Detection of brown adipose tissue uncoupling protein mRNA in adult patients by a human genomic probe

Abstract

Studies on human brown adipose tissue require specific molecular probes. A human genomic library has been screened with a complementary DNA corresponding to the uncoupling protein (UCP) of rat brown adipose tissue mitochondria. Two recombinant phages were isolated, carrying genomic sequences of human UCP. From them we have subcloned a 0.5 kilobase fragment. This fragment, H-Ucp-0.5, contained two intronic regions and two exonic regions. Exonic regions encoded a sequence of 84 amino acids which exhibited a strong homology with central domain at rat UCP. The organization of H-Ucp-0.5 was confirmed by SI mapping analysis. A Southern analysis suggested that the gene is single type in the human, as it is in rodents. In Northern analysis experiments, H-Ucp-0.5 detected a specific 1.8 kb mRNA in human brown adipose tissue obtained from six patients with phaeochromocytoma and from one patient with a hibernoma. This molecular probe is a new, sensitive and reliable tool with which to study human brown adipocytes.