DNA catalysts with tyrosine kinase activity.
We show that DNA catalysts (deoxyribozymes, DNA enzymes) can phosphorylate tyrosine residues of peptides. Using in vitro selection, we identified deoxyribozymes that transfer the γ-phosphoryl group from a 5'-triphosphorylated donor (a pppRNA oligonucleotide or GTP) to the tyrosine hydroxyl acceptor of a tethered hexapeptide. Tyrosine kinase deoxyribozymes that use pppRNA were identified from each of N30, N40, and N50 random-sequence pools. Each deoxyribozyme requires Zn(2+), and most additionally require Mn(2+). The deoxyribozymes have little or no selectivity for the amino acid identities near the tyrosine, but they are highly selective for phosphorylating tyrosine rather than serine. Analogous GTP-dependent DNA catalysts were identified and found to have apparent Km(GTP) as low as ∼20 μM. These findings establish that DNA has the fundamental catalytic ability to phosphorylate the tyrosine side chain of a peptide substrate.
Department of Chemistry, University of Illinois at Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801, United States.
Shannon M
SM
Walsh
Amit
A
Sachdeva
Scott K
SK
Silverman
D021881:DNA, Catalytic / Q000378:metabolism*; D006160:Guanosine Triphosphate / Q000378:metabolism; D009841:Oligonucleotides / Q000378:metabolism; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D012313:RNA / Q000378:metabolism; D014443:Tyrosine / Q000378:metabolism
D021881:DNA, Catalytic; D009841:Oligonucleotides; D014443:Tyrosine; D012313:RNA; D006160:Guanosine Triphosphate; D011505:Protein-Tyrosine Kinases