Unmet NeedDysregulation of ADP-ribosylation, the process of adding ADP-ribose groups onto proteins, has been implicated in the pathogenesis of cancer, viral infection, and neurodegeneration. To date, three drugs that inhibit polyADP-ribose polymerases (PARP) have been approved by the FDA to treat ovarian and other cancers. Though a promising new therapeutic target, enzyme families, including PARP, and the polynucleotides that they synthesize (
i.e., polyADP-ribose [PAR]), remain understudied due to a woeful lack of investigational tools. In response, Johns Hopkins researchers have developed ELTA (
Enzymatic
Labeling of
Terminal
ADP-ribose) to label free or protein-conjugated ADP-ribose monomer and polymers. This new investigational tool will allow for researchers to better understand these polynucleotides and their role in a variety of diseases.
Technology ReviewELTA can serve as a research platform that allows the application of research techniques commonly used in the study of RNA and DNA to the study of PAR. For example, ELTA can fluorescently label PAR for biophysical measurement, radiolabel isolated PAR for the assessment of polymer length, and enrich ADP-ribosylated substrate for identification via mass spectrometry. While PAR radio and fluorescent labelling is currently possible, it requires chemical methods for PAR synthesis and conjugation that most molecular and cellular biology labs do not have access to. Similarly, ELTA can assess polymer length with only trace amounts of labeled PAR polymers compared to the current methods that requires large quantities of PAR polymers that are outside the reach of most academic laboratories. Finally, ELTA method is straightforward, highly efficient and can be complete within 1-2 hours. In this way, ELTA is a flexible research tool that will allow for labs to more effectively study this polynucleotide-like protein modification.
Stage of Development While already shown to be an effective method for investigating PAR, researchers are investigating further applications of ELTA. Besides protein-conjugated ADP-ribose, studies in prokaryotes and eukaryotes have revealed several ADP-ribose derivatives, including O-acetyl-ADP-ribose by the sirtuin deacetylase family, ADP-ribose-1’’-phosphate from tRNA splicing, ADP-ribosylation of the antibiotics rifamycin, as well as the recently discovered DNA ADP-ribosylation. ELTA may, therefore, provide a timely tool for discovering the functions of these various forms of ADP-ribosylation in antibiotic resistance, as well as NAD
+, RNA and DNA metabolism.
Inventors Anthony Leung, Robert McPherson, Yoshinari Ando, Elad Elkayam
Patent Status Provisional application pending
