| Structural highlights
6k2d is a 2 chain structure with sequence from "shigella_paradysenteriae"_weldin_1927 "shigella paradysenteriae" weldin 1927 and Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Gene: | GBP1 (HUMAN), ipaH9.8, CP0226, pWR501_0234, SFLP090 ("Shigella paradysenteriae" Weldin 1927) |
| Activity: | RING-type E3 ubiquitin transferase, with EC number 2.3.2.27 |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[GBP1_HUMAN] Hydrolyzes GTP to GMP in two consecutive cleavage reactions. Exhibits antiviral activity against influenza virus. Promote oxidative killing and deliver antimicrobial peptides to autophagolysosomes, providing broad host protection against different pathogen classes.[1] [IPA9_SHIFL] Effector proteins function to alter host cell physiology and promote bacterial survival in host tissues. This protein is an E3 ubiquitin ligase that interferes with host's ubiquitination pathway and modulates the acute inflammatory responses, thus facilitating bacterial colonization within the host cell. Interacts with IKBKG (NEMO) and TNIP1 (ABIN-1), an ubiquitin-binding adapter protein, which results in TNIP1-dependent 'Lys-27'-linked polyubiquitination of IKBKG. Consequently, polyubiquitinated IKBKG undergoes proteasome-dependent degradation, which perturbs NF-kappa-B activation during bacterial infection. Uses UBE2D2 (UBCH5B) as an E2 ubiquitin-conjugating enzyme.[2] [3] [4]
Publication Abstract from PubMed
The guanylate-binding proteins (GBPs) belong to the dynamin superfamily of GTPases and function in cell-autonomous defense against intracellular pathogens. IpaH9.8, an E3 ligase from the pathogenic bacterium Shigella flexneri, ubiquitinates a subset of GBPs and leads to their proteasomal degradation. Here we report the structure of a C-terminally truncated GBP1 in complex with the IpaH9.8 Leucine-rich repeat (LRR) domain. IpaH9.8LRR engages the GTPase domain of GBP1, and differences in the Switch II and alpha3 helix regions render some GBPs such as GBP3 and GBP7 resistant to IpaH9.8. Comparisons with other IpaH structures uncover interaction hot spots in their LRR domains. The C-terminal region of GBP1 undergoes a large rotation compared to previously determined structures. We further show that the C-terminal farnesylation modification also plays a role in regulating GBP1 conformation. Our results suggest a general mechanism by which the IpaH proteins target their cellular substrates and shed light on the structural dynamics of the GBPs.
Structural mechanism for guanylate-binding proteins (GBPs) targeting by the Shigella E3 ligase IpaH9.8.,Ji C, Du S, Li P, Zhu Q, Yang X, Long C, Yu J, Shao F, Xiao J PLoS Pathog. 2019 Jun 19;15(6):e1007876. doi: 10.1371/journal.ppat.1007876., eCollection 2019 Jun. PMID:31216343[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Nordmann A, Wixler L, Boergeling Y, Wixler V, Ludwig S. A new splice variant of the human guanylate-binding protein 3 mediates anti-influenza activity through inhibition of viral transcription and replication. FASEB J. 2012 Mar;26(3):1290-300. doi: 10.1096/fj.11-189886. Epub 2011 Nov 21. PMID:22106366 doi:http://dx.doi.org/10.1096/fj.11-189886
- ↑ Okuda J, Toyotome T, Kataoka N, Ohno M, Abe H, Shimura Y, Seyedarabi A, Pickersgill R, Sasakawa C. Shigella effector IpaH9.8 binds to a splicing factor U2AF(35) to modulate host immune responses. Biochem Biophys Res Commun. 2005 Jul 29;333(2):531-9. PMID:15950937 doi:10.1016/j.bbrc.2005.05.145
- ↑ Rohde JR, Breitkreutz A, Chenal A, Sansonetti PJ, Parsot C. Type III secretion effectors of the IpaH family are E3 ubiquitin ligases. Cell Host Microbe. 2007 Mar 15;1(1):77-83. PMID:18005683 doi:10.1016/j.chom.2007.02.002
- ↑ Ashida H, Kim M, Schmidt-Supprian M, Ma A, Ogawa M, Sasakawa C. A bacterial E3 ubiquitin ligase IpaH9.8 targets NEMO/IKKgamma to dampen the host NF-kappaB-mediated inflammatory response. Nat Cell Biol. 2010 Jan;12(1):66-73; sup pp 1-9. doi: 10.1038/ncb2006. Epub 2009 , Dec 13. PMID:20010814 doi:10.1038/ncb2006
- ↑ Ji C, Du S, Li P, Zhu Q, Yang X, Long C, Yu J, Shao F, Xiao J. Structural mechanism for guanylate-binding proteins (GBPs) targeting by the Shigella E3 ligase IpaH9.8. PLoS Pathog. 2019 Jun 19;15(6):e1007876. doi: 10.1371/journal.ppat.1007876., eCollection 2019 Jun. PMID:31216343 doi:http://dx.doi.org/10.1371/journal.ppat.1007876
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