Rediscovering a Forgotten Link: TSPO and RIM-BP1 in Appetite Regulation

Nutr Rev. 2025 May 1;83(5):961-964. doi: 10.1093/nutrit/nuae127.

Abstract

The translocator protein of 18 kDa (TSPO) and RIM binding protein 1 (RIM-BP1) are both heavily expressed in neurons at the olfactory bulb. These proteins have overlapping functional profiles and are both implicated in the development of obesity. Over 20 years ago, a yeast 2-hybrid experiment discovered that RIM-BP1 interacts with a peptide constructed from a fraction of the TSPO sequence. Considering these data, the authors predict that the interaction between RIM-BP1 and TSPO could alter the olfactory system's mediation of appetite. Despite the therapeutic potential of this interaction, it has never been confirmed if the full TSPO protein and RIM-BP1 interact. The interaction is instead often cited as physiologically irrelevant. This commentary revisits the forgotten interaction between TSPO and RIM-BP1, reviewing all relevant literature discussing their relationship. Contrary to common discourse that the RIM-BP1 and TSPO are potential binding partners, while the interaction may regulate many neurological functions, existing evidence suggests that the interaction would have a specific role in odor-guided appetite. Further research into the nutritional neuroscientific consequences of TSPO/RIM-BP1 interactions should therefore be conducted.

Keywords: TSPO; appetite regulation; odor-guided eating; olfaction; olfactory bulb.

Publication types

  • Review

MeSH terms

  • Animals
  • Appetite / physiology
  • Appetite Regulation* / physiology
  • Carrier Proteins* / metabolism
  • Carrier Proteins* / physiology
  • Humans
  • Nerve Tissue Proteins* / metabolism
  • Obesity / metabolism
  • Olfactory Bulb / metabolism
  • Olfactory Bulb / physiology
  • Receptors, GABA* / metabolism
  • Receptors, GABA* / physiology

Substances

  • Receptors, GABA
  • TSPO protein, human
  • Carrier Proteins
  • Nerve Tissue Proteins