Inactivation of thermogenic UCP1 as a historical contingency in multiple placental mammal clades.

ABSTRACT: Mitochondrial uncoupling protein 1 (UCP1) is essential for nonshivering thermogenesis in brown adipose tissue and is widely accepted to have played a key thermoregulatory role in small-bodied and neonatal placental mammals that enabled the exploitation of cold environments. We map ucp1 sequences from 133 mammals onto a species tree constructed from a ~51-kb sequence alignment and show that inactivating mutations have occurred in at least 8 of the 18 traditional placental orders, thereby challenging the physiological importance of UCP1 across Placentalia. Selection and timetree analyses further reveal that ucp1 inactivations temporally correspond with strong secondary reductions in metabolic intensity in xenarthrans and pangolins, or in six other lineages coincided with a ~30

SUBMITTER: Gaudry MJ 

PROVIDER: S-EPMC5507634 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature