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bioRxiv · 10.1101/2021.09.12.459948

Injury-induced Erk1/2 signaling enhances Ca2+ activity and is necessary for regeneration of spinal cord and skeletal muscle

Levin, J. B.·Borodinsky, L. N.
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Abstract

The transition of stem cells from quiescence to proliferation enables tissues to self-repair. The signaling mechanisms driving these stem-cell-status decisions are still unclear. Ca2+ and the extracellular signal-regulated kinase (Erk1/2) are two signaling pathways that have the potential to coordinate multiple signals to promote a specific cellular response. They both play important roles during development but their roles during regeneration are not fully deciphered. Here we show in Xenopus laevis larvae that both Ca2+ and Erk1/2 signaling pathways are activated after tail amputation. In response to injury, we find that Erk1/2 signaling is activated in neural and muscle stem cells and is necessary for spinal cord and skeletal muscle regeneration. Finally, we show in vivo that Erk1/2 action is necessary for an injury-induced increase in intracellular store-dependent Ca2+ dynamics in skeletal muscle-associated tissues but that in spinal cord, injury increases Ca2+ influx-dependent Ca2+ activity independent of Erk1/2 signaling. This study suggests that precise temporal and tissue-specific activation of Ca2+ and Erk1/2 pathways is essential for regulating tissue regeneration.

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Levin, J. B., Borodinsky, L. N.. 2021-09-15. Injury-induced Erk1/2 signaling enhances Ca2+ activity and is necessary for regeneration of spinal cord and skeletal muscle. https://doi.org/10.1101/2021.09.12.459948

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