Biology subjects

Rhinn, M.

Publications and source records attributed to Rhinn, M..

4 recordsLinked to original sources

bioRxiv2025

Developmental senescence profiling reveals Eda2r as a common mediator in the core senescence program

Cellular senescence is a distinct state of stable cell-cycle arrest coupled to a dynamic secretory phenotype. Although transient senescence contributes to embryonic development and regeneration, its relationship to the chronic forms associated with damage and aging is unclear. Here, we generated a p21-reporter mouse to isolate and transcriptionally profile senescent cells in Apical Ectodermal Ridge of the developing limb. Comparative analysis of these cells with diverse in vitro and in vivo senescence models revealed a conserved gene program encompassing canonical markers and regulators, with previously unassociated factors. Among these, ectodysplasin A2 receptor (Eda2r) emerged as a critical modulator required for senescence-associated transcriptional and functional features. Our findings define a shared molecular framework linking developmental and pathological senescence and identify conserved effectors such as Eda2r as potential targets for therapeutic modulation of senescent cell function.

cell biology↗

bioRxiv2025

Senescent cells exhibit features of developmental signaling centres

Cellular senescence is a state that contributes to tissue patterning during development and tissue repair, but which becomes misregulated in ageing and disease. The senescence-associated secretory phenotype (SASP) mediates many of the context-dependent effects, yet its molecular composition and evolutionary origins remain incompletely understood. Here, we characterize the SASP signature of developmental senescent cells and find that it is enriched for genes encoding major developmental signaling pathways. Integrative analyses of in vitro and in vivo transcriptomes reveal that human and mouse senescent cells across diverse contexts consistently activate these developmental programs, with key morphogens constituting conserved SASP components. Functionally, we show that the SASP is sufficient to induce the expression of central developmental genes and transcription factors across multiple cell types. These findings show that senescent cells resemble developmental signaling centers and uncover developmental signaling reactivation as an evolutionarily conserved feature of senescence, providing conceptual insight into its physiological functions and its pathological impact during ageing.

cell biology↗

bioRxiv2021

Valproic acid induces p19Arf-mediated cellular senescence to cause neurodevelopmental defects

Timely induction of cellular senescence is important during embryonic development and tissue repair, while aberrant activation contributes to many age-related diseases. However, whether abnormal induction of senescence in the embryo contributes to developmental defects remains unclear. To explore this, we investigated the clinically significant model of Valproic acid- (VPA) induced developmental defects. VPA is a widely prescribed drug to treat epilepsy, bipolar disorder and migraine. If taken during pregnancy however, exposure to the developing embryo can cause birth defects, cognitive impairment and Autism-Spectrum Disorder. How VPA causes these developmental defects remains unknown. We used embryonic mice and human organoids to model key features of drug exposure, including exencephaly, microcephaly and spinal defects. In the malformed tissues, in which neurogenesis is defective, we find pronounced induction of cellular senescence in the neuroepithelial cells. Critically, through genetic and functional studies, we identified p19Arf as the instrumental mediator of senescence and microcephaly, but surprisingly, not exencephaly and spinal defects. Together, these findings uncover how misregulated senescence in neuroepithelial cells can contribute to developmental defects.

developmental biology↗

bioRxiv2020

Local retinoic acid directs emergence of the extraocular muscle functional unit

Coordinated development of muscles, tendons, and their attachment sites ensures emergence of functional musculoskeletal units that are adapted to diverse anatomical demands among different species. How these different tissues are patterned and functionally assembled during embryogenesis is poorly understood. Here, we investigated the morphogenesis of extraocular muscles (EOMs), an evolutionary conserved cranial muscle group that is crucial for the coordinated movement of the eyeballs and for visual acuity. By means of lineage analysis, we redefined the cellular origins of periocular connective tissues interacting with the EOMs, which do not arise exclusively from neural crest mesenchyme as previously thought. Using 3D imaging approaches, we established an integrative blueprint for the EOM functional unit. By doing so, we identified a developmental time window where individual EOMs emerge from a unique muscle anlage and establish insertions in the sclera, which sets these muscles apart from classical muscle-to-bone type of insertions. Further, we demonstrate that the eyeballs are a source of diffusible retinoic acid that allow their targeting by the EOMs in a temporal and dose dependent manner. Using genetically modified mice and inhibitor treatments, we find that endogenous local variations in the concentration of retinoids contribute to the establishment of tendon condensations and attachment sites that precede the initiation of muscle patterning. Collectively, our results highlight how global and site-specific programs are deployed for the assembly of muscle functional units with precise definition of muscle shapes and topographical wiring of their tendon attachments.

developmental biology↗