range of expression intensities in flower buds and leaf tissues. These reference genes were used to normalize expression differences between reproductive and vegetative tissues in eight candidate genes with sex-biased expression. Our results suggest a trend towards a reduced sex-bias in sex-linked gene expression in vegetative tissues. In this study, we report on the systematic identification and validation of internal reference genes for adequate normalization of qRT-PCR-based analyses of gene expression differences between the two sexes in S. latifolia. We also show how RNA-seq data can be used efficiently to identify suitable reference genes in a wide diversity of species.
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Affiliation(s)
- Niklaus Zemp
- ETH Zurich, Institute of Integrative Biology (IBZ), Zürich, Switzerland
| | - Aria Minder
- ETH Zurich, Genetic Diversity Centre (GDC), Zürich, Switzerland
| | - Alex Widmer
- ETH Zurich, Institute of Integrative Biology (IBZ), Zürich, Switzerland
- * E-mail:
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14
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Müller K, Storchova H. Transcription of atp1 is influenced by both genomic configuration and nuclear background in the highly rearranged mitochondrial genomes of Silene vulgaris. PLANT MOLECULAR BIOLOGY 2013; 81:495-505. [PMID: 23361622 DOI: 10.1007/s11103-013-0018-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Accepted: 01/19/2013] [Indexed: 06/01/2023]
Abstract
An extraordinary variation in mitochondrial DNA sequence exists in angiosperm Silene vulgaris. The atp1 gene is flanked by very variable regions, as deduced from four completely sequenced mitochondrial genomes of this species. This diversity contributed to a highly variable transcript profile of this gene observed across S. vulgaris populations. We examined the atp1 transcript in the KOV mitochondrial genome and found three 5' ends, created most likely by the combination of transcription initiation and RNA processing. Most atp1 transcripts terminated about 70 bp upstream of the translation stop codon, which was present in only 10 % of them. Controlled crosses between a KOV mother and a geographically distant pollen donor (Krasnoyarsk, Russia) showed that nuclear background also affected atp1 transcription. The distant pollen donor introduced the factor(s) preventing the formation of a long 2,100 nt-transcript, because this long atp1 transcript reappeared in the progeny from self-crosses. The highly rearranged mitochondrial genomes with a variation in gene flanking regions make S. vulgaris an excellent model for the study of mitochondrial gene expression in plants.
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Affiliation(s)
- Karel Müller
- Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Prague, Lysolaje, 16502, Czech Republic
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15
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Käfer J, Talianová M, Bigot T, Michu E, Guéguen L, Widmer A, Žlůvová J, Glémin S, Marais GAB. Patterns of molecular evolution in dioecious and non-dioecious Silene. J Evol Biol 2012. [PMID: 23206219 DOI: 10.1111/jeb.12052] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Dioecy (i.e. having separate sexes) is a rather rare breeding system in flowering plants. Such rareness may result from a high probability of extinction in dioecious species because of less efficient dispersal and the costs of sexual selection, which are expected to harm dioecious species' survival on the long term. These handicaps should decrease the effective population size (Ne) of dioecious species, which in turn should reduce the efficacy of selection. Moreover, sexual selection in dioecious species is expected to specifically affect some genes, which will evolve under positive selection. The relative contribution of these effects is currently unknown and we tried to disentangle them by comparing sequence evolution between dioecious and non-dioecious species in the Silene genus (Caryophyllaceae), where dioecy has evolved at least twice. For the dioecious species in the section Melandrium, where dioecy is the oldest, we found a global reduction of purifying selection, while on some, male-biased genes, positive selection was found. For section Otites, where dioecy evolved more recently, we found no significant differences between dioecious and non-dioecious species. Our results are consistent with the view that dioecy is an evolutionary dead end in flowering plants, although other scenarios for explaining reduced Ne cannot be ruled out. Our results also show that contrasting forces act on the genomes of dioecious plants, and suggest that some time is required before the genome of such plants bears the footprints of dioecy.
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Affiliation(s)
- J Käfer
- Univ Lyon 1, Centre National de la Recherche Scientifique, UMR5558, Laboratoire de Biométrie et Biologie Évolutive, Villeurbanne, France.
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16
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Gupta AK, Akhtar TA, Widmer A, Pichersky E, Schiestl FP. Identification of white campion (Silene latifolia) guaiacol O-methyltransferase involved in the biosynthesis of veratrole, a key volatile for pollinator attraction. BMC PLANT BIOLOGY 2012; 12:158. [PMID: 22937972 PMCID: PMC3492160 DOI: 10.1186/1471-2229-12-158] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Accepted: 08/27/2012] [Indexed: 05/10/2023]
Abstract
BACKGROUND Silene latifolia and its pollinator, the noctuid moth Hadena bicruris, represent an open nursery pollination system wherein floral volatiles, especially veratrole (1, 2-dimethoxybenzene), lilac aldehydes, and phenylacetaldehyde are of key importance for floral signaling. Despite the important role of floral scent in ensuring reproductive success in S. latifolia, the molecular basis of scent biosynthesis in this species has not yet been investigated. RESULTS We isolated two full-length cDNAs from S. latifolia that show similarity to rose orcinol O-methyltransferase. Biochemical analysis showed that both S. latifolia guaiacol O-methyltransferase1 (SlGOMT1) &S. latifolia guaiacol O-methyltransferase2 (SlGOMT2) encode proteins that catalyze the methylation of guaiacol to form veratrole. A large Km value difference between SlGOMT1 (~10 μM) and SlGOMT2 (~501 μM) resulted that SlGOMT1 is 31-fold more catalytically efficient than SlGOMT2. qRT-PCR expression analysis showed that the SlGOMT genes are specifically expressed in flowers and male S. latifolia flowers had 3- to 4-folds higher level of GOMT gene transcripts than female flower tissues. Two related cDNAs, S. dioica O-methyltransferase1 (SdOMT1) and S. dioica O-methyltransferase2 (SdOMT2), were also obtained from the sister species Silene dioica, but the proteins they encode did not methylate guaiacol, consistent with the lack of veratrole emission in the flowers of this species. Our evolutionary analysis uncovered that SlGOMT1 and SlGOMT2 genes evolved under positive selection, whereas SdOMT1 and SdOMT2 genes show no evidence for selection. CONCLUSIONS Altogether, we report the identification and functional characterization of the gene, SlGOMT1 that efficiently catalyzes veratrole formation, whereas another copy of this gene with only one amino acid difference, SlGOMT2 was found to be less efficient for veratrole synthesis in S. latifolia.
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Affiliation(s)
- Alok K Gupta
- Institute of Systematic Botany, University of Zurich, Zurich, CH-8008, Switzerland
- ETH Zurich, Institute of Integrative Biology, Plant Ecological Genetics, Zurich, CH-8092, Switzerland
| | - Tariq A Akhtar
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Alex Widmer
- ETH Zurich, Institute of Integrative Biology, Plant Ecological Genetics, Zurich, CH-8092, Switzerland
| | - Eran Pichersky
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Florian P Schiestl
- Institute of Systematic Botany, University of Zurich, Zurich, CH-8008, Switzerland
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17
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Muyle A, Zemp N, Deschamps C, Mousset S, Widmer A, Marais GAB. Rapid de novo evolution of X chromosome dosage compensation in Silene latifolia, a plant with young sex chromosomes. PLoS Biol 2012; 10:e1001308. [PMID: 22529744 PMCID: PMC3328428 DOI: 10.1371/journal.pbio.1001308] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Accepted: 03/01/2012] [Indexed: 11/18/2022] Open
Abstract
Silene latifolia is a dioecious plant with heteromorphic sex chromosomes that have originated only ∼10 million years ago and is a promising model organism to study sex chromosome evolution in plants. Previous work suggests that S. latifolia XY chromosomes have gradually stopped recombining and the Y chromosome is undergoing degeneration as in animal sex chromosomes. However, this work has been limited by the paucity of sex-linked genes available. Here, we used 35 Gb of RNA-seq data from multiple males (XY) and females (XX) of an S. latifolia inbred line to detect sex-linked SNPs and identified more than 1,700 sex-linked contigs (with X-linked and Y-linked alleles). Analyses using known sex-linked and autosomal genes, together with simulations indicate that these newly identified sex-linked contigs are reliable. Using read numbers, we then estimated expression levels of X-linked and Y-linked alleles in males and found an overall trend of reduced expression of Y-linked alleles, consistent with a widespread ongoing degeneration of the S. latifolia Y chromosome. By comparing expression intensities of X-linked alleles in males and females, we found that X-linked allele expression increases as Y-linked allele expression decreases in males, which makes expression of sex-linked contigs similar in both sexes. This phenomenon is known as dosage compensation and has so far only been observed in evolutionary old animal sex chromosome systems. Our results suggest that dosage compensation has evolved in plants and that it can quickly evolve de novo after the origin of sex chromosomes.
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Affiliation(s)
- Aline Muyle
- Laboratoire de Biométrie et Biologie Evolutive (UMR 5558), CNRS/Université Lyon 1, Villeurbanne, France
| | - Niklaus Zemp
- Institute of Integrative Biology (IBZ), ETH Zurich, Zürich, Switzerland
| | | | - Sylvain Mousset
- Laboratoire de Biométrie et Biologie Evolutive (UMR 5558), CNRS/Université Lyon 1, Villeurbanne, France
| | - Alex Widmer
- Institute of Integrative Biology (IBZ), ETH Zurich, Zürich, Switzerland
- * E-mail: (GABM); (AW)
| | - Gabriel A. B. Marais
- Laboratoire de Biométrie et Biologie Evolutive (UMR 5558), CNRS/Université Lyon 1, Villeurbanne, France
- * E-mail: (GABM); (AW)
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18
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Schliesky S, Gowik U, Weber APM, Bräutigam A. RNA-Seq Assembly - Are We There Yet? FRONTIERS IN PLANT SCIENCE 2012; 3:220. [PMID: 23056003 PMCID: PMC3457010 DOI: 10.3389/fpls.2012.00220] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 09/05/2012] [Indexed: 05/20/2023]
Abstract
Transcriptomic sequence resources represent invaluable assets for research, in particular for non-model species without a sequenced genome. To date, the Next Generation Sequencing technologies 454/Roche and Illumina have been used to generate transcriptome sequence databases by mRNA-Seq for more than fifty different plant species. While some of the databases were successfully used for downstream applications, such as proteomics, the assembly parameters indicate that the assemblies do not yet accurately reflect the actual plant transcriptomes. Two different assembly strategies have been used, overlap consensus based assemblers for long reads and Eulerian path/de Bruijn graph assembler for short reads. In this review, we discuss the challenges and solutions to the transcriptome assembly problem. A list of quality control parameters and the necessary scripts to produce them are provided.
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Affiliation(s)
- Simon Schliesky
- Center of Excellence on Plant Sciences (CEPLAS), Institute for Plant Biochemistry, Heinrich Heine UniversityDüsseldorf, Germany
| | - Udo Gowik
- Center of Excellence on Plant Sciences (CEPLAS), Institute for Plant Developmental and Molecular Biology, Heinrich Heine UniversityDüsseldorf, Germany
| | - Andreas P. M. Weber
- Center of Excellence on Plant Sciences (CEPLAS), Institute for Plant Biochemistry, Heinrich Heine UniversityDüsseldorf, Germany
| | - Andrea Bräutigam
- Center of Excellence on Plant Sciences (CEPLAS), Institute for Plant Biochemistry, Heinrich Heine UniversityDüsseldorf, Germany
- *Correspondence: Andrea Bräutigam, Institute for Plant Biochemistry, 26.03.01.Room 32, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany. e-mail:
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19
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Amid C, Birney E, Bower L, Cerdeño-Tárraga A, Cheng Y, Cleland I, Faruque N, Gibson R, Goodgame N, Hunter C, Jang M, Leinonen R, Liu X, Oisel A, Pakseresht N, Plaister S, Radhakrishnan R, Reddy K, Rivière S, Rossello M, Senf A, Smirnov D, Ten Hoopen P, Vaughan D, Vaughan R, Zalunin V, Cochrane G. Major submissions tool developments at the European Nucleotide Archive. Nucleic Acids Res 2011; 40:D43-7. [PMID: 22080548 PMCID: PMC3245037 DOI: 10.1093/nar/gkr946] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The European Nucleotide Archive (ENA; http://www.ebi.ac.uk/ena), Europe's primary nucleotide sequence resource, captures and presents globally comprehensive nucleic acid sequence and associated information. Covering the spectrum from raw data to assembled and functionally annotated genomes, the ENA has witnessed a dramatic growth resulting from advances in sequencing technology and ever broadening application of the methodology. During 2011, we have continued to operate and extend the broad range of ENA services. In particular, we have released major new functionality in our interactive web submission system, Webin, through developments in template-based submissions for annotated sequences and support for raw next-generation sequence read submissions.
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Affiliation(s)
- Clara Amid
- European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, UK.
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20
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Sloan DB, Keller SR, Berardi AE, Sanderson BJ, Karpovich JF, Taylor DR. De novo transcriptome assembly and polymorphism detection in the flowering plant Silene vulgaris (Caryophyllaceae). Mol Ecol Resour 2011; 12:333-43. [PMID: 21999839 DOI: 10.1111/j.1755-0998.2011.03079.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Members of the angiosperm genus Silene are widely used in studies of ecology and evolution, but available genomic and population genetic resources within Silene remain limited. Deep transcriptome (i.e. expressed sequence tag or EST) sequencing has proven to be a rapid and cost-effective means to characterize gene content and identify polymorphic markers in non-model organisms. In this study, we report the results of 454 GS-FLX Titanium sequencing of a polyA-selected and normalized cDNA library from Silene vulgaris. The library was generated from a single pool of transcripts, combining RNA from leaf, root and floral tissue from three genetically divergent European subpopulations of S. vulgaris. A single full-plate 454 run produced 959,520 reads totalling 363.6 Mb of sequence data with an average read length of 379.0 bp after quality trimming and removal of custom library adaptors. We assembled 832,251 (86.7%) of these reads into 40,964 contigs, which have a total length of 25.4 Mb and can be organized into 18,178 graph-based clusters or 'isogroups'. Assembled sequences were annotated based on homology to genes in multiple public databases. Analysis of sequence variants identified 13,432 putative single-nucleotide polymorphisms (SNPs) and 1320 simple sequence repeats (SSRs) that are candidates for microsatellite analysis. Estimates of nucleotide diversity from 1577 contigs were used to generate genome-wide distributions that revealed several outliers with high diversity. All of these resources are publicly available through NCBI and/or our website (http://silenegenomics.biology.virginia.edu) and should provide valuable genomic and population genetic tools for the Silene research community.
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Affiliation(s)
- Daniel B Sloan
- Department of Biology, University of Virginia, Charlottesville, VA 22903, USA.
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