Sex chromosome turnover plays an important role in the maintenance of barriers to post-speciation introgression in willows

Evolution Letters, Journal Year: 2024, Volume and Issue: 8(4), P. 467 - 477

Published: March 28, 2024

Abstract Almost all species in the genus Salix (willow) are dioecious and willows have variable sex-determining systems, role of this variation maintaining barriers is relatively untested. We first analyzed sex determination systems (SDS) two species, cardiophylla interior, whose positions phylogeny make them important for understanding a chromosome turnover that has been detected their relatives, changed system from male (XX/XY) to female (ZW/ZZ) heterogamety. show both heterogamety, with sex-linked regions (SLRs) on 15 (termed 15XY system). The SLRs occupy 21.3% 22.8% entire reference chromosome, respectively. By constructing phylogenetic trees, we determined known SDSs. Reconstruction ancestral SDS character states revealed likely state willows. Turnovers 15ZW 7XY contributed early speciation gave rise major groups Vetrix clades. Finally, tested introgression among trees based autosomes separately. Frequent was observed 15XY, 15ZW, autosomes, contrast SLR datasets, which showed less introgression, particular no gene flow between species. argue that, although turnovers willow may not create complete reproductive barriers, evolution plays roles preventing boundaries.

Language: Английский

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Evidence for widespread selection in shaping the genomic landscape during speciation of Populus

Molecular Ecology, Journal Year: 2020, Volume and Issue: 29(6), P. 1120 - 1136

Published: Feb. 18, 2020

Abstract Increasing our understanding of how evolutionary processes drive the genomic landscape variation is fundamental to a better consequences speciation. However, genome‐wide patterns within‐ and between‐ species have not been fully investigated in most forest tree despite their global ecological economic importance. Here, we use whole‐genome resequencing data from four Populus spanning speciation continuum reconstruct demographic histories investigate diversity divergence within between species. Using trichocarpa as an outgroup species, further infer genealogical relationships estimate extent ancient introgression among three aspen ( tremula , davidiana tremuloides ) throughout genome. Our results show substantial these along genomes with this being strongly predicted by local recombination rates density functional elements. This implies that interaction recurrent selection intrinsic features has dramatically sculpted over long periods time. In addition, findings provide evidence that, apart background selection, recent positive long‐term balancing also crucial components shaping during process.

Language: Английский

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Double drives and private alleles for localised population genetic control

PLoS Genetics, Journal Year: 2021, Volume and Issue: 17(3), P. e1009333 - e1009333

Published: March 23, 2021

Synthetic gene drive constructs could, in principle, provide the basis for highly efficient interventions to control disease vectors and other pest species. This efficiency derives part from leveraging natural processes of dispersal flow spread construct its impacts one population another. However, sometimes (for example, with invasive species) only specific populations are need control, on non-target would be undesirable. Many designs use nucleases that recognise cleave genomic sequences, way restrict their exploit sequence differences between target populations. In this paper we propose model a series low threshold double suppression, each consisting two constructs, imposing reproductive load inserted into differentiated locus controlling first. Simple deterministic, discrete-generation computer simulations used assess alternative designs. We find simplest significantly more robust pre-existing cleavage resistance at than single designs, complex incorporating sex ratio distortion can still, even allowing successful when is neutral there up 50% population. Similar also replacement, similar benefits. A analysis CRISPR PAM sites island mainland malaria mosquito Anopheles gambiae indicates differentiation needed our methods work exist nature. Double drives should considered but localised genetic some

Language: Английский

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Recovery from hybrid breakdown reveals a complex genetic architecture of mitonuclear incompatibilities

Molecular Ecology, Journal Year: 2021, Volume and Issue: 30(23), P. 6403 - 6416

Published: May 18, 2021

Reproductive isolation is often achieved when genes that are neutral or beneficial in their genomic background become functionally incompatible a foreign background, causing inviability, sterility other forms of low fitness hybrids. Recent studies suggest mitonuclear interactions among the initial incompatibilities to evolve at early stages population divergence across taxa. Yet, architecture has rarely been elucidated. We employ an experimental evolution approach starting with low-fitness F2 interpopulation hybrids copepod Tigriopus californicus, which frequencies compatible and nuclear alleles change response alternative mitochondrial background. After about nine generations, we observe generalized increase size survivorship, suggesting efficiency selection against maladaptive phenotypes. Whole genome sequencing evolved populations showed some consistent allele frequency changes three replicates each reciprocal cross, but markedly different patterns between backgrounds. In only few regions (~6.5% genome), same parental was overrepresented irrespective About 33% divergent selection, location these strongly differing 87% 89% regions, dominant matched associated co-adaptation. These results have complex polygenic differs populations, potentially generating genome-wide barriers gene flow closely related

Language: Английский

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Patterns of Genomic Differentiation in the Drosophila nasuta Species Complex

Molecular Biology and Evolution, Journal Year: 2019, Volume and Issue: 37(1), P. 208 - 220

Published: Sept. 15, 2019

Abstract The Drosophila nasuta species complex contains over a dozen recently diverged that are distributed widely across South-East Asia, and which shows varying degrees of pre- postzygotic isolation. Here, we assemble high-quality genome for D. albomicans using single-molecule sequencing chromatin conformation capture, draft genomes 11 additional 67 individuals the clade, to infer phylogeny patterns genetic diversity in this group. Our assembly recovers entire chromosomes, date origin radiation ∼2 Ma. Despite low levels overall differentiation, most or subspecies show clear clustering into their designated taxonomic groups population genetics phylogenetic methods. Local evolutionary history is heterogeneous genome, differs between autosomes X chromosome sulfurigaster subgroup, likely due autosomal introgression. study establishes as promising model system further characterize evolution isolation clade.

Language: Английский

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