Genetic differentiation in the MAT-proximal region is not sufficient for suppressing recombination in Podospora anserina DOI Open Access
Pierre Grognet, Robert Debuchy, Tatiana Giraud

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 7, 2024

ABSTRACT Recombination is advantageous over the long-term, as it allows efficient selection and purging deleterious mutations. Nevertheless, recombination suppression has repeatedly evolved in sex chromosomes mating-type chromosomes. The evolutionary causes for proximal mechanisms preventing crossing overs are still poorly understood. Several hypotheses have recently been suggested based on theoretical models, particular, that divergence could accumulate neutrally around a sex-determining region reduce rates, self-reinforcing process foster progressive extension of suppression. ascomycete fungus Podospora anserina an excellent model investigating these questions. A 0.8 Mb locus non-recombining, despite being collinear between two mating types. This mostly selfing, so strains highly homozygous, except non-recombining displays differentiation Here, we generated mutant to test hypothesis sequence alone responsible cessation. We replaced mat- idiomorph by mat+ idiomorph, obtain strain sexually compatible with reference isogenic this MAT -proximal region. Crosses showed was suppressed strains, indicating other than inversions or mere fungus. finding suggests selective likely acted suppressing recombination, neutral does not seem hold, at least ARTICLE SUMMARY In many organisms, observed locus. , within 800kb natural genome mating-types, displaying heterozygosity. To determine if heterozygosity can be lack were engineered isogenic, including inhibition persisted, cause Our study provides interesting insight molecular inhibition.

Language: Английский

Dynamic evolution of a sex-linked region DOI Creative Commons
Xiaomeng Mao, Nima Rafati, Christian Tellgren‐Roth

et al.

Research Square (Research Square), Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 10, 2025

Abstract Background Sex chromosomes often evolve exceptionally fast and degenerate after recombination arrest. However, the underlying evolutionary processes are under persistent debate, particularly whether or not arrest evolves in a stepwise manner how switches sex determination genes contribute to chromosome evolution. Here, we study dioecious plant genus Salix with high turnover of chromosomes. Results We identified Z W sex-linked regions (~ 8 Mb) on 15 dwarf willow Salix herbacea using new haplotype-resolved assembly. The region harboured large (5 embedded inversion. Analyses synteny other species, sequence divergence between degeneration suggest that inversion recently incorporated pseudoautosomal sequences into region, extending its length nearly three-fold. W-hemizygous exclusively contained seven pairs inverted partial repeats male essential floral identity gene PISTILLATA, suggesting possible PISTILLATA suppression mechanism by interfering RNA females. Such pseudogenes were also found species ZW but those XY determination. Conclusions Our provides rare compelling direct support for long-standing theory reduction mediated inversions suggests Salicaceae family is associated switch gene.

Language: Английский

Citations

0
Repetitive DNAs and differentiation of the ZZ/ZW sex chromosome system in the combtail fish Belontia hasselti (Perciformes: Osphronemidae) DOI Creative Commons
Alan Moura de Oliveira, Geize Aparecida Deon, Alexandr Sember

et al.

BMC Ecology and Evolution, Journal Year: 2025, Volume and Issue: 25(1)

Published: March 18, 2025

Abstract Background Java combtail fish Belontia hasselti (Cuvier, 1831), a member of the Osphronemidae family, inhabits lakes and rivers throughout Southeast Asia Sri Lanka. Previous cytogenetic research revealed it possesses diploid chromosome number 48 chromosomes with female-heterogametic ZZ/ZW sex system, where W is distinguishable as only metacentric element in complement. Female-heterogametic systems seem to be otherwise surprisingly rare highly diverse order Perciformes and, therefore, B. provides an important comparative model evolutionary studies this teleost lineage. To examine level differentiation contribution repetitive DNAs process we combined bioinformatic analyses chromosomal mapping selected DNA classes, genomic hybridization. Results By providing first satellitome study Perciformes, herein identified 13 satellite monomers , suggesting very low diversity satDNA species. Using fluorescence situ hybridization, detectable clusters on for four monomers. Together two mapped microsatellite motifs, repeats primarily accumulated autosomes, no distinct located chromosomes. Comparative hybridization showed region female-specific or enriched chromosome. Telomeric terminated all chromosomes, additional interstitial sites were detected. Conclusion These data collectively indicate degree despite their considerable heteromorphy. Possible mechanisms that may underlie pattern are discussed.

Language: Английский

Citations

0
Genetic differentiation in the MAT-proximal region is not sufficient for suppressing recombination in Podospora anserina DOI Creative Commons
Pierre Grognet, Robert Debuchy, Tatiana Giraud

et al.

G3 Genes Genomes Genetics, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 24, 2025

Recombination is advantageous over the long-term, as it allows efficient selection and purging deleterious mutations. Nevertheless, recombination suppression has repeatedly evolved in sex mating-type chromosomes. The evolutionary causes for proximal mechanisms preventing crossing overs are poorly understood. Several hypotheses have recently been suggested based on theoretical models, particular that divergence could accumulate neutrally around a sex-determining region reduce rates, self-reinforcing process foster progressive extension of suppression. We used ascomycete fungus Podospora anserina investigating these questions: 0.8 Mbp its locus non-recombining, despite being collinear between two mating types. This mostly selfing, resulting highly homozygous individuals, except non-recombining displays differentiation Here, we test hypothesis sequence alone responsible cessation. replaced mat- idiomorph by mat+ idiomorph, to obtain strain sexually compatible with reference isogenic this MAT-proximal region. Crosses showed was still suppressed mutant strains, indicating other than inversions or mere fungus. finding suggests selective likely acted suppressing recombination, spread epigenetic marks, neutral model nucleotide does not seem hold P. anserina.

Language: Английский

Citations

0
Sex Chromosome Dosage Compensation in Insects DOI Creative Commons
Xingcheng Xie, Yakun Zhang,

Hongli Peng

et al.

Insects, Journal Year: 2025, Volume and Issue: 16(2), P. 160 - 160

Published: Feb. 4, 2025

Dosage compensation (DC) is of crucial importance in balancing the sex-linked gene expression between males and females. It serves to guarantee that proteins or other enzymatic products encoded by sex chromosome exhibit quantitative parity two genders. During evolutionary process achieving dose compensation, insects have developed a wide variety mechanisms. There exist primary modes dosage mechanisms, including up-regulation heterogametic chromosomes heterogamety down-regulation homogametic homogamety. Although extensive investigations been conducted on model insects, many questions still remain unresolved. Meanwhile, research non-model attracting increasing attention. This paper systematically summarizes current advances field insect with respect its types The principal involved this study include Drosophila melanogaster, Tribolium castaneum, Bombyx mori, lepidopteran insects. analyzes controversial issues about also provides prospects for future research.

Language: Английский

Citations

0
Insights into convergent evolution of cosexuality in liverworts from the Marchantia quadrata genome DOI Creative Commons
Giacomo Potente, Yukiko Yasui,

Eita Shimokawa

et al.

Cell Reports, Journal Year: 2025, Volume and Issue: 44(4), P. 115503 - 115503

Published: April 1, 2025

Language: Английский

Citations

0
Deleterious mutations can contribute to the evolution of recombination suppression between sex chromosomes DOI Creative Commons
Paul Jay, Amandine Véber, Tatiana Giraud

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 19, 2024

Many organisms have sex chromosomes with large non-recombining regions that expand in a stepwise manner, although the underlying reasons remain poorly understood. Recently, we proposed recombination suppression may evolve simply because of presence recessive deleterious mutations within genomes. Specifically, demonstrated chromosomal inversions suppressing and carrying by chance fewer than average selective advantage. In addition, showed permanent heterozygosity Y-like facilitates fixation these less-loaded sheltering effect, i.e., preventing expression homozygous state when they increase frequency. contrast, similar autosomes suffer from disadvantage as their frequency increases, fixation. However, methodology significance our previous study been questioned. Here, present new analyses further reinforce original claims, demonstrating lower-load advantage effect can explain on over broad range parameter values. We show mechanisms promote at rates exceeding those expected under drift alone. used, control, population size Y chromosome, which, argue, provides appropriate neutral control for effect. also address criticisms regarding focus surviving first 20 generations figure study, stemmed misunderstanding what this was intended to illustrate. Including all inversions, even went extinct generations, does not alter conclusions. Overall, offers support theory based combination addresses questions about its applicability.

Language: Английский

Citations

1
Genetic differentiation in the MAT-proximal region is not sufficient for suppressing recombination in Podospora anserina DOI Open Access
Pierre Grognet, Robert Debuchy, Tatiana Giraud

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 7, 2024

ABSTRACT Recombination is advantageous over the long-term, as it allows efficient selection and purging deleterious mutations. Nevertheless, recombination suppression has repeatedly evolved in sex chromosomes mating-type chromosomes. The evolutionary causes for proximal mechanisms preventing crossing overs are still poorly understood. Several hypotheses have recently been suggested based on theoretical models, particular, that divergence could accumulate neutrally around a sex-determining region reduce rates, self-reinforcing process foster progressive extension of suppression. ascomycete fungus Podospora anserina an excellent model investigating these questions. A 0.8 Mb locus non-recombining, despite being collinear between two mating types. This mostly selfing, so strains highly homozygous, except non-recombining displays differentiation Here, we generated mutant to test hypothesis sequence alone responsible cessation. We replaced mat- idiomorph by mat+ idiomorph, obtain strain sexually compatible with reference isogenic this MAT -proximal region. Crosses showed was suppressed strains, indicating other than inversions or mere fungus. finding suggests selective likely acted suppressing recombination, neutral does not seem hold, at least ARTICLE SUMMARY In many organisms, observed locus. , within 800kb natural genome mating-types, displaying heterozygosity. To determine if heterozygosity can be lack were engineered isogenic, including inhibition persisted, cause Our study provides interesting insight molecular inhibition.

Language: Английский

Citations

0