Dose-dependent role of AMH and AMHR2 signaling in male differentiation and regulation of sex determination in Spotted knifejaw (Oplegnathus punctatus) with X1X1X2X2/X1X2Y chromosome system

Cell Communication and Signaling, Journal Year: 2025, Volume and Issue: 23(1)

Published: Feb. 1, 2025

Sex determination mechanisms vary significantly across different chromosomal systems and evolutionary contexts. Nonetheless, the regulatory framework governing multi-sex chromosome system (X1X1X2X2/X1X2Y) remains enigmatic. Through an examination of sex-related genes (dmrt1, hsd11b2, amh, sox9a, sox9b, foxl2, cyp19a), hormonal influences (E2, 11-KT), histological analyses gonadal development, we demonstrate that critical period for sexual differentiation occurs between 35 to 60 days post-hatching (dph). Our multi-omics analysis identified amhr2 as a candidate sex-determining gene, revealing males possess three distinct transcripts (amhr2ay, amhr2by, amhr2cy), whereas females express only one (amhr2a). In situ hybridization assays demonstrated is predominantly localized primary spermatocyte Sertoli cells male testes. Notably, specific mRNA expression enriched in amhr2cy, whose extracellular domain exhibits highest binding affinity Amh protein, with differences manifesting early 5 dph. The outcomes interference (RNAi) experiments indicate knockdown leads reduction male-related gene sox9b), androgen synthesis (hsd11b2, cyp11a), female-related (wnt4, cyp19a, cyp19b). Conversely, overexpression yielded contrasting results. research supports role pivotal gene. Furthermore, dosage effect amhr2, reflected transcript abundance, levels, efficacy, serves fundamental mechanism driving processes Spotted knifejaw.

Language: Английский

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Single-cell sequencing provides clues about the developmental genetic basis of evolutionary adaptations in syngnathid fishes

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

Published: Feb. 3, 2025

Seahorses, pipefishes, and seadragons are fishes from the family Syngnathidae that have evolved extraordinary traits including male pregnancy, elongated snouts, loss of teeth, dermal bony armor. The developmental genetic cellular changes led to evolution these largely unknown. Recent syngnathid genome assemblies revealed suggestive gene content differences provided opportunity for detailed analyses. We created a single-cell RNA sequencing atlas Gulf pipefish embryos understand basis four traits: derived head shape, toothlessness, armor, pregnancy. completed marker analyses, built networks, examined spatial expression select genes. identified osteochondrogenic mesenchymal cells in elongating face express regulatory genes bmp4, sfrp1a , prdm16 . found no evidence tooth primordia cells, we observed re-deployment osteoblast networks developing Finally, epidermal expressed nutrient processing environmental sensing genes, potentially relevant brooding environment. evolutionary innovations composed recognizable cell types, suggesting features originate within existing networks. Future work addressing across multiple stages species is essential understanding how novelties fish evolved.

Language: Английский

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The origin, evolution, and translocation of sex chromosomes in Silurus catfish mediated by transposons

BMC Biology, Journal Year: 2025, Volume and Issue: 23(1)

Published: Feb. 21, 2025

Sex chromosome (SC) evolution is a longstanding topic of focus in evolutionary biology. Teleosts often exhibit rapid turnover SCs and sex-determining (SD) genes, alongside diverse range SC differentiation mechanisms. On the basis new chromosome-scale assemblies three Silurus species (S. microdorsalis, S. glanis, lanzhouensis) two outgroup (Pterocryptis cochinchinensis Kryptopterus bicirrhis), along with our previous meridionalis asotus, we traced genus (Siluriformes), following fate known SD gene amhr2y. Phylogenetic analysis showed that amhr2y occurred at least before divergence Pterocryptis, Kryptopterus, lost P. K. bicirrhis. Chr24 has become ancestor five due to duplication-and-translocation amhr2 mediated by LTR transposon. Then, proto Y was formed maintained shared 60 kb male-specific region (MSY) transposable elements (TEs) expansion gathering. Due continuous TEs accumulation, genes other than MSYs have degenerated or been lost, while non-recombinant regions continue expend, forming different sizes (from 320 550 kb). Two events, one homologous left arm right Chr24) nonhomologous Chr5), occurring among were possibly hAT Helitron transposons. Our results on dynamic trajectory amhr2y, MSYs, catfish indicated variability diversity fish confirmed frequent an important way maintain homology low SCs.

Language: Английский

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The Cause–Effect Model of Master Sex Determination Gene Acquisition and the Evolution of Sex Chromosomes

International Journal of Molecular Sciences, Journal Year: 2025, Volume and Issue: 26(7), P. 3282 - 3282

Published: April 1, 2025

The canonical model of vertebrate sex chromosome evolution predicts a one-way trend toward degradation. However, most chromosomes in lower vertebrates are homomorphic. Recent progress studies determination has resulted the discovery more than 30 master (MSD) genes, which from teleost fish. An analysis MSD gene acquisition, recombination suppression, and chromosome-specific sequences revealed correlations modes acquisition chromosomes. Sex remain homomorphic with genes acquired by simple mutations, duplications, allelic variations, or neofunctionalization; contrast, they become heteromorphic chromosomal inversion, fusion, fission. There is no suppression carrying gained through mutations. In there extensive inversion. limited transposition translocation. We propose cause-effect that as consequence explains various vertebrates. A key factor determining whether non-homologous regions created during genes. Chromosome inversion creates inversely homologous but directly sequences, lead to retain potential. Over time, recurrent inverted leads formation strata may cause degradation Depending on nature deletions regions, evolve dosage compensation, selective retention haplo-insufficient be used an alternative strategy.

Language: Английский

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Characterization of the male-specific region containing the candidate sex-determining gene in Amur catfish (Silurus asotus) using third-generation- and pool-sequencing data

International Journal of Biological Macromolecules, Journal Year: 2023, Volume and Issue: 248, P. 125908 - 125908

Published: July 22, 2023

Language: Английский

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Sex chromosome cycle as a mechanism of stable sex determination

The Journal of Biochemistry, Journal Year: 2024, Volume and Issue: 176(2), P. 81 - 95

Published: July 10, 2024

Abstract Recent advances in DNA sequencing technology have enabled the precise decoding of genomes non-model organisms, providing a basis for unraveling patterns and mechanisms sex chromosome evolution. Studies different species yielded conflicting results regarding traditional theory that chromosomes evolve from autosomes via accumulation deleterious mutations degeneration Y (or W) chromosome. The concept ‘sex cycle,’ emerging this context, posits at any stage cycle (i.e., differentiation, degeneration, or loss), turnover can occur while maintaining stable determination. Thus, understanding drive both persistence each is crucial. In review, we integrate recent findings on underlying maintenance turnover, with special focus several organisms having unique chromosomes. Our review suggests diversity determination underappreciated emphasizes need more research cycle.

Language: Английский

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Molecular parallelism in the evolution of a master sex‐determining role for the anti‐Mullerian hormone receptor 2 gene (amhr2) in Midas cichlids

Molecular Ecology, Journal Year: 2022, Volume and Issue: 32(6), P. 1398 - 1410

Published: April 11, 2022

The evolution of sex chromosomes and their differentiation from autosomes is a major event during genome that happened many times in several lineages. repeated lability sex-determination mechanisms fishes makes this well-suited system to test for general patterns evolution. According current theory, triggered by the suppression recombination following new master sex-determining gene. However, molecular establish are known few examples, owing intrinsic difficulties assembling regions (SDRs). development forward-genetics long-read sequencing have generated wealth data questioning central aspects theory. Here, we demonstrate Midas cichlids determined an XY system, identify assemble SDR combining forward-genetics, optical mapping. We show how long-reads aid detection artefacts genotype-phenotype mapping arise incomplete assemblies. male-specific region restricted 100-kb segment on chromosome 4 harbours transposable elements Y-specific duplicate anti-Mullerian receptor 2 gene, which has evolved functions repeatedly. Our suggest amhr2Y originated interchromosomal translocation 20 pre-dating split Flier cichlids. In latter, it pseudogenized translocated another chromosome. Duplication genes common route establishing determiners, highlighting role parallelism determination.

Language: Английский

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The genetic basis of the leafy seadragon’s unique camouflage morphology and avenues for its efficient conservation derived from habitat modeling

Science China Life Sciences, Journal Year: 2023, Volume and Issue: 66(6), P. 1213 - 1230

Published: May 12, 2023

Language: Английский

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Leafy and weedy seadragon genomes connect genic and repetitive DNA features to the extravagant biology of syngnathid fishes

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(26)

Published: June 22, 2022

Seadragons are a remarkable lineage of teleost fishes in the family Syngnathidae, renowned for having evolved male pregnancy. Comprising three known species, seadragons widely recognized and admired their fantastical body forms coloration, specific habitat requirements have made them flagship representatives marine conservation natural history interests. Until recently, gap has been lack significant genomic resources seadragons. We produced gene-annotated, chromosome-scale genome models leafy weedy seadragon to advance investigations evolutionary innovation elaboration morphological traits as well pipefish seahorse relatives. identified several interesting features genomes, including divergent noncoding regions near developmental gene important integumentary outgrowth, high genome-wide density repetitive DNA, recent expansions transposable elements vesicular trafficking family. Surprisingly, comparative analyses leveraging genomes additional syngnathid outgroup revealed striking, syngnathid-specific losses fibroblast growth factors (FGFs), which likely involve reorganization highly conserved regulatory networks ways that not previously documented populations. The presented here serve tools future studies processes syngnathids hold value extravagant

Language: Английский

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Independent Evolution of Sex Chromosomes and Male Pregnancy–Related Genes in Two Seahorse Species

Molecular Biology and Evolution, Journal Year: 2022, Volume and Issue: 40(1)

Published: Dec. 29, 2022

Unlike birds and mammals, many teleosts have homomorphic sex chromosomes, changes in the chromosome carrying sex-determining locus, termed "turnovers", are common. Recent turnovers allow studies of several interesting questions. One question is whether new regions evolve to become completely non-recombining, if so, how why. Another (as predicted) evolutionary that benefit one accumulate newly sex-linked region. To study these questions, we analyzed genome sequences two seahorse species Syngnathidae, a fish group which evolved unique structure, male brood pouch. We find both XY systems, but their pairs not homologs, implying at least turnover event has occurred. The Y-linked occupy 63.9% 95.1% entire do exhibit extensive sequence divergence with X-linked homologs. evidence for occasional recombination between extant chromosomes may account homomorphism. argue did by suppression after turnover, ancestral nature low crossover rates regions. With such an landscape, can instantly create Finally, test adaptive evolution pouch-related genes they became seahorse.

Language: Английский

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