A comparative analysis of planarian genomes reveals regulatory conservation in the face of rapid structural divergence

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Сен. 18, 2024

Язык: Английский

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An ear for an ear, but only if you are a deomyinid

Proceedings of the National Academy of Sciences, Год журнала: 2025, Номер 122(6)

Опубликована: Фев. 5, 2025

Язык: Английский

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Silencing of β-catenin1 blocks tail regeneration, but does not induce head regeneration in the flatworm Macrostomum lignano

Опубликована: Март 18, 2025

Abstract β-Catenin has two major functions conserved across metazoans. It enables the interaction of classical cadherin with actin and it is main transcription factor activated by canonical Wnt pathway. In these functions, acts in patterning body axis early embroys, cell differentiation proliferation. flatworms, four β-catenin homologs have been identified planarian Schmidtea mediterranea. Functional studies revealed that only Smed-β-catenin1 can transduce signal plays a part defining posterior identity. We made phylogenetic reconstruction retrieved from wide range flatworms analysed role during regeneration Macrostomum lignano . at least copies all taxa except Catenulida; this suggests duplication occurred ancestrally Rhabditophora. M. , we detected 3 homologs. Upon knockdown homologs, Mlig-β-catenin1 blocked blastema formation tail. After knockdown, regenerates restored normal tails but instances imperfect or duplicated tails. Different to planarians, Mlig-β-catenins individually combination failed rescue head amputation levels anterior regenerates. Together, findings suggest β-catenin1 responsible for identity specification also Our study demonstrates ability upon may be an apomorphy not ancestral character flatworms.

Язык: Английский

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A comparative analysis of planarian genomes reveals regulatory conservation in the face of rapid structural divergence

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2023, Номер unknown

Опубликована: Дек. 23, 2023

Abstract The planarian Schmidtea mediterranea can regenerate its entire body from small tissue fragments and is studied as regeneration model species. assembly functional analysis of genomes has proven challenging due high A/T content (70% A/T), repetitive nature, limited transferability routine laboratory protocols to their divergent biochemistry. Only few often fragmented genome assemblies are currently available, open challenges include the provision well-annotated chromosome-scale reference species other planarians for a comparative evolution perspective. Here we report haplotype-phased, high-quality gene annotations sexual S2 strain S. provide putative regulatory region via optimized ATAC-seq ChIP-seq protocols. To additionally leverage sequence conservation element annotations, generated chromatin accessibility data three closest relatives : polychroa , nova lugubris . We find substantial divergence in protein-coding sequences regions, yet reveal remarkable ChIP-mark bearing regions identified promoters enhancers resulting high-confidence set evolutionary conserved provides valuable resource circuits within taxon. In addition, our four first perspective on evolution. Our analyses frequent retrotransposon-associated chromosomal inversions inter-chromosomal translocations that lead degradation synteny across genus. Interestingly, further independent near-complete losses ancestral metazoan two flatworm groups, indicating platyhelminth largely evolve without syntenic constraints. work resources research community sets foundation genomics planarians. contrast between fast structural elements, suggesting unique flatworms where positioning may not be essential.

Язык: Английский

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Cell proliferation and cell death during whole‐body regeneration in the demosponge Halisarca dujardinii

FEBS Letters, Год журнала: 2025, Номер unknown

Опубликована: Фев. 27, 2025

Sponges (phylum Porifera) are early‐branching metazoans demonstrating an outstanding example of whole‐body regeneration, cell reaggregation. During the process, single cells form aggregates capable progressive development and reconstruction intact sponges. This study provides first comprehensive analysis proliferation death during reaggregation in a marine demosponge, Halisarca dujardinii . Relatively high proliferative activity occurs at early late stages seems to be consequence tissue turnover rather than prerequisite for aggregate development. The contribution is limited short period epithelization. Cell demosponges appears morphallactic restorative process relying primarily on migration, dedifferentiation, transdifferentiation.

Язык: Английский

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A comparative analysis of planarian regeneration specificity reveals tissue polarity contributions of the axial cWnt signalling gradient

Опубликована: Март 13, 2025

Planarians exhibit remarkable whole-body regeneration abilities. The formation of heads at forward-facing wounds and tails rearward-facing suggests an intrinsic tissue polarity guiding regeneration. While the underlying mechanisms remain unclear, reports double-headed regenerates from increasingly narrow fragments have long been hypothesised to reflect gradient-based specification. Here, we systematically re-examine this hypothesis in modern model species Schmidtea mediterranea a representative genus likely used original studies, Girardia sinensis . never observed double-heads S. , G. readily regenerated manner dependent on piece length, anatomical position body size. We found that reduced robustness was partially explained by wound site-symmetric expression head determinant notum which is highly anterior-specific Exploring what else might mediate head/tail specificity examined role conserved tail-to-head cWnt signalling gradient. By developing time-resolved pharmacological approach reduce gradient slope without affecting wound-induced dynamics, increased incidence regenerates. In addition, size-dependence double-head correlated with decreasing steepness due scaling. Taken together, our results indicate may contribute planarian specificity. Furthermore, they suggest composed multiple parallely-acting cues, differential reliance contributes interspecies variation

Язык: Английский

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A comparative analysis of planarian regeneration specificity reveals tissue polarity contributions of the axial cWnt signalling gradient

Опубликована: Март 13, 2025

Planarians exhibit remarkable whole-body regeneration abilities. The formation of heads at forward-facing wounds and tails rearward-facing suggests an intrinsic tissue polarity guiding regeneration. While the underlying mechanisms remain unclear, reports double-headed regenerates from increasingly narrow fragments have long been hypothesised to reflect gradient-based specification. Here, we systematically re-examine this hypothesis in modern model species Schmidtea mediterranea a representative genus likely used original studies, Girardia sinensis . never observed double-heads S. , G. readily regenerated manner dependent on piece length, anatomical position body size. We found that reduced robustness was partially explained by wound site-symmetric expression head determinant notum which is highly anterior-specific Exploring what else might mediate head/tail specificity examined role conserved tail-to-head cWnt signalling gradient. By developing time-resolved pharmacological approach reduce gradient slope without affecting wound-induced dynamics, increased incidence regenerates. In addition, size-dependence double-head correlated with decreasing steepness due scaling. Taken together, our results indicate may contribute planarian specificity. Furthermore, they suggest composed multiple parallely-acting cues, differential reliance contributes interspecies variation

Язык: Английский

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Developmental onset of planarian whole-body regeneration depends on axis reset

Current Biology, Год журнала: 2025, Номер unknown

Опубликована: Апрель 1, 2025

Язык: Английский

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Unsolved morphogenesis problems and the hidden order

Biosystems, Год журнала: 2024, Номер 239, С. 105218 - 105218

Опубликована: Апрель 21, 2024

Язык: Английский

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Enduring questions in regenerative biology and the search for answers

Communications Biology, Год журнала: 2023, Номер 6(1)

Опубликована: Ноя. 9, 2023

Abstract The potential for basic research to uncover the inner workings of regenerative processes and produce meaningful medical therapies has inspired scientists, clinicians, patients hundreds years. Decades studies using a handful highly model organisms have significantly advanced our knowledge key cell types molecular pathways involved in regeneration. However, many questions remain about how unfold regeneration-competent species, they are curtailed non-regenerative organisms, might be induced (or restored) humans. Recent technological advances genomics, biology, computer science, bioengineering, stem hold promise collectively provide new experimental evidence different accomplish process In theory, this should inform design clinical approaches medicine. A deeper understanding tissues organs regenerate will also undoubtedly impact adjacent scientific fields. To best apply adapt these technologies ways that break long-standing barriers answer critical regeneration, we must combine deep developmental evolutionary biologists with hard-earned expertise scientists mechanistic technical end, perspective is based on conversations from workshop organized at Banbury Center, during which diverse cross-section regeneration community experts various discussed enduring biology. Here, share group identified as significant unanswered, i.e., known unknowns. We describe obstacles limiting progress answering expanding number diversity used essential deepening capacity. Finally, propose investigating problems collaboratively across network researchers advance field unexpected insights into important related areas biology

Язык: Английский

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