Biology subjects

Guillon, E.

Publications and source records attributed to Guillon, E..

2 recordsLinked to original sources

bioRxiv2024

Defining a Muscle Stem Cell matrisome signature: from transcriptome data to extracellular matrix niche topology.

Although intensively investigated, the regulation of skeletal muscle stem cells (MuSCs) by their niche remains an open question. The extracellular matrix (ECM) components of the niche represent a dynamic microenvironment that undoubtedly participates in MuSCs behavior. We used bioinformatics analysis of transcriptomic data to define the matrisome profile of skeletal muscle resident cells, comprising genes encoding ECM and ECM-associated proteins. We identified quiescent MuSCs as key ECM producers of the niche, notably through the expression of specific basement membrane genes as Col19a1 and Lama3 and regulators of ECM assembly, Thsd4 and Aebp1. Unexpectedly, quiescent MuSCs also expressed matrisome neurogenesis-related genes. Immunofluorescence staining of selected ECM components showed their organization in isolated murine myofiber bundles. Upon activation, MuSCs strikingly downregulated the niche-related ECM genes and instead expressed genes involved in basement membrane disruption and matrisome genes linked to cell motility. This study identified distinct matrisome signatures of quiescent and activated MuSCs that are consistent with their function in homeostasis and repair of damaged skeletal muscle.

cell biology↗

bioRxiv2023

Dual-topology of collagen XV and tenascin C acts in concert to guide and shape developing motor axons

During development, motor axons are guided towards their muscle target by various extrinsic cues including extracellular matrix (ECM) proteins those identities remain poorly documented. Using single-cell RNA-sequencing of differentiating slow muscle progenitors (SMP) in zebrafish, we charaterized the SMP as a major source of ECM proteins that were computationally predicted to form a basement membrane-like structure tailored for motor axon guidance. Multiple in vivo and in vitro approaches further revealed that motor axon shape and growth relies on the timely expression of the attractive cue Collagen XV-B (ColXV-B) that locally provides motor axons with a permissive soft microenvironment and separately organizes the repulsive cue Tenascin C into a unique functional dual topology. Bioprinted micropatterns mimicking their unique topology provide compelling evidence that it represents a sufficient condition to elicit directional motor axon growth. Our study provides the first evidence that ECM topology and stiffness critically influence motor axon navigation in vertebrates with potential applications in regenerative medicine for peripheral nerve injury.

developmental biology↗