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Abstract Many annelids can regenerate missing body parts or reproduce asexually, generating all cell types in adult stages. However, the putative adult stem cell populations involved in these processes, and the diversity of cell types generated by them, are still unknown. To address this, we recover 75,218 single cell transcriptomes of the highly regenerative and asexually-reproducing annelidPristina leidyi. Our results uncover a rich cell type diversity including annelid specific types as well as novel types. Moreover, we characterise transcription factors and gene networks that are expressed specifically in these populations. Finally, we uncover a broadly abundant cluster of putative stem cells with a pluripotent signature. This population expresses well-known stem cell markers such asvasa,piwiandnanoshomologues, but also shows heterogeneous expression of differentiated cell markers and their transcription factors. We find conserved expression of pluripotency regulators, including multiple chromatin remodelling and epigenetic factors, inpiwi+cells. Finally, lineage reconstruction analyses reveal computational differentiation trajectories frompiwi+cells to diverse adult types. Our data reveal the cell type diversity of adult annelids by single cell transcriptomics and suggest that apiwi+ cell population with a pluripotent stem cell signature is associated with adult cell type differentiation.
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This content will become publicly available on March 12, 2026
Comparative Transcriptomic Analysis of Embryonic Stem Cells (ESCs) across Mammalian Species
Summary Pluripotency, the ability of cells to self-renew and differentiate into all the cell types in an animal’s body, is vital for mammalian early development. This study presented a comprehensive comparative transcriptomic analysis of embryonic stem cells across multiple mammalian species, defining their progression through expanded/extended, naïve, formative, and primed pluripotency states. Our findings revealed both conserved and species-specific mechanisms underlying pluripotency regulation. We also emphasized the limitations of existing state-specific markers and their limited cross-species applicability, while identifyingde novopluripotency markers that can inform future research. Despite variability in gene expression dynamics, gene co-expression networks showed remarkable conservation across species. Among pluripotency states, the primed state demonstrated the highest conservation, evidenced by shared markers, preserved gene networks, and stronger selective pressures acting on its genes. These findings provide critical insights into the evolution and regulation of pluripotency, laying a foundation for refining stem cell models to enhance their translational potential in regenerative medicine, agriculture, and conservation biology.
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- Award ID(s):
- 2213824
- PAR ID:
- 10592622
- Publisher / Repository:
- bioRxiv
- Date Published:
- Format(s):
- Medium: X
- Institution:
- bioRxiv
- Sponsoring Org:
- National Science Foundation
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