The uncoupling protein homologues: UCP1, UCP2, UCP3, StUCP and AtUCP.

  title={The uncoupling protein homologues: UCP1, UCP2, UCP3, StUCP and AtUCP.},
  author={D. Ricquier and F. Bouillaud},
  journal={The Biochemical journal},
  volume={345 Pt 2},
Animal and plant uncoupling protein (UCP) homologues form a subfamily of mitochondrial carriers that are evolutionarily related and possibly derived from a proton/anion transporter ancestor. The brown adipose tissue (BAT) UCP1 has a marked and strongly regulated uncoupling activity, essential to the maintenance of body temperature in small mammals. UCP homologues identified in plants are induced in a cold environment and may be involved in resistance to chilling. The biochemical activities and… Expand
UCPs, at the interface between bioenergetics and metabolism.
A similar situation now seems unlikely for UCP2 and UCP3 and while activation of their proton transport has been described its physiological relevance remains uncertain and their influence can be envisaged as a result of another transport pathway that takes place in the absence of activation. Expand
Possible physiological roles of mitochondrial uncoupling proteins--UCPn.
  • P. Ježek
  • Biology, Medicine
  • The international journal of biochemistry & cell biology
  • 2002
Findings on the level of organism and reconstituted recombinant proteins demonstrated that UCPn exhibit a protonophoric function, documented by overexpression in mice, L6 myotubes, INS1 cells, muscle, and yeast, and might be pro-apoptotic as well as anti-APoptotic, depending on transcriptional and biochemical regulation. Expand
Mitochondrial Uncoupling Proteins in Mammals and Plants
Molecular, biochemical, and phylogenic data suggest that UCP2 could be considered as an UCP-prototype, and hypotheses have suggested that they are involved in the general balance of basic energy expenditure, protection from reactive oxygen species, and, in plants, in fruit ripening and seed ontogeny. Expand
UCP2, UCP3, avUCP, what do they do when proton transport is not stimulated? Possible relevance to pyruvate and glutamine metabolism.
Induction of UCP2 expression by glutamine strengthens the proposal that new UCPs could act to determine the choice of mitochondrial substrate, which would obviously have an impact on mitochondrial bioenergetics and ROS production. Expand
The biology of mitochondrial uncoupling proteins.
In comparison to the established uncoupling and thermogenic activities of UCP1, UCP2 and UCP3 appear to be involved in the limitation of free radical levels in cells rather than in physiological uncouplings and thermogenesis. Expand
UCP2, not a physiologically relevant uncoupler but a glucose sparing switch impacting ROS production and glucose sensing.
  • F. Bouillaud
  • Biology, Medicine
  • Biochimica et biophysica acta
  • 2009
A metabolic hypothesis is proposed in which UCP2 acts through a transport distinct of the proton transport, which would allow a cell to remain glycolytic within an aerobic organism and explain the spectacular modifications associated with U CP2 manipulation as well as the uncoupling activity usually called for and which remains elusive in vivo. Expand
Coenzyme Q is an obligatory cofactor for uncoupling protein function
The identification of coenzyme Q (ubiquinone) as a native UCP cofactor is reported, and on addition of CoQ10 to reconstituted UCP1 from inclusion bodies, fatty-acid-dependent H+ transport reached the same rate as with native U CP1. Expand
The role of uncoupling proteins in pathophysiological states.
The emergence of the UCP family has altered the approaches to bioenergetics and stressed the importance of uncoupling respiration in different pathophysiological conditions. Expand
Superoxide activates mitochondrial uncoupling proteins
It is shown that superoxide increases mitochondrial proton conductance through effects on UCP1, UCP2 and UCP3, indicating that the interaction of superoxide with UCPs may be a mechanism for decreasing the concentrations of reactive oxygen species inside mitochondria. Expand
Avian UCP: The Killjoy in the Evolution of the Mitochondrial Uncoupling Proteins
It is shown, here, that the avian class seems to be the only vertebrate lineage lacking two of the UCP1/2/3 homologues present in fish and mammals, and it is suggested that birds have lost U CP1 and UCP2. Expand