Ploidy as a leaky reproductive barrier: mechanisms, rates and evolutionary significance of interploidy gene flow

Annals of Botany, Journal Year: 2024, Volume and Issue: unknown

Published: June 13, 2024

Abstract Background Whole-genome duplication (polyploidization) is a dominant force in sympatric speciation, particularly plants. Genome doubling instantly poses barrier to gene flow owing the strong crossing incompatibilities between individuals differing ploidy. The strength of barrier, however, varies from species and recent genetic investigations revealed cases rampant interploidy introgression multiple ploidy-variable species. Scope Here, we review novel insights into frequency natural systems summarize underlying mechanisms promoting flow. Field surveys, occasionally complemented by experiments, suggest frequent opportunities for flow, direction diploid tetraploid, (higher) polyploids. However, scarcity accompanying population evidence virtual lack integration these approaches leave levels realized nature largely unknown. Finally, discuss potential consequences genome permeability on polyploid speciation adaptation highlight avenues that have just recently been opened very first genomic studies Standing stark contrast with rapidly accumulating evolutionary importance homoploid introgression, similar are yet be documented. Conclusions genomics era provides opportunity re-evaluate role adaptation. To achieve this goal, interdisciplinary bordering ecology genetics needed.

Language: Английский

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The Winner Takes It All: a single genotype of Kalanchoe ×houghtonii is a global invader

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 7, 2025

Abstract Background and Aims Invasive alien plant species pose a global challenge, their impact is amplified by globalisation the accelerating pace of climate change. In mild-climate regions, drought-tolerant invasive plants showing broad environmental tolerance have competitive advantage. One example Kalanchoe × houghtonii (Crassulaceae), popularly known as “mother millions”. It hybrid resulting from interploid cross between K. daigremontiana delagoensis , both native to Madagascar. propagated an ornamental plant, has emerged invader in less than century. Four morphotypes this been identified, with different ploidy levels varying capacities. Here we aim investigate genomic variability behind invasion success . Methods We sampled 57 accessions houghtonii, daigremontiana, closely related taxa, including old herbarium materials, all over world. analysed genome size, chromosome numbers, sequenced whole genome, complete plastome sequence each accession, studied diversity ribosomal RNA genes. also performed detailed phylogenomic study using nuclear BUSCO Key Results Our reveals genetic cytogenetic morphotypes, shows that single tetraploid genotype (morphotype A) dominates populations, emerging first reported clonal capable worldwide colonisation. Morphotype A striking uniformity, high phenotypic plasticity, extremely rates vegetative reproduction, representing “general-purpose genotype”. Conclusions The astonishing reproductive capacity, adaptability speed at which colonising new regions spread highlight importance understanding hybridisation polyploidy ecosystems. findings call for need risk assessments before developing hybrids breeding may exhibit characteristics.

Language: Английский

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Genomic basis of adaptation to serpentine soil in two Alyssum species shows convergence with Arabidopsis across 20 million years of divergence

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 28, 2025

Abstract Background and Aims Serpentine outcrops, characterized by low nutrient availability, high heavy metal concentrations, propensity to drought, island-like distributions, offer valuable systems study parallelisms in repeated adaptation extreme environments. While shared phenotypic manifestation of serpentine environments has been investigated many species, it is still unclear whether there may be a common genetic basis underlying such responses. Here we assess local soil infer the parallel signatures two thus far unexplored closely related Alyssum gmelinii spruneri (Brassicaceae). Then measure gene- function-level convergence with previously explored Arabidopsis arenosa , reveal candidate adaptive strategies within Brassicaceae. Methods We tested for using reciprocal substrate-transplant experiment A. . Then, after assembling reference genome, generated population-level sequencing data four population pairs performed genome scans directional selection genes Finally, compared gene lists those inferred similar experiments used protein-protein interaction networks discern functional adaptation. Key Results Independent colonization populations associated footprints on ion transport homeostasis, water uptake, life-history traits germination reproduction. Reciprocal transplant demonstrated that adapted plants germinate sooner exhibit better growth conditions while excluding metals increasing Ca uptake their tissues. significant fraction molecular pathways Conclusions show multi-factorial challenge imposed involves key are not only between but also Brassicaceae tribes ∼20 Mya divergence.

Language: Английский

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Sexual selection drives the speciation of lineages with contrasting mating systems

Current Biology, Journal Year: 2025, Volume and Issue: unknown

Published: April 1, 2025

Repeated shifts in ecological strategies often lead to consistent speciation patterns across phylogenies. One example is the transition from outcrossing self-fertilization plants, which generally results reproductive isolation of incipient selfing lineages. However, evolutionary mechanisms driving their remain poorly understood. In this study, we investigate hybridization rate and barriers gene flow between recently evolved lineage Capsella rubella its ancestor C. grandiflora. Through a survey sympatric populations Greece, found that despite coexisting same habitats, two species rarely form viable hybrids. Our investigation into underlying revealed differences intensity sexual selection lineages promote significant prezygotic isolation, with strength depending on direction flow. Traits enhance male competitiveness outcrossers decrease chance being pollinated by selfers, lowering rate, but simultaneously increase likelihood selfers outcrossers. Selfers nevertheless limit through rapid efficient mechanisms. Finally, postzygotic barriers, such as hybrid incompatibilities likely driven parental conflict intensity,1 also contribute Therefore, efficiency appear be key drivers following mating system changes, possibly explaining recurrent plant evolution.

Language: Английский

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Variant calling in polyploids for population and quantitative genetics

Applications in Plant Sciences, Journal Year: 2024, Volume and Issue: 12(4)

Published: July 1, 2024

Abstract Advancements in genome assembly and sequencing technology have made whole sequence (WGS) data reference genomes accessible to study polyploid species. Compared popular reduced‐representation approaches, the genome‐wide coverage greater marker density provided by WGS can greatly improve our understanding of species biology. However, biological features that make interesting also pose challenges read mapping, variant identification, genotype estimation. Accounting for characteristics calling like allelic dosage uncertainty, homology between subgenomes, variance chromosome inheritance mode reduce errors. Here, I discuss where potential solutions be integrated into a standard pipeline.

Language: Английский

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Polyploids broadly generate novel haplotypes from trans-specific variation in Arabidopsis arenosa and Arabidopsis lyrata

PLoS Genetics, Journal Year: 2024, Volume and Issue: 20(12), P. e1011521 - e1011521

Published: Dec. 23, 2024

Polyploidy, the result of whole genome duplication (WGD), is widespread across tree life and often associated with speciation adaptability. It thought that adaptation in autopolyploids (within-species polyploids) may be facilitated by increased access to genetic variation. This variation sourced from gene flow sister diploids new other tetraploid lineages, as well mutational targets provided doubled DNA content. Here, we deconstruct detail origins haplotypes displaying strongest selection signals established, successful autopolyploids, Arabidopsis lyrata arenosa . We see strong signatures 17 genes implied meiosis, cell cycle, transcription all four autotetraploid lineages present our expanded sampling 983 sequenced genomes. Most prominent results finding tetraploid-characteristic most robust were completely absent diploid sisters. In contrast, fine-scaled variant ‘mosaics’ tetraploids originated highly diverse evolutionary sources. These include novel reassortments trans-specific polymorphism diploids, mutations, tetraploid-specific inter-species hybridization–a pattern line broad-scale acquisition reshuffling potentially adaptive tetraploids.

Language: Английский

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Novel reassortments of variation underlie repeated adaptation to whole genome duplication in two outcrossing Arabidopsis species

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Jan. 13, 2023

Abstract Polyploidy, the result of whole genome duplication (WGD), is widespread across tree life and often associated with speciation or adaptability. It thought that adaptation in autopolyploids (within-species polyploids) may be facilitated by increased access to genetic variation. This variation sourced from gene flow sister diploids new other tetraploid lineages, as well mutational targets provided doubled DNA content. Here we deconstruct origins haplotype blocks displaying strongest selection signals established, successful autopolyploids, Arabidopsis lyrata arenosa . We see strong signatures 17 genes implied meiosis, cell cycle, transcription all four autotetraploid lineages present our expanded sampling 983 sequenced genomes. Most prominent results finding tetraploid-characteristic most robust were completely absent diploid sisters. In contrast, fine-scaled variant mosaics tetraploids originated highly diverse evolutionary sources. These include novel reassortments trans-specific polymorphism diploids, mutations, tetraploid-specific inter-species hybridization. speculate this broad-scale allele acquisition re-shuffling enabled autotetraploids rapidly adapt challenges inherent WGD, further promote their environmental challenges. Lay summary duplication, adaptation. To fuel remarkable adaptations, polyploids maintain adaptive alleles more readily than diploids. identify repeated on are mediate two species. found blocks, exhibiting selection, never relatives. Instead, these made forged multiple allelic hypothesize helped process caused increase – also help them environments.

Language: Английский

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Variant calling in polyploids for population and quantitative genetics

Published: March 15, 2024

Advancements in genome assembly and sequencing technology have made whole sequence (WGS) data reference genomes accessible to study polyploid species. The genome-wide coverage greater marker density provided by WGS data, compared popular reduced-representation approaches, can greatly improve our understanding of species biology. However, biological features that make interesting also pose challenges read mapping, variant identification, genotype estimation. Accounting for characteristics, like allelic dosage uncertainty, homology between subgenomes, variance chromosome inheritance mode, calling reduce errors. Here, I discuss the where potential solutions be integrated into a standard pipeline.

Language: Английский

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