Related Experiment Video
Updated: Jun 9, 2026
08:09
Vasodilation of Isolated Vessels and the Isolation of the Extracellular Matrix of Tight-skin Mice
Published on: March 24, 2017
Understanding insulin-like peptide 5 (INSL5) and relaxin family peptide receptor 4 (RXFP4): structure, signalling,
Hongkang Wu1, Huahao Wang1, Isabelle Riches1
1Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, The University of Melbourne Parkville Victoria 3052 Australia akhter.hossain@unimelb.edu.au.
RSC Chemical Biology
|June 8, 2026
Summary
Insulin-like peptide 5 (INSL5) regulates gut function by activating its receptor RXFP4. This signaling pathway is crucial for colonic motility and offers potential therapeutic targets for chronic constipation.
Area of Science:
- Gastroenterology
- Endocrinology
- Molecular Biology
Background:
- Insulin-like peptide 5 (INSL5) is produced by gut L cells and belongs to the relaxin/insulin peptide family.
- Its receptor, relaxin family peptide receptor 4 (RXFP4), is mainly expressed in the gastrointestinal tract and signals via Gi proteins.
- Emerging evidence highlights the INSL5-RXFP4 axis as a key regulator of gastrointestinal physiology, particularly colonic motility.
Purpose of the Study:
- To review the current understanding of INSL5 and RXFP4 structure-function relationships.
- To summarize advances in INSL5 analogue design and receptor activation signaling.
- To discuss the physiological and pharmacological roles of INSL5-RXFP4 signaling in colonic motility and its therapeutic potential.
Main Methods:
- Literature review of existing studies on INSL5 and RXFP4.
- Analysis of structure-function relationships and signaling mechanisms.
- Evaluation of physiological and pharmacological evidence for INSL5-RXFP4 in colonic motility.
Main Results:
- The INSL5-RXFP4 signaling axis plays a significant role in regulating colonic motility.
- Understanding structure-function relationships and signaling pathways is advancing.
- INSL5 analogues are being developed, offering new research tools and therapeutic leads.
Conclusions:
- The INSL5-RXFP4 system is a critical regulator of colonic function.
- This axis presents promising opportunities for developing treatments for chronic constipation.
- Further research into chemical probes and therapeutic leads targeting this system is warranted.
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