Article

Molecular cloning of rat uncoupling protein 2 cDNA and its expression in genetically obese Zucker fatty (fa/fa) rats.

Department of Internal Medicine I, School of Medicine, Oita Medical University, Japan.
Biochimica et Biophysica Acta (impact factor: 4.66). 01/1998; 1389(3):178-86. DOI:10.1016/S0005-2760(97)00188-4
Source: PubMed

ABSTRACT We isolated rat UCP2 cDNA, which has been proposed to play an important role in mammalian thermogenesis and body weight regulation. The nucleotide sequence of the cDNA revealed that the rat UCP2 protein is composed of 309 amino acid residues, and is 99% and 95% identical to the mouse and human proteins, respectively. The molecular weight of rat UCP2, calculated from the predicted amino acid sequence, was 33,369, and the UCP2 protein of this size was detected when the cDNA was expressed in vitro. Northern blot analysis revealed that the corresponding mRNA is approximately 1.7 kb in size, and is expressed in a variety of rat organs, with predominant expression in the heart, lung and spleen. UCP2 mRNA levels in the heart, liver, muscle and epididymal adipose tissue of Zucker fatty (fa/fa) rats were comparable to those in the lean littermates, while ob mRNA level markedly increased in the epididymal adipose tissue of Zucker (fa/fa) rats.

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Keywords

309 amino acid residues
 
95% identical
 
body weight regulation
 
corresponding mRNA
 
lean littermates
 
mammalian thermogenesis
 
molecular weight
 
Northern blot analysis
 
nucleotide sequence
 
ob mRNA level
 
predicted amino acid sequence
 
predominant expression
 
rat organs
 
rat UCP2
 
rat UCP2 cDNA
 
rat UCP2 protein
 
UCP2 mRNA levels
 
UCP2 protein
 
Zucker
 
Zucker fatty