PT  - JOURNAL ARTICLE
AU  - Raul Valente
AU  - Luís Q. Alves
AU  - Matilde Nabais
AU  - Filipe Alves
AU  - Isabel Sousa-Pinto
AU  - Raquel Ruivo
AU  - L. Filipe C. Castro
TI  - Differential Cetacea Circadian Rhythmicity is associated with the molecular erosion of Cortistatin
AID  - 10.1101/2020.05.11.087833
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.05.11.087833
4099  - http://biorxiv.org/content/early/2020/05/12/2020.05.11.087833.short
4100  - http://biorxiv.org/content/early/2020/05/12/2020.05.11.087833.full
AB  - The ancestors of Cetacea underwent profound morpho-physiological alterations. By displaying an exclusive aquatic existence, cetaceans evolved unique patterns of locomotor activity, vigilant behaviour, thermoregulation and circadian rhythmicity. Deciphering the molecular landscape governing many of these adaptations is key to understand the evolution of phenotypes. Here, we investigate Cortistatin (CORT), a neuropeptide displaying an important role mammalian biorhythm regulation. This neuropeptide is a known neuroendocrine factor, stimulating slow-wave sleep, but also involved in the regulation of energy metabolism and hypomotility inducement. We assessed the functional status of CORT in 139 mammalian genomes (25 orders), including 30 species of Cetacea. Our findings indicate that cetaceans and other mammals with atypical biorhythms, thermal constraints and/or energy metabolism, have accumulated deleterious mutations in CORT. In light of the pleiotropic action of this neuropeptide, we suggest that this inactivation contributed to a plethora of phenotypic adjustments to accommodate adaptive solutions to specific ecological niches.Competing Interest StatementThe authors have declared no competing interest.