Hypocretin is an early member of the incretin gene family

doi:10.1016/S0304-3940(02)00195-7

Neuroscience Letters

Volume 324, Issue 3, 24 May 2002, Pages 169-172

https://doi.org/10.1016/S0304-3940(02)00195-7 Get rights and content

Abstract

Recent studies have revealed that the hypothalamic hypocretin (Hcrt) neuropeptide system is centrally involved in mammalian REM sleep and that it may have other diverse physiological roles. The aims of this work were to learn when HCRT emerged and to test our previous hypothesis that it was created by a circular permutation of an incretin superfamily gene. We found HCRT in fish and believe the gene arose approximately 650 million years ago, in the early chordate lineage. Our comparison of Hcrts to the most similar members of the incretin peptide superfamily leads us to conclude that HCRTs are indeed incretin paralogs that arose by a genetic circular permutation.

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Acknowledgements

We thank Beth Thomas for critical review and Luis de Lecea for stimulating discussions. This work was funded by NIH Grant GM32355 to J.G.S. and a supplemental fellowship of the same to C.E.A.

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Hypocretin is an early member of the incretin gene family

Abstract

Section snippets

Acknowledgements

FEBS Lett.

Prog. Biophys. Mol. Biol.

Cell

Lancet

Peptides

The hypocretins: hypothalamus-specific peptides with neuroexcitatory activity

Proc. Natl. Acad. Sci. USA