Research communication

An uncoupling protein homologue putatively involved in facultative muscle thermogenesis in birds

Serge RAIMBAULT, Sami DRIDI, Frédérique DENJEAN, Joël LACHUER, Elodie COUPLAN, Frédéric BOUILLAUD, André BORDAS, Claude DUCHAMP, Mohamed TAOUIS, Daniel RICQUIER

Abstract

The cDNA of an uncoupling protein (UCP) homologue was obtained by screening a chicken skeletal-muscle library. The predicted 307-amino-acid sequence of avian UCP (avUCP) is 55, 70, 70 and 46% identical with mammalian UCP1, UCP2 and UCP3 and plant UCP respectively. avUCP mRNA expression is restricted to skeletal muscle and its abundance was increased 1.3-fold in a chicken line showing diet-induced thermogenesis, and 3.6- and 2.6-fold in cold-acclimated and glucagon-treated ducklings developing muscle non-shivering thermogenesis respectively. The present data support the implication of avUCP in avian energy expenditure.

  • bioenergetics
  • mitochondria
  • mitochondrial carrier
  • skeletal muscle