The fine-scale recombination rate variation and associations with genomic features in a butterfly

Genome Research, Год журнала: 2023, Номер 33(5), С. 810 - 823

Опубликована: Май 1, 2023

Recombination is a key molecular mechanism that has profound implications on both micro- and macroevolutionary processes. However, the determinants of recombination rate variation in holocentric organisms are poorly understood, particular Lepidoptera (moths butterflies). The wood white butterfly (

Язык: Английский

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Annelid Comparative Genomics and the Evolution of Massive Lineage-specific Genome Rearrangement in Bilaterians

Molecular Biology and Evolution, Год журнала: 2024, Номер 41(9)

Опубликована: Авг. 13, 2024

Abstract The organization of genomes into chromosomes is critical for processes such as genetic recombination, environmental adaptation, and speciation. All animals with bilateral symmetry inherited a genome structure from their last common ancestor that has been highly conserved in some taxa but seemingly unconstrained others. However, the evolutionary forces driving these differences by which they emerge have remained largely uncharacterized. Here, we analyze across phylum Annelida using 23 chromosome-level annelid genomes. We find while many lineages maintained bilaterian structure, Clitellata, group containing leeches earthworms, possesses completely scrambled develop rearrangement index to quantify extent evolution show that, compared bilaterians, earthworms among most rearranged any currently sampled species. further can be classified two distinct categories—high low rearrangement—largely influenced presence or absence, respectively, chromosome fission events. Our findings demonstrate animal variable within reveal occur both gradual, stepwise fashion, rapid, all-encompassing changes over short timescales.

Язык: Английский

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Do chromosome rearrangements fix by genetic drift or natural selection? Insights from Brenthis butterflies

Molecular Ecology, Год журнала: 2023, Номер 33(24)

Опубликована: Окт. 9, 2023

Large-scale chromosome rearrangements, such as fissions and fusions, are a common feature of eukaryote evolution. They can have considerable influence on the evolution populations, yet it remains unclear exactly how rearrangements become established eventually fix. Rearrangements could fix by genetic drift if they weakly deleterious or neutral, may instead be favoured positive natural selection. Here, we compare genome assemblies three closely related Brenthis butterfly species characterize complex history fission fusion rearrangements. An inferred demographic these suggests that became fixed in populations with large long-term effective size (N

Язык: Английский

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GC Content Across Insect Genomes: Phylogenetic Patterns, Causes and Consequences

Journal of Molecular Evolution, Год журнала: 2024, Номер 92(2), С. 138 - 152

Опубликована: Март 15, 2024

Abstract The proportions of A:T and G:C nucleotide pairs are often unequal can vary greatly between animal species along chromosomes. causes consequences this variation incompletely understood. recent release high-quality genome sequences from the Darwin Tree Life other large-scale projects provides an opportunity for GC heterogeneity to be compared across a large number insect species. Here we analyse content chromosomes, within protein-coding genes codons, 150 four holometabolous orders: Coleoptera, Diptera, Hymenoptera, Lepidoptera. We find that have higher than average, Lepidoptera generally three orders examined. is in small chromosomes most species, but pattern less consistent orders. also increases towards subtelomeric regions Coleoptera Two Bombylius major B. discolo r, very atypical genomes with ubiquitous increase AT content, especially at third codon positions. Despite dramatic AT-biased usage, no evidence has driven divergent protein evolution. argue landscape Lepidoptera, Diptera influenced by GC-biased gene conversion, strongest some outlier taxa affected drastically counteracting processes.

Язык: Английский

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Meiotic drive against chromosome fusions in butterfly hybrids

Chromosome Research, Год журнала: 2024, Номер 32(2)

Опубликована: Май 4, 2024

Abstract Species frequently differ in the number and structure of chromosomes they harbor, but individuals that are heterozygous for chromosomal rearrangements may suffer from reduced fitness. Chromosomal like fissions fusions can hence serve as a mechanism speciation between incipient lineages, their evolution poses paradox. How get fixed populations if heterozygotes have fitness? One solution is this process predominantly occurs small isolated populations, where genetic drift override natural selection. However, fixation also more likely novel rearrangement favored by transmission bias, such meiotic drive. Here, we investigate distortion hybrids two wood white ( Leptidea sinapis ) butterfly with extensive karyotype differences. Using data different crossing experiments, uncover there bias favoring ancestral state derived fusions, result shows chromosome actually fix despite being counteracted This means drive not only promote runaway speciation, it be conservative force acting against karyotypic change reproductive isolation. Based on our results, suggest mechanistic model why fusion mutations opposed discuss factors contributing to Lepidoptera.

Язык: Английский

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Temporal dynamics of faster neo-Z evolution in butterflies

Evolution, Год журнала: 2024, Номер 78(9), С. 1554 - 1567

Опубликована: Май 30, 2024

The faster-Z/X hypothesis predicts that sex-linked genes should diverge faster than autosomal genes. However, studies across different lineages have shown mixed support for this effect. So far, most analyses focused on old and well-differentiated sex chromosomes, but less is known about the divergence of more recently acquired neo-sex chromosomes. In Lepidoptera (moths butterflies), Z-autosome fusions are frequent, evolutionary dynamics neo-Z chromosomes not been explored in detail. Here, we analyzed faster-Z effect Leptidea sinapis, a butterfly with three Z We show stepwise, resulting strata differentiation masculinization. While all showed evidence effect, selection youngest chromosome (Z3) appears to hampered by largely intact, homologous neo-W chromosome. intermediately aged (Z2), which lacks W gametologs, fewer constraints, particularly fast evolution. Our results therefore can constitute temporary hot-spots adaptation divergence. underlying likely causally linked shifts selective evolution gene expression, degeneration W-linked gametologs gradually expose Z-linked selection.

Язык: Английский

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Chromosomal fusions and large-scale inversions are key features for adaptation in Arctic codfish species

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Июнь 28, 2024

Abstract The evolutionary impact of structural variants, such as chromosomal inversions, is well documented, especially for their role in local adaptation high gene flow systems. However, the other genomic rearrangements like fusions, fissions, and translocations still relatively unexplored. Here we present six chromosome-level Gadid reference genomes non-migratory Atlantic cod ( Gadus morhua ) i.e., Norwegian coastal (NCC), haddock (Melanogrammus aeglefinus), burbot Lota lota ), European hake Merluccius merluccius two keystone Arctic codfishes: polar Boreogadus saida Arctogadus glacialis ). Within a comparative genomics framework, uncovered several lineage-specific resulting reduced number chromosomes compared to ancestral state cold-water adapted codfishes. identified fusions were not homologous, indicating that they originate from independent events. Additionally, partly overlapping inversions between species detected. Using smaller population dataset, degree conservation some (including breakpoint regions), suggesting these regions are under selection, potentially importance. With use genome assemblies, demonstrate how large reorganizations likely play important roles speciation processes thus, particular freezing environmental conditions. Moreover, observe massive rearrangement events can take place across short time scales.

Язык: Английский

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Centromere diversity and its evolutionary impacts on plant karyotypes and plant reproduction

New Phytologist, Год журнала: 2025, Номер 245(5), С. 1879 - 1886

Опубликована: Янв. 6, 2025

Summary Karyotype changes are a formidable evolutionary force by directly impacting cross‐incompatibility, gene dosage, genetic linkage, chromosome segregation, and meiotic recombination landscape. These often arise spontaneously commonly detected within plant lineages, even between closely related accessions. One element that can influence drastic karyotype after only one (or few) generations is the alteration of centromere position, number, distribution, or its strength. Here, we briefly explore how these different configurations result in rearrangements, reproduction recombination.

Язык: Английский

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Evolution of Hybrid Inviability Associated With Chromosome Fusions

Molecular Ecology, Год журнала: 2025, Номер unknown

Опубликована: Фев. 3, 2025

ABSTRACT Chromosomal rearrangements, such as inversions, have received considerable attention in the speciation literature due to their hampering effects on recombination. Less is known about how other chromosome fissions and fusions, can affect evolution of reproductive isolation. Here, we use crosses between populations wood white butterfly ( Leptidea sinapis ) with different karyotypes identify genomic regions associated hybrid inviability. We map inviability candidate loci by contrasting allele frequencies F 2 hybrids that survived until adult stage individuals same cohort succumbed incompatibilities. Hybrid high genetic differentiation parental populations, reduced recombination rates, are enriched near fusions. By analysing sequencing coverage, exclude aneuploidies a direct link Instead, our results point an indirect relationship possibly related fused chromosomes. Thus, postzygotic isolation chromosomal providing crucial empirical evidence for idea number differences taxa contribute speciation.

Язык: Английский

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Genomic Monitoring of a Reintroduced Butterfly Uncovers Contrasting Founder Lineage Survival

Evolutionary Applications, Год журнала: 2025, Номер 18(2)

Опубликована: Фев. 1, 2025

Genetic factors can have a major influence on both short- and long-term success of reintroductions. Genomic monitoring give range insights into the early life reintroduced population ultimately help to avoid wasting limited conservation resources. In this study, we characterise genetic diversity Carterocephalus palaemon (Chequered Skipper butterfly) in England with respect spatial structure source populations south Belgium. We aim evaluate reintroduction, including effectiveness donor sampling strategy, assess vulnerabilities that may affect population's future. also use an isolation-by-distance approach make quantitative inferences about dispersal, explore covariance between host mitochondrial Wolbachia genomes. find that, four generations following initial release, population, founded by 66 wild-caught adults, has effective size c. 33, yet retained similar levels genomic heterozygosity those subpopulations Belgium shows low inbreeding. However, restricted number founders variance reproductive among surviving families resulted higher level kinship, likely result somewhat rates inbreeding Furthermore, there is distinct split two landscapes Belgium, all evidence suggests descended from only one these (called Fagne). discuss potential causes behind results, whether strains are causing incompatibility clades. conclude conservative strategy for any further translocations would prefer Fagne sites as sources because strong their ability survive. our results warrant investigation reasons divergence found

Язык: Английский

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