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Published on: October 27, 2016
Goldfish spexin: solution structure and novel function as a satiety factor in feeding control
Matthew K H Wong1, Kong Hung Sze, Ting Chen
1School of Biological Sciences, University of Hong Kong, Hong Kong, China.
Summary
Spexin (SPX), a newly identified neuropeptide, functions as a satiety factor in goldfish. This study reveals its structure and its role in modulating feeding behaviors by altering appetite-regulating signals in the brain.
Area of Science:
- Neuroendocrinology
- Comparative Physiology
- Structural Biology
Background:
- Spexin (SPX) is a recently discovered neuropeptide with largely unknown biological functions.
- Comparative studies on SPX in non-mammalian species are scarce, limiting our understanding of its evolutionary conservation and diverse roles.
- Investigating SPX in a fish model, like goldfish, can provide insights into its structure-function relationship and physiological effects.
Purpose of the Study:
- To characterize the structure and function of spexin (SPX) in goldfish, a non-mammalian model.
- To investigate the role of SPX in regulating feeding behavior and associated gene expression in the goldfish brain.
- To elucidate the novel function of SPX as a satiety factor by examining its impact on orexigenic and anorexigenic signaling pathways.
Main Methods:
- Cloning of goldfish SPX and characterization of its structure using NMR spectroscopy.
- Analysis of SPX transcript and protein expression in various goldfish tissues, including the brain.
- In vivo and in vitro studies involving feeding behavior assays and gene expression analysis (mRNA levels) following SPX administration.
Main Results:
- Goldfish SPX shares structural similarities with mammalian counterparts, featuring an alpha-helix and a hydrophobic surface.
- SPX transcripts and protein are widely expressed in goldfish tissues, with notable presence in the brain.
- SPX administration inhibited feeding behavior and altered the expression of key appetite-regulating neuropeptides (NPY, AgRP, apelin, CCK, CART, POMC, MCH, CRH) in the goldfish brain.
Conclusions:
- This study provides the first structural elucidation of spexin (SPX) in a non-mammalian species.
- Goldfish SPX acts as a satiety factor, suppressing feeding behavior and modulating central appetite signals.
- SPX represents a conserved regulator of energy homeostasis, with implications for understanding feeding behavior across vertebrates.
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