Linked Life Data

17576568

Source:http://linkedlifedata.com/resource/pubmed/id/17576568

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2007-9-18
pubmed:abstractText
Mammalian uncoupling protein 1 (UCP1) mediates nonshivering thermogenesis in brown adipose tissue. We previously reported on the presence of a UCP1 orthologue in ectothermic fish and observed downregulation of UCP1 gene expression in the liver of the common carp. Neither the function of UCP1, nor the mode of UCP1 activation is known in carp liver mitochondria. Here, we compared the proton conductance at 25 degrees C of liver mitochondria isolated from carp either maintained at 20 degrees C (warm-acclimated, WA) or exposed to 8 degrees C (cold-acclimated, CA) water temperature for 7-10 days. Liver mitochondria from WA carp had higher state four rates of oxygen consumption and greater proton conductance at high membrane potential. Liver mitochondria from WA, but not from CA, carp showed a strong increase in proton conductance when palmitate (or 4-hydroxy-trans-2-nonenal, HNE) was added, and this inducible proton conductance was prevented by addition of GDP. This fatty acid sensitive proton leak is likely due to the expression of UCP1 in the liver of WA carp. The observed biochemical properties of proton leak strongly suggest that carp UCP1 is a functional uncoupling protein with broadly the same activatory and inhibitory characteristics as mammalian UCP1. Significant UCP1 expression was also detected in our previous study in whole brain of the carp. We here observed a twofold increase of UCP1 mRNA in carp brain following cold exposure, suggesting a role of UCP1 in the thermal adaptation of brain metabolism. In situ hybridization located the UCP1 gene expression to the optic tectum responsible for visual system control, the descending trigeminal tract and the solitary tract. Taken together, this study characterises uncoupling protein activity in an ectotherm for the first time.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0174-1578
pubmed:author
pubmed:issnType
Print
pubmed:volume
177
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
743-52
pubmed:dateRevised
2009-6-8
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Functional characterisation of UCP1 in the common carp: uncoupling activity in liver mitochondria and cold-induced expression in the brain.
pubmed:affiliation
Animal Physiology, Department of Biology, Philipps University Marburg, Karl-von-Frisch-Str. 8, Marburg, 35032, Germany. Jastroch@staff.uni-marburg.de
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't