Study identifies ECM1 protein as key regulator of liver regeneration after injury
Researchers have identified extracellular matrix protein 1 (ECM1) as a physiological inhibitor of hepatocyte growth factor (HGF) that must be transiently suppressed to allow liver regeneration after partial hepatectomy. Following 70% liver removal in animal models, active HGF levels rise sharply as ECM1 declines, and blocking this decline delays liver mass recovery. The findings reveal a previously unknown molecular gatekeeper mechanism that could inform therapeutic strategies for liver repair and disease.
A preprint study posted to bioRxiv reports that ECM1, a protein found in the extracellular matrix, acts as a physiological brake on HGF signaling during liver regeneration. In a 70% partial hepatectomy model, active HGF levels increase rapidly in parallel with a sharp drop in ECM1, and artificially preventing ECM1 downregulation delays recovery of liver mass. Mechanistically, ECM1 was found to directly bind the active HGF alpha-subunit via a mechanism dependent on residue R392, suppressing downstream c-MET-ERK-MYC signaling and inhibiting hepatocyte proliferation. Loss of ECM1 permits activation of this proliferative pathway, and overexpression of MYC rescues cells from ECM1-mediated growth inhibition. In human liver tissue, proliferating hepatocytes were found to localize specifically to ECM1-negative regions, supporting the model's clinical relevance. The conclusions are further supported by transcriptomic analyses and computational modeling, positioning ECM1 as a transient extracellular gatekeeper whose regulated suppression is essential for HGF-driven tissue repair.
What's missing
As a preprint, this study has not yet undergone peer review, and its findings should be considered preliminary. The study does not fully characterize the upstream mechanisms responsible for ECM1 downregulation after hepatectomy, nor does it address whether therapeutic manipulation of ECM1 is feasible or safe in clinical settings.
What different sources said
- bioRxivCenter
Transient suppression of the ECM1 gatekeeper is essential for HGF/c-MET-driven liver regeneration
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