Improved synapsis dynamics accompany meiotic stability in Arabidopsis arenosa autotetraploids

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

Published: Jan. 8, 2025

Abstract During meiosis, the correct pairing, synapsis, and recombination of homologous chromosome pairs is critical for fertility sexual eukaryotes. These processes are challenged in polyploids, which possess additional copies each chromosome. Polyploidy thus provides a unique context to study how evolution can modify meiotic programs response challenges. We previously observed that Arabidopsis arenosa newly formed (neo-)polyploids, synapsis defects precede chromosomes associating aberrant multivalent univalent configurations. Here we dynamics genotypes with varying levels stability ask whether efficient synaptic progression key component evolving stable tetraploid meiosis. develop method quantify using foci pro-crossover factor HEI10 as reference. initially appears at many small loci before accumulating only crossover sites. In diploids, this transition begins while there still significant asynapsis, quickly declines accumulation fewer progresses. neo-tetraploids, suboptimal elongation initiation sites, perhaps defective precedes stalling onset accumulation. established tetraploids, when asynapsis minimal, suggesting an enhanced HEI10/synapsis co-dynamic (even compared diploids). Hybrids generated by crossing neo- tetraploids exhibit intermediate phenotypes. find extent correlates positively numbers, well higher frequency multivalents univalent, disturb segregation. Our work supports hypothesis improving efficiency important polyploid stability. Significance Statement pair subsequently form synaptonemal complex, maturation DNA events. How formation coordinated where multiple sets complicate pair-wise interactions, remains unclear. Leveraging ‘developmental clock,’ quantified new . Synapsis severely compromised ones it more even than diploids. Notably, correlated excess crossovers, compromises connecting connect homologs multivalents. findings highlight polyploids.

Language: Английский

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The conserved ATPase PCH-2 controls the number and distribution of crossovers by antagonizing their formation in C. elegans

Published: Feb. 7, 2025

Meiotic crossover recombination is essential for both accurate chromosome segregation and the generation of new haplotypes natural selection to act upon. This requirement known as assurance one example control. While conserved role ATPase, PCH-2, during meiotic prophase has been enigmatic, a universal phenotype when pch-2 or its orthologs are mutated change in number distribution crossovers. Here, we show that PCH-2 controls crossovers by antagonizing their formation. antagonism produces different effects at stages prophase: early prophase, prevents double strand breaks from becoming crossover-eligible intermediates, limiting formation sites initial break homolog interactions. Later winnows contributing designation ultimately, assurance. We also demonstrate accomplishes this regulation through HORMAD, HIM-3. Our data strongly support model which PCH-2’s remodel HORMADs throughout destabilize precursors, coordinate with synapsis, contribute progressive implementation recombination, guaranteeing

Language: Английский

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Full-length transcriptome assembly and RNA-Seq integration of diploid and tetraploid ryegrass to investigate differences in cd uptake and accumulation among ryegrass with different ploidy levels

BMC Genomics, Journal Year: 2025, Volume and Issue: 26(1)

Published: Feb. 10, 2025

The accumulation of cadmium (Cd) in ryegrass (Lolium multiflorum Lamk.) as a widely used pasture plant poses serious risk to food safety. This study aimed investigate the differences phenotypes, physiology, and expression metal transporters between four genotypes (diploid/tetraploid Cd-tolerant/sensitive). diploid/Cd-sensitive were found uptake, accumulate, translocate more Cd compared tetraploid/Cd-tolerant genotypes. with soluble components facilitated transfer from root shoot sensitive Tetraploid Cd-tolerant Chuansi No.1 accumulated less shoots but higher ratio cell wall, making it promising model for studying mechanisms resistance stress. complex regulatory system dilution effect contributed lower uptake tetraploid Moreover, exhibited genes that promoted efflux, which could contribute their accumulation. Overall, this sheds light on physiological transcriptional by different polyploids, providing guidance breeding soil improvement.

Language: Английский

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The synaptonemal complex stabilizes meiosis in allotetraploid Brassica napus and autotetraploid Arabidopsis thaliana

New Phytologist, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 18, 2025

Summary Polyploidy plays a key role in genome evolution and crop improvement. The formation of bivalents rather than multivalents during meiosis polyploids is essential to ensure meiotic stability optimal fertility the species. However, mechanisms preventing multivalent recombination remain obscure. We studied synaptonemal complex polyploid by mutating transverse filament component ZYP1 allotetraploid Brassica napus autotetraploid Arabidopsis. In B. , mutation all four copies results pairing accompanied partner switches, nonhomologous recombination, interlocks, leading severe chromosome entanglement abortion. presence only one functional allele compromises synapsis associations occur at nonsynaptic regions. Moreover, disruption causes complete shift from predominantly exclusively pachytene cells synthetic Arabidopsis thaliana resulting dramatic increase frequency metaphase I. conclude that ZYP1‐mediated assembly facilitates pairwise homologous both allopolyploid autopolyploid species ensuring diploid‐like bivalent meiosis.

Language: Английский

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The conserved ATPase PCH-2 controls the number and distribution of crossovers by antagonizing their formation in Caenorhabditis elegans

eLife, Journal Year: 2025, Volume and Issue: 13

Published: Feb. 18, 2025

Meiotic crossover recombination is essential for both accurate chromosome segregation and the generation of new haplotypes natural selection to act upon. This requirement known as assurance one example control. While conserved role ATPase, PCH-2, during meiotic prophase has been enigmatic, a universal phenotype when pch-2 or its orthologs are mutated change in number distribution crossovers. Here, we show that PCH-2 controls crossovers by antagonizing their formation. antagonism produces different effects at stages prophase: early prophase, prevents double-strand breaks from becoming crossover-eligible intermediates, limiting formation sites initial break homolog interactions. Later winnows contributing designation ultimately, assurance. We also demonstrate accomplishes this regulation through HORMAD, HIM-3. Our data strongly support model which PCH-2’s remodel HORMADs throughout destabilize precursors coordinate with synapsis, ensuring progressive implementation explaining function pachytene checkpoint

Language: Английский

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Somatic variations in the meiosis‐specific gene CrMER3 confer seedlessness in a citrus bud sport

Journal of Integrative Plant Biology, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 21, 2025

Seedlessness is a most valuable trait in fruit crops for fresh consumption and processing. The mutations essential meiosis genes are known to confer sterility seed abortion plants. However, defects have rarely been reported crops. Here, we found caused seedless citrus bud sport cultivar, with massive unpaired univalents during diakinesis, indicating disruption crossover formation. A non-functional CrMER3A-103 bp allele 103-bp deletion the gene body, together other CrMER3a T exon, were identified cultivar. CrMER3 protein was undetectable at meiotic prophase I knock out of resulted precocious Mini-citrus. Therefore, natural variation responsible seedlessness this originated from primitive wild mandarin passed cultivated mandarins. Kompetitive Allele-Specific PCR (KASP) marker developed identify germplasm screen potential sterile hybrids cross breeding. Uncovering enhances our understanding mechanisms controlling facilitates breeding varieties.

Language: Английский

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Improved synapsis dynamics accompany meiotic stability in Arabidopsis arenosa autotetraploids

Proceedings of the National Academy of Sciences, Journal Year: 2025, Volume and Issue: 122(19)

Published: May 7, 2025

During meiosis, the correct pairing, synapsis, and recombination of homologous chromosome pairs is critical for fertility sexual eukaryotes. These processes are challenged in polyploids, which possess additional copies each chromosome. Polyploidy thus provides a unique context to study how evolution can modify meiotic programs response challenges. We previously observed that newly formed (neo-)polyploids Arabidopsis arenosa , synapsis defects precede chromosomes associating aberrant multivalent univalent configurations. Here, we dynamics genotypes with varying levels stability ask whether efficient synaptic progression key component evolving stable tetraploid meiosis. develop method quantify using foci pro-crossover factor HEI10 as reference. initially appears at many small before accumulating only crossover sites. In diploids, this transition begins while significant asynapsis still present, though it quickly declines accumulates fewer foci. neo-tetraploids, suboptimal elongation initiation sites stalled perhaps due defective occurs onset accumulation. established tetraploids, accumulation when near complete, suggesting enhanced HEI10/synapsis codynamics (even compared diploids). Hybrids generated by crossing neo- tetraploids exhibit intermediate phenotypes. find extent correlates positively numbers, frequency multivalents univalents, disturb segregation. Our work supports hypothesis improving efficiency important polyploid stability.

Language: Английский

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Transcription factors BnaC09.FUL and BnaC06.WIP2 antagonistically regulate flowering time under long-day conditions in Brassica napus

Journal of genetics and genomics/Journal of Genetics and Genomics, Journal Year: 2024, Volume and Issue: 52(5), P. 650 - 665

Published: Dec. 12, 2024

Language: Английский

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The conserved ATPase PCH-2 controls the number and distribution of crossovers by antagonizing crossover formation inC. elegans

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

Published: Aug. 13, 2024

Abstract Meiotic crossover recombination is essential for both accurate chromosome segregation and the generation of new haplotypes natural selection to act upon. While conserved role ATPase, PCH-2, during meiotic prophase has been enigmatic, a universal phenotype that observed when pch-2 or its orthologs are mutated change in number distribution crossovers. Here, we show PCH-2 controls crossovers by antagonizing formation. This antagonism produces different effects at stages prophase: early prophase, prevents double strand breaks from becoming crossovers, limiting sites initial DSB formation homolog interactions. Later winnows crossover-eligible intermediates, contributing reinforcement designation ultimately, assurance. We also demonstrate accomplishes this regulation through HORMAD, HIM-3. Our data strongly support model which PCH-2’s remodel HORMADs throughout destabilize precursors, coordinate with synapsis, contribute progressive implementation recombination, guaranteeing control.

Language: Английский

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The conserved ATPase PCH-2 controls the number and distribution of crossovers by antagonizing crossover formation in C. elegans

Published: Oct. 30, 2024

Meiotic crossover recombination is essential for both accurate chromosome segregation and the generation of new haplotypes natural selection to act upon. While conserved role ATPase, PCH-2, during meiotic prophase has been enigmatic, a universal phenotype that observed when pch-2 or its orthologs are mutated change in number distribution crossovers. Here, we show PCH-2 controls crossovers by antagonizing formation. This antagonism produces different effects at stages prophase: early prophase, prevents double strand breaks from becoming crossovers, limiting sites initial DSB formation homolog interactions. Later winnows crossover-eligible intermediates, contributing reinforcement designation ultimately, assurance. We also demonstrate accomplishes this regulation through HORMAD, HIM-3. Our data strongly support model which PCH-2’s remodel HORMADs throughout destabilize precursors, coordinate with synapsis, contribute progressive implementation recombination, guaranteeing control.

Language: Английский

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