8tlm
Structure of a class A GPCR/Fab complex
Structural highlights
FunctionGFP_AEQVI Energy-transfer acceptor. Its role is to transduce the blue chemiluminescence of the protein aequorin into green fluorescent light by energy transfer. Fluoresces in vivo upon receiving energy from the Ca(2+)-activated photoprotein aequorin.CCR8_HUMAN Receptor for the chemokine CCL1/SCYA1/I-309. May regulate monocyte chemotaxis and thymic cell line apoptosis. Alternative coreceptor with CD4 for HIV-1 infection.[1] [2] [3] [4] Publication Abstract from PubMedThe C-C motif chemokine receptor 8 (CCR8) is a class A G-protein coupled receptor that has emerged as a promising therapeutic target in cancer. Targeting CCR8 with an antibody has appeared to be an attractive therapeutic approach, but the molecular basis for chemokine-mediated activation and antibody-mediated inhibition of CCR8 are not fully elucidated. Here, we obtain an antagonist antibody against human CCR8 and determine structures of CCR8 in complex with either the antibody or the endogenous agonist ligand CCL1. Our studies reveal characteristic antibody features allowing recognition of the CCR8 extracellular loops and CCL1-CCR8 interaction modes that are distinct from other chemokine receptor - ligand pairs. Informed by these structural insights, we demonstrate that CCL1 follows a two-step, two-site binding sequence to CCR8 and that antibody-mediated inhibition of CCL1 signaling can occur by preventing the second binding event. Together, our results provide a detailed structural and mechanistic framework of CCR8 activation and inhibition that expands our molecular understanding of chemokine - receptor interactions and offers insight into the development of therapeutic antibodies targeting chemokine GPCRs. Structural basis of antibody inhibition and chemokine activation of the human CC chemokine receptor 8.,Sun D, Sun Y, Janezic E, Zhou T, Johnson M, Azumaya C, Noreng S, Chiu C, Seki A, Arenzana TL, Nicoludis JM, Shi Y, Wang B, Ho H, Joshi P, Tam C, Payandeh J, Comps-Agrar L, Wang J, Rutz S, Koerber JT, Masureel M Nat Commun. 2023 Dec 1;14(1):7940. doi: 10.1038/s41467-023-43601-8. PMID:38040762[5] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||
