Publications

• Deficiency of terminal ADP-ribose protein glycohydrolase TARG1/C6orf130 in neurodegenerative disease.

  Sharifi R., Morra R., Appel C.D., Tallis M., Chioza B., Jankevicius G., Simpson M.A., Matic I., Ozkan E., Golia B., Schellenberg M.J., Weston R., Williams J.G., Rossi M.N., Galehdari H., Krahn J., Wan A., Trembath R.C., Crosby A.H., Ahel D., Hay R., Ladurner A.G., Timinszky G., Williams R.S., Ahel I.

  Adenosine diphosphate (ADP)-ribosylation is a post-translational protein modification implicated in the regulation of a range of cellular processes. A family of proteins that catalyse ADP-ribosylation reactions are the poly(ADP-ribose) (PAR) polymerases (PARPs). PARPs covalently attach an ADP-ribo ... >> More

  Adenosine diphosphate (ADP)-ribosylation is a post-translational protein modification implicated in the regulation of a range of cellular processes. A family of proteins that catalyse ADP-ribosylation reactions are the poly(ADP-ribose) (PAR) polymerases (PARPs). PARPs covalently attach an ADP-ribose nucleotide to target proteins and some PARP family members can subsequently add additional ADP-ribose units to generate a PAR chain. The hydrolysis of PAR chains is catalysed by PAR glycohydrolase (PARG). PARG is unable to cleave the mono(ADP-ribose) unit directly linked to the protein and although the enzymatic activity that catalyses this reaction has been detected in mammalian cell extracts, the protein(s) responsible remain unknown. Here, we report the homozygous mutation of the c6orf130 gene in patients with severe neurodegeneration, and identify C6orf130 as a PARP-interacting protein that removes mono(ADP-ribosyl)ation on glutamate amino acid residues in PARP-modified proteins. X-ray structures and biochemical analysis of C6orf130 suggest a mechanism of catalytic reversal involving a transient C6orf130 lysyl-(ADP-ribose) intermediate. Furthermore, depletion of C6orf130 protein in cells leads to proliferation and DNA repair defects. Collectively, our data suggest that C6orf130 enzymatic activity has a role in the turnover and recycling of protein ADP-ribosylation, and we have implicated the importance of this protein in supporting normal cellular function in humans. << Less

  EMBO J. 32:1225-1237(2013) [PubMed] [EuropePMC]

• ADP-ribosylhydrolase activity of Chikungunya virus macrodomain is critical for virus replication and virulence.

  McPherson R.L., Abraham R., Sreekumar E., Ong S.E., Cheng S.J., Baxter V.K., Kistemaker H.A., Filippov D.V., Griffin D.E., Leung A.K.

  Chikungunya virus (CHIKV), an Old World alphavirus, is transmitted to humans by infected mosquitoes and causes acute rash and arthritis, occasionally complicated by neurologic disease and chronic arthritis. One determinant of alphavirus virulence is nonstructural protein 3 (nsP3) that contains a h ... >> More

  Chikungunya virus (CHIKV), an Old World alphavirus, is transmitted to humans by infected mosquitoes and causes acute rash and arthritis, occasionally complicated by neurologic disease and chronic arthritis. One determinant of alphavirus virulence is nonstructural protein 3 (nsP3) that contains a highly conserved MacroD-type macrodomain at the N terminus, but the roles of nsP3 and the macrodomain in virulence have not been defined. Macrodomain is a conserved protein fold found in several plus-strand RNA viruses that binds to the small molecule ADP-ribose. Prototype MacroD-type macrodomains also hydrolyze derivative linkages on the distal ribose ring. Here, we demonstrated that the CHIKV nsP3 macrodomain is able to hydrolyze ADP-ribose groups from mono(ADP-ribosyl)ated proteins. Using mass spectrometry, we unambiguously defined its substrate specificity as mono(ADP-ribosyl)ated aspartate and glutamate but not lysine residues. Mutant viruses lacking hydrolase activity were unable to replicate in mammalian BHK-21 cells or mosquito <i>Aedes albopictus</i> cells and rapidly reverted catalytically inactivating mutations. Mutants with reduced enzymatic activity had slower replication in mammalian neuronal cells and reduced virulence in 2-day-old mice. Therefore, nsP3 mono(ADP-ribosyl)hydrolase activity is critical for CHIKV replication in both vertebrate hosts and insect vectors, and for virulence in mice. << Less

  Proc. Natl. Acad. Sci. U.S.A. 114:1666-1671(2017) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.