Abstract
A cDNA clone (SfUCPa) encoding a mitochondrial uncoupling protein (UCP) was isolated from the spadix of skunk cabbage (Symplocarpus foetidus). The cDNA contained an open reading frame of 303 amino acids (predicted molecular weight of 32.6 kDa). The predicted polypeptide had six transmembrane domains, three energy transfer protein motifs and one purine nucleotide binding domain (PNBD), which are characteristic of all known UCPs. The corresponding transcript was expressed only in the spadix and was induced by cold treatment. These results suggest that the putative SfUCPA protein may play an important role in thermogenesis in the spadix of skunk cabbage.
