8h8j
From Proteopedia
Lodoxamide-bound GPR35 in complex with G13
Structural highlights
FunctionGNA13_HUMAN Guanine nucleotide-binding proteins (G proteins) are involved as modulators or transducers in various transmembrane signaling systems (PubMed:15240885, PubMed:16787920, PubMed:16705036, PubMed:27084452). Activates effector molecule RhoA by binding and activating RhoGEFs (ARHGEF1/p115RhoGEF, ARHGEF11/PDZ-RhoGEF and ARHGEF12/LARG) (PubMed:15240885, PubMed:12515866). GNA13-dependent Rho signaling subsequently regulates transcription factor AP-1 (activating protein-1) (By similarity). Promotes tumor cell invasion and metastasis by activating RhoA/ROCK signaling pathway (PubMed:16787920, PubMed:16705036, PubMed:27084452). Inhibits CDH1-mediated cell adhesion in process independent from Rho activation (PubMed:11976333).[UniProtKB:P27601][1] [2] [3] [4] [5] [6] Publication Abstract from PubMedEndogenous ions play important roles in the function and pharmacology of G protein-coupled receptors (GPCRs) with limited atomic evidence. In addition, compared with G protein subtypes G(s), G(i/o), and G(q/11), insufficient structural evidence is accessible to understand the coupling mechanism of G(12/13) protein by GPCRs. Orphan receptor GPR35, which is predominantly expressed in the gastrointestinal tract and is closely related to inflammatory bowel diseases (IBDs), stands out as a prototypical receptor for investigating ionic modulation and G(13) coupling. Here we report a cryo-electron microscopy structure of G(13)-coupled GPR35 bound to an anti-allergic drug, lodoxamide. This structure reveals a novel divalent cation coordination site and a unique ionic regulatory mode of GPR35 and also presents a highly positively charged binding pocket and the complementary electrostatic ligand recognition mode, which explain the promiscuity of acidic ligand binding by GPR35. Structural comparison of the GPR35-G(13) complex with other G protein subtypes-coupled GPCRs reveals a notable movement of the C-terminus of alpha5 helix of the Galpha(13) subunit towards the receptor core and the least outward displacement of the cytoplasmic end of GPR35 TM6. A featured 'methionine pocket' contributes to the G(13) coupling by GPR35. Together, our findings provide a structural basis for divalent cation modulation, ligand recognition, and subsequent G(13) protein coupling of GPR35 and offer a new opportunity for designing GPR35-targeted drugs for the treatment of IBDs. Insights into divalent cation regulation and G(13)-coupling of orphan receptor GPR35.,Duan J, Liu Q, Yuan Q, Ji Y, Zhu S, Tan Y, He X, Xu Y, Shi J, Cheng X, Jiang H, Eric Xu H, Jiang Y Cell Discov. 2022 Dec 21;8(1):135. doi: 10.1038/s41421-022-00499-8. PMID:36543774[7] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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Categories: Homo sapiens | Large Structures | Mus musculus | Duan J | Jiang Y | Liu Q | Xu HE | Yuan Q
