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

Stem cells' transition from quiescence to proliferation enables tissues to self-repair after injury. The activation of the Erk1/2 signaling pathway in neural and muscle stem cells is necessary for cell proliferation and regeneration of spinal cord and skeletal muscle. This study found that after tail amputation in Xenopus laevis larvae, both Ca2+ and Erk1/2 signaling pathways are activated. Precise temporal and tissue-specific activation of these pathways is essential for regulating spinal cord and muscle regeneration. Erk1/2 activity is necessary for an injury-induced increase in intracellular store-dependent Ca2+ dynamics in skeletal muscle, but in spinal cord, injury increases Ca2+ influx-dependent Ca2+ activity independent of Erk1/2 signaling.

• 1
  Erk1/2 signaling is activated in neural and muscle stem cells of regenerating tissues and is necessary for the regeneration of both spinal cord and muscle.
• 2
  Injury induces an increase in Ca2+ dynamics that persists in regenerating tissues and its interaction with Erk1/2 signaling occurs in a tissue-specific manner.
• 3
  In muscle satellite cells, Erk1/2 signaling is specifically activated in the regenerate and in the stump adjacent to the amputation.