| Structural highlights
Function
GBB1_HUMAN Guanine nucleotide-binding proteins (G proteins) are involved as a modulator or transducer in various transmembrane signaling systems. The beta and gamma chains are required for the GTPase activity, for replacement of GDP by GTP, and for G protein-effector interaction.[1]
Publication Abstract from PubMed
Platelet-activating factor (PAF) is a potent phospholipid mediator crucial in multiple inflammatory and immune responses through binding and activating the PAF receptor (PAFR). However, drug development targeting the PAFR has been limited, partly due to an incomplete understanding of its activation mechanism. Here, we present a 2.9-A structure of the PAF-bound PAFR-G(i) complex. Structural and mutagenesis analyses unveil a specific binding mode of PAF, with the choline head forming cation-pi interactions within PAFR hydrophobic pocket, while the alkyl tail penetrates deeply into an aromatic cleft between TM4 and TM5. Binding of PAF modulates conformational changes in key motifs of PAFR, triggering the outward movement of TM6, TM7, and helix 8 for G protein coupling. Molecular dynamics simulation suggests a membrane-side pathway for PAF entry into PAFR via the TM4-TM5 cavity. By providing molecular insights into PAFR signaling, this work contributes a foundation for developing therapeutic interventions targeting PAF signal axis.
Molecular basis for the activation of PAF receptor by PAF.,Fan W, Xu Y, He X, Luo P, Zhu J, Li J, Wang R, Yuan Q, Wu K, Hu W, Zhao Y, Xu S, Cheng X, Wang Y, Xu HE, Zhuang Y Cell Rep. 2024 Jul 23;43(7):114422. doi: 10.1016/j.celrep.2024.114422. Epub 2024 , Jun 28. PMID:38943642[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Johnston CA, Kimple AJ, Giguere PM, Siderovski DP. Structure of the parathyroid hormone receptor C terminus bound to the G-protein dimer Gbeta1gamma2. Structure. 2008 Jul;16(7):1086-94. PMID:18611381 doi:http://dx.doi.org/10.1016/j.str.2008.04.010
- ↑ Fan W, Xu Y, He X, Luo P, Zhu J, Li J, Wang R, Yuan Q, Wu K, Hu W, Zhao Y, Xu S, Cheng X, Wang Y, Xu HE, Zhuang Y. Molecular basis for the activation of PAF receptor by PAF. Cell Rep. 2024 Jul 23;43(7):114422. PMID:38943642 doi:10.1016/j.celrep.2024.114422
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