A unique deubiquitinase that deconjugates phosphoribosyl-linked protein ubiquitination
Ubiquitination regulates many aspects of host immunity and thus is a common target for infectious agents. Recent studies revealed that members of the SidE effector family of the bacterial pathogen Legionella pneumophila attacked several small GTPases associated with the endoplasmic reticulum by a novel ubiquitination mechanism that does not require the E1 and E2 enzymes of the host ubiquitination machinery. Following ubiquitin activation by ADP- ribosylation via a mono-ADP-ribosylation motif, ADP-ribosylated ubiquitin is cleaved by a phosphodiesterasedomainwithinSdeA,whichisconcomitantwiththelinkof phosphoribosylated ubiquitin to serine residues in the substrate. Here we demonstrate that the activity of SidEs is regulated by SidJ, another effector encoded by a gene situated in the locus coding for three members of the SidE family (SdeC, SdeB and SdeA). SidJ functions to remove ubiquitin from SidEs-modified substrates by cleaving the phosphodiester bond that links phosphoribosylated ubiquitin to protein substrates. Further, the deubiquitinase activity of SidJ is essential for its role in L. pneumophila infection. Finally, the activity of SidJ is required for efficiently reducing the abundance of ubiquitinated Rab33b in infected cells within a few hours after bacterial uptake. Our results establish SidJ as a deubiquitinase that functions to impose temporal regulation of the activity of the SidE effectors. The identification of SidJ may shed light on future study of signaling cascades mediated by this unique ubiquitination that also potentially regulates cellular processes in eukaryotic cells.
- Research Organization:
- Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 1371993
- Report Number(s):
- PNNL-SA-123995; 49531; 453040220
- Journal Information:
- Cell Research, Journal Name: Cell Research Journal Issue: 7 Vol. 27; ISSN 1001-0602
- Publisher:
- Shanghai Institutes for Biological Sciences
- Country of Publication:
- United States
- Language:
- English
Similar Records
The Legionella Effector SdjA Is a Bifunctional Enzyme That Distinctly Regulates Phosphoribosyl Ubiquitination
Regulation of phosphoribosyl ubiquitination by a calmodulin-dependent glutamylase
Protein polyglutamylation catalyzed by the bacterial calmodulin-dependent pseudokinase SidJ
Journal Article
·
Mon Sep 06 20:00:00 EDT 2021
· mBio (Online)
·
OSTI ID:1839080
Regulation of phosphoribosyl ubiquitination by a calmodulin-dependent glutamylase
Journal Article
·
Thu Aug 15 00:00:00 EDT 2019
· Nature
·
OSTI ID:1572484
Protein polyglutamylation catalyzed by the bacterial calmodulin-dependent pseudokinase SidJ
Journal Article
·
Sun Nov 03 19:00:00 EST 2019
· eLife
·
OSTI ID:1628913