PapersFlow Research Brief
Receptor Mechanisms and Signaling
Research Guide
What is Receptor Mechanisms and Signaling?
Receptor mechanisms and signaling refer to the molecular processes by which cell surface or intracellular receptors detect extracellular ligands, undergo conformational changes, and transduce signals into cellular responses through associated proteins such as G proteins or nuclear receptors.
The field encompasses over 106,510 works analyzing ligand binding, receptor activation, and downstream signaling pathways. Key studies include structural determination of G protein-coupled receptors like rhodopsin and computational tools for ligand-receptor characterization. Research spans enzymatic assays, vasoconstrictor discovery, and nuclear receptor superfamilies, with applications in pharmacology and disease.
Research Sub-Topics
G Protein-Coupled Receptor Activation Mechanisms
Investigates conformational changes, allosteric communication, and G protein coupling using crystallography and spectroscopy. Studies biased agonism and signaling selectivity.
Nuclear Receptor Coactivator Recruitment
Examines LXXLL motif interactions with AF-2 domains and histone acetyltransferase activity regulation. Research identifies coregulator selectivity determinants.
Receptor-Ligand Binding Kinetics
Measures association/dissociation rates using surface plasmon resonance and fluorescence correlation spectroscopy. Kinetic mapping predicts drug residence time and efficacy.
GPCR Dimerization and Oligomerization
Studies homo- and heterodimer interfaces, functional allostery, and pharmacological chaperoning effects. FRET and BRET quantify oligomer stoichiometry in native membranes.
Receptor Tyrosine Kinase Downstream Signaling
Maps MAPK, PI3K/Akt, and PLCγ cascades with phosphoproteomics and mathematical modeling. Studies feedback inhibition and signal crosstalk in cancer contexts.
Why It Matters
Receptor mechanisms and signaling underpin drug development targeting GPCRs, which mediate responses to ligands like endothelin discovered by Yanagisawa et al. (1988) in "A novel potent vasoconstrictor peptide produced by vascular endothelial cells," influencing vascular tone and hypertension therapies. Palczewski et al. (2000) in "Crystal Structure of Rhodopsin: A G Protein-Coupled Receptor" provided the first GPCR structure, enabling docking methods refined by Friesner et al. (2006) in "Extra Precision Glide: Docking and Scoring Incorporating a Model of Hydrophobic Enclosure for Protein−Ligand Complexes," which improved binding affinity predictions for over 6,630 citations' worth of protein-ligand complexes. Recent structural insights into SARS-CoV-2 binding to ACE2 by Yan et al. (2020) in "Structural basis for the recognition of SARS-CoV-2 by full-length human ACE2" directly informed COVID-19 interventions, while nuclear receptor work by Mangelsdorf et al. (1995) in "The nuclear receptor superfamily: The second decade" supports endocrine therapies.
Reading Guide
Where to Start
"Crystal Structure of Rhodopsin: A G Protein-Coupled Receptor" by Palczewski et al. (2000), as it provides the foundational atomic structure of a GPCR, essential for understanding receptor mechanisms before advancing to signaling complexity.
Key Papers Explained
Palczewski et al. (2000) in "Crystal Structure of Rhodopsin: A G Protein-Coupled Receptor" established GPCR architecture, enabling Friesner et al. (2006) in "Extra Precision Glide: Docking and Scoring Incorporating a Model of Hydrophobic Enclosure for Protein−Ligand Complexes" to develop docking tools incorporating hydrophobic enclosure for binding predictions. Munson and Rodbard (1980) in "LIGAND: A versatile computerized approach for characterization of ligand-binding systems" provided quantitative analysis methods that complement these structures. Yanagisawa et al. (1988) in "A novel potent vasoconstrictor peptide produced by vascular endothelial cells" exemplified functional signaling via GPCR-like endothelin receptors, while Mangelsdorf et al. (1995) in "The nuclear receptor superfamily: The second decade" extended mechanisms to intracellular receptors.
Paper Timeline
Most-cited paper highlighted in red. Papers ordered chronologically.
Advanced Directions
Recent preprints focus on GPCR biased signaling, such as "Ligand-specific activation trajectories dictate GPCR signalling in cells" and "The molecular basis of μ-opioid receptor signaling plasticity," using cryo-EM to map intermediate states and plasticity. News highlights allosteric modulators in "Designing allosteric modulators to change GPCR G protein subtype selectivity" and peptide ligand mechanisms in "Structural insights into GPCR signaling activated by peptide ligands: from molecular mechanism to therapeutic application."
Papers at a Glance
| # | Paper | Year | Venue | Citations | Open Access |
|---|---|---|---|---|---|
| 1 | Relationship between the inhibition constant (KI) and the conc... | 1973 | Biochemical Pharmacology | 12.8K | ✕ |
| 2 | A novel potent vasoconstrictor peptide produced by vascular en... | 1988 | Nature | 10.7K | ✕ |
| 3 | Enzymatic Determination of Total Serum Cholesterol | 1974 | Clinical Chemistry | 9.1K | ✓ |
| 4 | LIGAND: A versatile computerized approach for characterization... | 1980 | Analytical Biochemistry | 8.5K | ✕ |
| 5 | The nuclear receptor superfamily: The second decade | 1995 | Cell | 6.9K | ✓ |
| 6 | Extra Precision Glide: Docking and Scoring Incorporating a Mo... | 2006 | Journal of Medicinal C... | 6.6K | ✕ |
| 7 | Validation of open : closed arm entries in an elevated plus-ma... | 1985 | Journal of Neuroscienc... | 5.7K | ✕ |
| 8 | The Endophenotype Concept in Psychiatry: Etymology and Strateg... | 2003 | American Journal of Ps... | 5.6K | ✕ |
| 9 | Crystal Structure of Rhodopsin: A G Protein-Coupled Receptor | 2000 | Science | 5.6K | ✕ |
| 10 | Structural basis for the recognition of SARS-CoV-2 by full-len... | 2020 | Science | 5.5K | ✓ |
In the News
Ligand-specific activation trajectories dictate GPCR signalling in cells
conformational equilibria may open new avenues for GPCR drug discovery.
Designing allosteric modulators to change GPCR G protein subtype selectivity
G-protein-coupled receptors (GPCRs) convert extracellular signals into intracellular responses by signalling through 16 subtypes of Gα proteins and two β-arrestin proteins. Biased compounds—molecul...
Structural insights into GPCR signaling activated by peptide ligands: from molecular mechanism to therapeutic application
Recent advances in structural biology have profoundly enhanced our understanding of G protein-coupled receptors (GPCRs), providing detailed molecular insights into their activation and ligand recog...
The molecular basis of μ-opioid receptor signaling plasticity
## Abstract
Molecular basis of ligand binding and receptor activation at the human A 3 adenosine receptor
pharmacology and establishes a foundation for developing more selective therapeutics for various disorders, including inflammatory diseases, cancer, and glaucoma.
Code & Tools
LIANA enables the use of any combination of ligand-receptor methods and resources, and their consensus. The faster, memory-efficient, and more comp...
CellChat is an R package designed for inference, analysis, and visualization of cell-cell communication from single-cell data. CellChat aims to ena...
NICHES is a simple but powerful computational toolset to analyze cell-cell signaling at the single-cell level. NICHES creates unique one-to-one pai...
The main goal of the MultiNicheNet package is to find which ligand-receptor interactions are differentially expressed and differentially active bet...
scMLnet is an R package developed to construct inter-/intracellular multilayer singaling network based on single-cell RNA-seq expression data. scML...
Recent Preprints
Ligand-specific activation trajectories dictate GPCR signalling in cells
Activation of cell surface receptors by extracellular ligands is the hallmark of cell–cell communication and controls most physiological functions in humans. GPCRs are the largest class of such rec...
The molecular basis of μ-opioid receptor signaling plasticity
Activation of the μ-opioid receptor (μOR) alleviates pain but also elicits adverse effects through diverse G proteins and β-arrestins. The structural details of μOR complexes with Gzand β-arrestins...
Designing allosteric modulators to change GPCR G protein subtype selectivity
G-protein-coupled receptors (GPCRs) convert extracellular signals into intracellular responses by signalling through 16 subtypes of Gα proteins and two β-arrestin proteins. Biased compounds—molecul...
Non-equilibrium snapshots of ligand efficacy at the μ-opioid receptor
Distinct ligands for the same G-protein coupled receptor (GPCR) activate intracellular signaling partners to varying extents, but the molecular mechanisms driving these differences remain elusive. ...
Structural and dynamic insights into the biased signaling mechanism of the human kappa opioid receptor
The κ-opioid receptor (KOR) is a member of the G protein-coupled receptor (GPCR) family, modulating cellular responses through transducers such as G proteins and β-arrestins. G-protein-biased KOR a...
Latest Developments
Recent developments in Receptor Mechanisms and Signaling research include the upcoming Gordon Research Conference in February 2026 focusing on photosensory receptors and signal transduction, highlighting cutting-edge research in photoreceptors and optogenetics (GRC Conference). Additionally, advances in understanding GPCR signaling, including ligand-specific activation trajectories and biased signaling, are being actively studied, with recent publications exploring structural and mechanistic insights into GPCR function and therapeutic targeting (Nature, 2026, Science Direct).
Sources
Frequently Asked Questions
What is the relationship between inhibition constant KI and I50 in receptor assays?
Cheng and Prusoff (1973) in "Relationship between the inhibition constant (KI) and the concentration of inhibitor which causes 50 per cent inhibition (I50) of an enzymatic reaction" derived the formula KI = I50 / (1 + [S]/Km), correcting for substrate concentration effects in ligand-binding studies. This equation standardizes inhibitor potency measurements across enzymatic reactions involving receptors. It has been cited 12,805 times for accurate pharmacological analysis.
How do GPCRs transduce signals from ligands?
GPCRs like rhodopsin feature seven transmembrane α-helices that bind ligands and activate G proteins, as shown in the crystal structure by Palczewski et al. (2000) in "Crystal Structure of Rhodopsin: A G Protein-Coupled Receptor." Ligand binding induces conformational changes propagating signals intracellularly. This mechanism applies to diverse stimuli and has 5,575 citations.
What methods characterize ligand-binding systems?
Munson and Rodbard (1980) developed LIGAND, a computerized approach for analyzing ligand-receptor interactions through nonlinear least-squares fitting of binding data, cited 8,490 times. It handles complex models including multiple ligands and sites. The tool remains foundational for quantitative receptor studies.
What defines the nuclear receptor superfamily?
Mangelsdorf et al. (1995) in "The nuclear receptor superfamily: The second decade" cataloged over 50 members regulating gene expression via ligand binding, with 6,937 citations. These receptors control development, metabolism, and reproduction. Advances revealed structural homologies across species.
How was endothelin discovered as a vasoconstrictor?
Yanagisawa et al. (1988) in "A novel potent vasoconstrictor peptide produced by vascular endothelial cells" identified endothelin-1 from porcine aortic endothelium, exhibiting potent vasoconstriction via receptor signaling. The peptide has 21 amino acids and marked potency. It has 10,748 citations and reshaped vascular biology.
What structural insights exist for SARS-CoV-2 receptor binding?
Yan et al. (2020) in "Structural basis for the recognition of SARS-CoV-2 by full-length human ACE2" resolved the spike-ACE2 complex at atomic resolution, revealing key contacts for viral entry. This informed neutralizing antibody design. The work received 5,531 citations amid the pandemic.
Open Research Questions
- ? How do ligand-specific activation trajectories determine GPCR signaling outcomes in cells?
- ? What structural features underlie μ-opioid receptor signaling plasticity with Gz and β-arrestins?
- ? How can allosteric modulators alter GPCR selectivity for specific G protein subtypes?
- ? What non-equilibrium intermediates capture ligand efficacy differences at the μ-opioid receptor?
- ? What dynamic mechanisms drive biased signaling in the human kappa opioid receptor?
Recent Trends
Preprints from the last six months emphasize cryo-EM structures of opioid receptors, including "The molecular basis of μ-opioid receptor signaling plasticity" detailing μOR–Gz and μOR–βarr1 complexes, and "Structural and dynamic insights into the biased signaling mechanism of the human kappa opioid receptor" (2025-10-28) analyzing G-protein bias.
2025-11-07Ligand-specific GPCR trajectories appear in "Ligand-specific activation trajectories dictate GPCR signalling in cells" , shifting focus from static structures to dynamic, biased pathways.
2026-01-14Allosteric modulation for G protein selectivity is explored in "Designing allosteric modulators to change GPCR G protein subtype selectivity" , building on 16 Gα subtypes.
2025-10-22Research Receptor Mechanisms and Signaling with AI
PapersFlow provides specialized AI tools for your field researchers. Here are the most relevant for this topic:
AI Literature Review
Automate paper discovery and synthesis across 474M+ papers
Deep Research Reports
Multi-source evidence synthesis with counter-evidence
Paper Summarizer
Get structured summaries of any paper in seconds
AI Academic Writing
Write research papers with AI assistance and LaTeX support
Start Researching Receptor Mechanisms and Signaling with AI
Search 474M+ papers, run AI-powered literature reviews, and write with integrated citations — all in one workspace.