Diversity and Determinants of Meiotic Recombination Landscapes

Trends in Genetics, Journal Year: 2019, Volume and Issue: 35(5), P. 359 - 370

Published: April 1, 2019

Language: Английский

---

Diversity and determinants of recombination landscapes in flowering plants

PLoS Genetics, Journal Year: 2022, Volume and Issue: 18(8), P. e1010141 - e1010141

Published: Aug. 30, 2022

During meiosis, crossover rates are not randomly distributed along the chromosome and their location may have a strong impact on functioning evolution of genome. To date, broad diversity recombination landscapes among plants has rarely been investigated formal comparative genomic approach is still needed to characterize assess determinants species chromosomes. We gathered genetic maps genomes for 57 flowering plant species, corresponding 665 chromosomes, which we estimated large-scale landscapes. found that number per spans limited range (between one five/six) whatever genome size, there no single relationship across between map length size. Instead, general relative size chromosomes rate, while absolute constrains basal rate each species. At level, identified two main patterns (with few exceptions) proposed conceptual model explaining broad-scale distribution crossovers where both telomeres centromeres play role. These correspond globally underlying gene distribution, affects how efficiently genes shuffled at meiosis. results raised new questions only but also

Language: Английский

---

Chromosome Fissions and Fusions Act as Barriers to Gene Flow betweenBrenthisFritillary Butterflies

Molecular Biology and Evolution, Journal Year: 2023, Volume and Issue: 40(3)

Published: Feb. 22, 2023

Abstract Chromosome rearrangements are thought to promote reproductive isolation between incipient species. However, it is unclear how often, and under what conditions, fission fusion act as barriers gene flow. Here we investigate speciation two largely sympatric fritillary butterflies, Brenthis daphne ino. We use a composite likelihood approach infer the demographic history of these species from whole-genome sequence data. then compare chromosome-level genome assemblies individuals each identify total nine chromosome fissions fusions. Finally, fit model where effective population sizes migration rate vary across genome, allowing us quantify effects on isolation. show that chromosomes involved in experienced less since onset divergence genomic regions near rearrangement points have further reduction rate. Our results suggest evolution multiple B. ino populations, including alternative fusions same chromosomes, resulted Although unlikely be only processes led this study shows can directly may when karyotypes evolve quickly.

Language: Английский

---

The origin and evolution of sex chromosomes, revealed by sequencing of the Silene latifolia female genome

Current Biology, Journal Year: 2023, Volume and Issue: 33(12), P. 2504 - 2514.e3

Published: June 1, 2023

White campion (Silene latifolia, Caryophyllaceae) was the first vascular plant where sex chromosomes were discovered. This species is a classic model for studies on due to presence of large, clearly distinguishable X and Y that originated de novo about 11 million years ago (mya), but lack genomic resources this relatively large genome (∼2.8 Gb) remains significant hurdle. Here we report S. latifolia female assembly integrated with sex-specific genetic maps species, focusing their evolution. The analysis reveals highly heterogeneous recombination landscape strong reduction in rate central parts all chromosomes. Recombination chromosome meiosis primarily occurs at very ends, over 85% length located massive (∼330 Mb) gene-poor, rarely recombining pericentromeric region (Xpr). results indicate non-recombining (NRY) initially evolved small (∼15 Mb), actively end q-arm, possibly as result inversion nascent chromosome. NRY expanded 6 mya via linkage between Xpr sex-determining region, which may have been caused by expanding suppression These findings shed light origin yield assist ongoing future investigations into

Language: Английский

---

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

Genome Research, Journal Year: 2023, Volume and Issue: 33(5), P. 810 - 823

Published: May 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 (

Language: Английский

---

Meiotic recombination dynamics in plants with repeat-based holocentromeres shed light on the primary drivers of crossover patterning

Nature Plants, Journal Year: 2024, Volume and Issue: 10(3), P. 423 - 438

Published: Feb. 9, 2024

Abstract Centromeres strongly affect (epi)genomic architecture and meiotic recombination dynamics, influencing the overall distribution frequency of crossovers. Here we show how is regulated distributed in holocentric plant Rhynchospora breviuscula , a species with diffused centromeres. Combining immunocytochemistry, chromatin analysis high-throughput single-pollen sequencing, discovered that crossover distally biased, sharp contrast to hundreds centromeric units features. Remarkably, found crossovers were abolished inside but not their proximity, indicating absence canonical centromere effect. We further propose telomere-led synapsis homologues feature best explains observed landscape. Our results hint at primary influence mechanistic features pairing rather than organization determining biased R. whereas centromeres (epi)genetic properties only positioning locally.

Language: Английский

---

A macroevolutionary role for chromosomal fusion and fission in Erebia butterflies

Science Advances, Journal Year: 2024, Volume and Issue: 10(16)

Published: April 17, 2024

The impact of large-scale chromosomal rearrangements, such as fusions and fissions, on speciation is a long-standing conundrum. We assessed whether bursts change in chromosome numbers resulting from fusion or fission are related to increased rates Erebia , one the most species-rich karyotypically variable butterfly groups. established genome-based phylogeny used state-dependent birth-death models infer trajectories karyotype evolution. demonstrated that anagenetic changes (i.e., along phylogenetic branches) exceed cladogenetic at events), but, when occur, they mostly associated with fissions rather than fusions. found relative importance differs among clades different ages especially younger, more diverse clades, frequently changes. Overall, our results imply have contrasting macroevolutionary roles rearrangements species diversification.

Language: Английский

---

Selection can favor a recombination landscape that limits polygenic adaptation

Molecular Biology and Evolution, Journal Year: 2025, Volume and Issue: 42(1)

Published: Jan. 1, 2025

Abstract Modifiers of recombination rates have been described but the selective pressures acting on them and their effect adaptation to novel environments remain unclear. We performed experimental evolution in nematode Caenorhabditis elegans using alternative rec-1 alleles modifying position meiotic crossovers along chromosomes without detectable direct fitness effects. show that a environment is impaired by allele decreases genomic regions containing variation. However, impairs indirectly favored selection, because it increases reduces associations among beneficial deleterious variation located its chromosomal vicinity. These results validate theoretical expectations about suggest genome-wide polygenic little consequence indirect selection rate modifiers.

Language: Английский

---

Variation in Recombination Rate Is Shaped by Domestication and Environmental Conditions in Barley

Molecular Biology and Evolution, Journal Year: 2019, Volume and Issue: 36(9), P. 2029 - 2039

Published: June 11, 2019

Abstract Meiotic recombination generates genetic diversity upon which selection can act. Recombination rates are highly variable between species, populations, individuals, sexes, chromosomes, and chromosomal regions. The underlying mechanisms controlled at the epigenetic level show plasticity toward environment. Environmental may be divided into short- long-term responses. We estimated in natural populations of wild barley domesticated landraces using a population genetics approach. analyzed landscapes high resolution. In barley, found more interstitial chromosome regions contrast to distal barley. Among subpopulations variation effective rate is correlated with temperature, isothermality, solar radiation nonlinear manner. A positive linear correlation was annual precipitation. discuss our findings respect how environment might shape populations. Higher subjected specific environmental conditions could means maintain fitness strictly inbreeding species.

Language: Английский

---

Mandarin fish (Sinipercidae) genomes provide insights into innate predatory feeding

Communications Biology, Journal Year: 2020, Volume and Issue: 3(1)

Published: July 9, 2020

Abstract Mandarin fishes (Sinipercidae) are piscivores that feed solely on live fry. Unlike higher vertebrates, teleosts exhibit feeding behavior driven mainly by genetic responses, with no modification learning from parents. could serve as excellent model organisms for studying behavior. We report a long-read, chromosomal-scale genome assembly Siniperca chuatsi and assemblies kneri , scherzeri Coreoperca whiteheadi . Positive selection analysis revealed rapid adaptive evolution of genes related to predatory feeding/aggression, growth, pyloric caeca euryhalinity. Very few gill rakers observed in mandarin fishes; analogously, we found zebrafish deficient edar had raker loss phenotype more habit, reduced intake zooplankton but increased prey fish. Higher expression bmp4 which inhibit development through binding Xvent-1 site upstream may cause

Language: Английский

---