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Korean Society for Biochemistry and Molecular Biology (생화학분자생물학회)
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Epac: new emerging cAMP-binding protein

  • Lee, Kyungmin (Laboratory for Behavioral Neural Circuitry and Physiology, Department of Anatomy, Brain Science & Engineering Institute, School of Medicine, Kyungpook National University)
  • Received : 2020.10.15
  • Accepted : 2020.11.30
  • Published : 2021.03.31
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Abstract

The well-known second messenger cyclic adenosine monophosphate (cAMP) regulates the morphology and physiology of neurons and thus higher cognitive brain functions. The discovery of exchange protein activated by cAMP (Epac) as a guanine nucleotide exchange factor for Rap GTPases has shed light on protein kinase A (PKA)-independent functions of cAMP signaling in neural tissues. Studies of cAMP-Epac-mediated signaling in neurons under normal and disease conditions also revealed its diverse contributions to neurodevelopment, synaptic remodeling, and neurotransmitter release, as well as learning, memory, and emotion. In this mini-review, the various roles of Epac isoforms, including Epac1 and Epac2, highly expressed in neural tissues are summarized, and controversies or issues are highlighted that need to be resolved to uncover the critical functions of Epac in neural tissues and the potential for a new therapeutic target of mental disorders.

Keywords

References

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