Cytokines interact with hematopoietin superfamily receptors and stimulate receptor dimerization. We demonstrate that chemoattractant cytokines (chemokines) also trigger biological responses through receptor dimerization. Functional responses are induced after pairwise crosslinking of chemokine receptors by bivalent agonistic antichemokine receptor mAb, but not by their Fab fragments. Monocyte chemoattractant protein (MCP)-1-triggered receptor dimerization was studied in human embryonic kidney (HEK)-293 cells cotransfected with genes coding for the CCR2b receptor tagged with YSK or Myc sequences. After MCP-1 stimulation, immunoprecipitation with Myc-specific antibodies revealed YSK-tagged receptors in immunoblotting. Receptor dimerization also was validated by chemical crosslinking in both HEK-293 cells and the human monocytic cell line Mono Mac 1. Finally, we constructed a loss-of-function CCR2bY139F mutant that acted as a dominant negative, blocking signaling through the CCR2 wild-type receptor. This study provides functional support for a model in which the MCP-1 receptor is activated by ligand-induced homodimerization, allowing discussion of the similarities between bacterial and leukocyte chemotaxis.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC22345 | PMC |
| http://dx.doi.org/10.1073/pnas.96.7.3628 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Structure and self-association of Arrestin-1.
J Struct Biol
January 2025
Gavin Herbert Eye Institute - Center for Translational Vision Research, Department of Ophthalmology, University of California, Irvine, CA 92697, USA; Department of Chemistry, University of California, Irvine, CA 92697, USA; Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697, USA. Electronic address:
Arrestins halt cell signaling by binding to phosphorylated activated G protein-coupled receptors. Arrestin-1 binds to rhodopsin, arrestin-4 binds to cone opsins, and arrestins-2,3 bind to the rest of GPCRs. In addition, it has been reported that arrestin-1 is functionally expressed in mouse cone photoreceptors.
View Article and Find Full Text PDFSpectrum and carcinogenic properties of thyroglobulin gene fusions in thyroid.
Endocr Relat Cancer
January 2025
A Nikitski, Department of Pathology, University of Pittsburgh, Pittsburgh, 15261, United States.
Approximately 10-20% of thyroid cancers are driven by gene fusions, which activate oncogenic signaling through aberrant overexpression, ligand-independent dimerization, or loss of inhibitory motifs. We identified 13 thyroid tumors with thyroglobulin (TG) gene fusions and aimed to assess their histopathology and the fusions' oncogenic and tumorigenic properties. Of 11 cases with surgical pathology, 82% were carcinomas and 18% noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP).
View Article and Find Full Text PDFStructural and evolutionary insights into the functioning of glycoprotein hormones and their receptors.
Andrology
January 2025
Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York, USA.
The neuroendocrine system that comprises the glycoprotein hormones (GpHs) and their receptors is essential for reproduction and metabolism. Each GpH hormone is an αβ heterodimer of cystine-knot proteins and its cognate receptor is a G-protein coupled receptor (GPCR) distinguished by a large leucine-rich-repeat (LRR) extracellular domain that binds the hormone and a class A GPCR transmembrane domain that signals through an associating heterotrimeric G protein. Hence, the receptors are called LRR-containing GPCRs-LGRs.
View Article and Find Full Text PDFAdvances in the therapeutic potentials of ligands of the apelin receptor APJ.
Eur J Pharmacol
January 2025
Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747 AG Groningen, the Netherlands. Electronic address:
Angiotensin II protein J receptor, APJ, is a type A G protein coupled receptor. Endogenous apelin and elabela peptides stimulate APJ via distinct signalling profiles. A complex signalling map of elabela-stimulated APJ was published in 2022.
View Article and Find Full Text PDFUnlabelled: As the principal lipid transporter in the human brain, apolipoprotein E (ApoE) is tasked with the transport and protection of highly vulnerable lipids required to support and remodel neuronal membranes, in a process that is dependent on ApoE receptors. Human allele variants that encode proteins differing only in the number of cysteine (Cys)-to-arginine (Arg) exchanges (ApoE2 [2 Cys], ApoE3 [1 Cys], ApoE4 [0 Cys]) comprise the strongest genetic risk factor for sporadic Alzheimer's disease (AD); however, the molecular feature(s) and resultant mechanisms that underlie these isoform-dependent effects are unknown. One signature feature of Cys is the capacity to form disulfide (Cys-Cys) bridges, which are required to form disulfide bridge-linked dimers and multimers.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!