Pharmacological modulation of dual melanocortin-4 receptor signaling by melanocortin receptor accessory proteins in the Xenopus laevis

J Cell Physiol. 2021 Aug;236(8):5980-5993. doi: 10.1002/jcp.30280. Epub 2021 Jan 26.

Abstract

Physiological modulation of melanocortin-4 receptor (MC4R) signaling by MRAP2 proteins plays an indispensable role in appetite control and energy homeostasis in the central nervous system. Great interspecies differences of the interaction and regulation of melanocortin receptors by MRAP protein family have been reported in several diploid vertebrates but never been investigated in the tetrapod amphibian Xenopus laevis. Here, we performed phylogenetic and synteny-based analyses to explore the evolutionary aspects of dual copies of X. laevis MC4R (xlMC4R) and MRAP2 (xlMRAP2) proteins. Our data showed that xlMRAPs directly interacted with xlMC4Rs on the cell surface as a functional antiparallel dimeric topology and pharmacological studies suggested a homology specific regulatory pattern of the melanocortin system in X. laevis.

Keywords: MC4R; MRAP; MRAP2; Xenopus laevis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism
  • Animals
  • Appetite Regulation / physiology
  • Carrier Proteins / metabolism
  • Cell Membrane / metabolism
  • Homeostasis / physiology
  • Melanocortins / metabolism*
  • Receptor, Melanocortin, Type 4 / genetics
  • Receptor, Melanocortin, Type 4 / metabolism*
  • Receptors, Melanocortin / metabolism*
  • Signal Transduction / physiology
  • Xenopus laevis / metabolism*

Substances

  • Adaptor Proteins, Signal Transducing
  • Carrier Proteins
  • Melanocortins
  • Receptor, Melanocortin, Type 4
  • Receptors, Melanocortin