5'-Nucleotidase Domain Containing Protein 1 (NT5DC1)

While the exact function of the protein encoded by NT5DC1 is not known, it belongs to the 5′-(3′)-deoxyribonucleotidase family. Three cytosolic and one plasma membrane-bound 5′-nucleotidases have been cloned and characterized. Their various substrate specificities suggest widely different functions in nucleotide metabolism. The enzyme, named dNT-2, dephosphorylates specifically the 5-and 2′-(3′)-phosphates of uracil and thymine deoxyribonucleotides. The cDNA of human dNT-2 codes for a 25.9-kDa polypeptide with a typical mitochondrial leader peptide, providing the structural basis for two-step processing during import into the mitochondrial matrix. The deduced amino acid sequence is 52% identical to that of a recently described cytosolic deoxyribonucleotidase (dNT-1).