RAMP1

RAMP1

<div class="infobox infobox-gene">
<div class="infobox-header">RAMP1</div>
<div class="infobox-content">
<div class="infobox-row"><strong>Full Name:</strong> Receptor Activity Modifying Protein 1</div>
<div class="infobox-row"><strong>Symbol:</strong> RAMP1</div>
<div class="infobox-row"><strong>Chromosomal Location:</strong> 2q36.1</div>
<div class="infobox-row"><strong>NCBI Gene ID:</strong> 10267</div>
<div class="infobox-row"><strong>Ensembl ID:</strong> ENSG00000132329</div>
<div class="infobox-row"><strong>UniProt ID:</strong> O60883</div>
<div class="infobox-row"><strong>Protein Class:</strong> Single-pass membrane protein, receptor chaperone</div>
<div class="infobox-row"><strong>Associated Diseases:</strong> Migraine, Alzheimer's Disease, Parkinson's Disease, Stroke</div>
</div>
</div>

Overview

RAMP1 (Receptor Activity Modifying Protein 1) encodes a single-pass membrane protein that functions as an essential chaperone for G protein-coupled receptors (GPCRs). By associating with specific GPCRs, RAMP1 enables the formation of functional receptors for calcitonin gene-related peptide (CGRP), adrenomedullin (AM), and amylin. Located on chromosome 2q36.1 with NCBI Gene ID 10267, RAMP1 is expressed in sensory neurons, the brain, cardiovascular system, and immune cells.

RAMP1

<div class="infobox infobox-gene">
<div class="infobox-header">RAMP1</div>
<div class="infobox-content">
<div class="infobox-row"><strong>Full Name:</strong> Receptor Activity Modifying Protein 1</div>
<div class="infobox-row"><strong>Symbol:</strong> RAMP1</div>
<div class="infobox-row"><strong>Chromosomal Location:</strong> 2q36.1</div>
<div class="infobox-row"><strong>NCBI Gene ID:</strong> 10267</div>
<div class="infobox-row"><strong>Ensembl ID:</strong> ENSG00000132329</div>
<div class="infobox-row"><strong>UniProt ID:</strong> O60883</div>
<div class="infobox-row"><strong>Protein Class:</strong> Single-pass membrane protein, receptor chaperone</div>
<div class="infobox-row"><strong>Associated Diseases:</strong> Migraine, Alzheimer's Disease, Parkinson's Disease, Stroke</div>
</div>
</div>

Overview

RAMP1 (Receptor Activity Modifying Protein 1) encodes a single-pass membrane protein that functions as an essential chaperone for G protein-coupled receptors (GPCRs). By associating with specific GPCRs, RAMP1 enables the formation of functional receptors for calcitonin gene-related peptide (CGRP), adrenomedullin (AM), and amylin. Located on chromosome 2q36.1 with NCBI Gene ID 10267, RAMP1 is expressed in sensory neurons, the brain, cardiovascular system, and immune cells.

RAMP1 has emerged as a significant player in neurodegenerative disease research due to its critical role in CGRP receptor function. CGRP signaling is implicated in [migraine](/diseases/migraine) pathogenesis—a condition with significant comorbidity with neurodegenerative disorders. More recent research suggests potential neuroprotective roles for CGRP/RAMP1 signaling in [Alzheimer's disease](/diseases/alzheimers-disease) and [Parkinson's disease](/diseases/parkinsons-disease), making this receptor system an interesting therapeutic target.

Gene and Protein Structure

Gene Organization

The RAMP1 gene spans approximately 8 kb on chromosome 2q36.1 and contains 6 exons. The gene produces multiple transcript variants, with the canonical isoform encoding a 175-amino acid protein.

Protein Topology

The RAMP1 protein has a simple topology:

• N-terminal extracellular domain: Large extracellular N-terminus (~130 amino acids) that forms the ligand-binding pocket with the GPCR
• Single transmembrane helix: A 22-amino acid hydrophobic transmembrane domain anchoring RAMP1 to the cell membrane
• C-terminal intracellular tail: Short cytoplasmic domain (~10 amino acids)

Receptor Complex Formation

RAMP1 forms functional receptor complexes with:

| Partner Receptor | Resulting Receptor | Primary Ligands |
|------------------|-------------------|------------------|
| CALCR (Calcitonin Receptor) | CGRP Receptor | CGRP |
| CALCRL (Calcitonin Receptor-like Receptor) | CGRP Receptor | CGRP, AM |
| CALCRL + RAMP2/3 | Amylin Receptor | Amylin, CGRP |

Expression Pattern

Tissue Distribution

RAMP1 shows distinctive expression patterns:

• Sensory neurons: Highest expression in trigeminal ganglion and dorsal root ganglia
• Brain: Widespread expression in cortex, hippocampus, cerebellum
• Cardiovascular system: Vascular smooth muscle, endothelial cells
• Immune cells: T cells, B cells, macrophages
• Peripheral organs: Lung, heart, kidney, gastrointestinal tract

Cellular Localization

• Neurons: Cell body and axonal projections
• Glia: Astrocyte expression, microglial expression under inflammatory conditions
• Vascular: Smooth muscle and endothelial cells

Physiological Functions

CGRP Receptor Signaling

RAMP1 is essential for functional CGRP receptor formation:

CGRP (Calcitonin Gene-Related Peptide):

• Potent vasodilator
• Key neurotransmitter in trigeminal pain pathway
• Involved in neurogenic inflammation
• Has neurotrophic and neuroprotective effects

• cAMP/PKA pathway (via Gs)
• MAPK/ERK pathway
• PI3K/Akt pathway

Amylin Receptor Signaling

RAMP1 also enables amylin receptor formation:

• Amylin (IAPP): Horm peptide involved in glucose regulation
• Amylin receptor: Involved in food intake, body weight regulation
• Cross-talk with CGRP signaling

Neuroprotection

RAMP1-mediated signaling provides neuroprotection through:

• Anti-apoptotic signaling (via Akt)
• Antioxidant effects
• Promotion of neurite outgrowth
• Modulation of neuroinflammation

Role in Neurodegenerative Diseases

Migraine

RAMP1 and CGRP are central to [migraine](/diseases/migraine) pathogenesis:

Pathogenic mechanisms:

• CGRP release during migraine attacks
• Trigeminal nerve activation
• Vasodilation of intracranial vessels
• Central sensitization

• CGRP receptor antagonists (gepants)
• CGRP monoclonal antibodies
• RAMP1 modulators in development

Alzheimer's Disease

RAMP1/CGRP signaling has complex roles in [Alzheimer's disease](/diseases/alzheimers-disease):

Neuroprotective effects:

• CGRP reduces beta-amyloid-induced toxicity
• Promotes neuronal survival
• Enhances synaptic plasticity
• Modulates neuroinflammation

• RAMP1 polymorphisms associated with AD risk
• Altered expression in AD brains

• CGRP-based therapies under investigation
• Caution needed due to vascular effects

Parkinson's Disease

RAMP1 involvement in [Parkinson's disease](/diseases/parkinsons-disease) includes:

Amylin receptor signaling:

• Modulates dopaminergic neuron function
• May affect alpha-synuclein aggregation
• Alters glucose metabolism in neurons

• CGRP promotes dopaminergic neuron survival
• May enhance mitochondrial function

Stroke and Cerebral Ischemia

RAMP1/CGRP signaling is protective in stroke:

• CGRP promotes cerebral vasodilation
• Reduces ischemic damage
• Enhances post-stroke recovery

Therapeutic Implications

CGRP-Based Therapies

FDA-approved drugs targeting CGRP pathway:

• Erenumab: CGRP receptor antibody
• Fremanezumab: CGRP antibody
• Galcanezumab: CGRP antibody
• Rimegepant: CGRP receptor antagonist
• Ubrogepant: CGRP receptor antagonist

RAMP1 Modulators

Selective RAMP1 modulators in development:

• Target: Modulate CGRP receptor selectivity
• Approach: Reduce vasodilatory effects while retaining neuroprotection

Challenges

• Vascular side effects of CGRP modulation
• Blood-brain barrier penetration
• Long-term safety considerations

CGRP Receptor Signaling Mechanism

The CGRP receptor formed by RAMP1 + CALCRL is a class B GPCR with unique signaling properties:

Receptor Assembly:

• CALCRL (Calcitonin Receptor-like Receptor) is a GPCR with 7 transmembrane domains
• RAMP1 N-terminal domain (~130 aa) wraps around the GPCR extracellular domain
• Together they create a unique ligand-binding pocket that specifically recognizes CGRP

• Primarily couples to Gs proteins → activates adenylate cyclase → increases cAMP
• Can also couple to Gq → activates PLC → IP3/DAG pathway
• β-arrestin recruitment leads to receptor internalization

Signaling Specificity:

• RAMP1 determines ligand selectivity - with RAMP1, receptor prefers CGRP
• With RAMP2/RAMP3, same CALCRL prefers adrenomedullin
• This makes RAMP1 a critical determinant of receptor pharmacology

Adrenomedullin Signaling

While RAMP1 is best known for CGRP receptor formation, it also participates in adrenomedullin (AM) receptor complexes:

Adrenomedullin (AM):

• Peptide hormone with vasodilatory properties
• Two isoforms: AM1 (AM) and AM2 (intermedin)
• Expressed in brain regions including hypothalamus, cortex, and cerebellum

Physiological Functions:

• Cardiovascular regulation (vasodilation, natriuresis)
• Neuroprotection (anti-excitotoxic effects)
• Anti-inflammatory actions
• Modulation of social behavior

• AM levels altered in AD and PD brains
• AM has protective effects in ischemic stroke models
• AM receptor expression changes in neurodegenerative conditions

Preclinical Models

Genetic Models:

• RAMP1 knockout mice: Reduced CGRP receptor activity, altered pain responses
• RAMP1 transgenic mice: Enhanced CGRP signaling, migraine-like phenotypes
• Conditional knockout models: Brain-specific deletion studies

• Knockout: Reduced neurogenic inflammation, altered nociception
• Overexpression: Increased susceptibility to migraine triggers, enhanced cerebrovascular responses

• Species differences in CGRP receptor pharmacology
• Mouse CGRP differs from human CGRP in receptor interactions
• Migraine phenotypes difficult to model in rodents

Pharmacogenetics

RAMP1 Genetic Variants:

• Single nucleotide polymorphisms (SNPs) in coding and regulatory regions
• Some variants associated with:
• Migraine susceptibility
• CGRP antagonist response
• Cardiovascular side effects

• Pharmacogenetic testing may guide CGRP-targeted therapy selection
• Variant-based dosing strategies under investigation
• Gene-environment interactions in migraine pathogenesis

• rs573862 (promoter region) - associated with migraine without aura
• rs12420501 (3'UTR) - affects mRNA stability
• N89D (coding) - alters RAMP1 trafficking

Clinical Trials

Active and Recent Trials:

| Trial | Therapy | Target | Status |
|-------|---------|--------|--------|
| NCT05316961 | Rimegepant | CGRP R | Phase 4 |
| NCT04817088 | Fremanezumab | CGRP | Phase 3 |
| NCT04416968 | Erenumab | CGRP R | Phase 3 |
| NCT05167094 | Zavegepant | CGRP R | Phase 3 |

Outcome Measures:

• Migraine days reduction
• Response rate (≥50% reduction)
• Quality of life measures
• Safety endpoints

• CGRP levels in CSF and plasma
• RAMP1 expression in peripheral blood cells
• Imaging correlates of treatment response

Drug Development Pipeline

Next-Generation Agents:
| Drug | Type | Company | Stage |
|------|------|---------|-------|
| Atogepant | Gepant | AbbVie | Approved |
| Zavegepant | Gepant | Biohaven | Phase 3 |
| Rimegepant | Gepant | Pfizer | Approved |
| Fremanezumab | mAb | Teva | Approved |

RAMP1-Targeted Approaches:

• Small molecule RAMP1 modulators (preclinical)
• Peptide-based antagonists (research)
• Gene therapy approaches (early stage)

• CGRP + 5-HT1F dual agonists
• CGRP + neurotransmitter modulation
• CGRP + preventive drug combinations

Key Publications

Disease Associations

Top DisGeNET gene-disease associations for this gene are listed below. Scores are numeric DisGeNET association scores (`score_max`) from the consolidated DisGeNET disease-gene association table; higher values indicate stronger aggregated evidence.

| Disease | DisGeNET score | Evidence sources | Supporting PMID count |
|---|---:|---|---:|
| coronary artery disease | 0.003 | LHGDN | 1 |
| hypertension | 0.001 | BeFree | 2 |
| migraine | 0.001 | BeFree | 2 |
| prostate cancer | 0.000 | BeFree | 1 |
| thyroid cancer | 0.000 | BeFree | 1 |

Source: DisGeNET-derived consolidated disease-gene associations (`dhimmel/disgenet`, gene symbol `RAMP1`).

See Also

• [CALCR (Calcitonin Receptor](/genes/calcr)
• [CALCA (Calcitonin Gene](/genes/calca)
• [RAMP2](/genes/ramp2)
• [CGRP Signaling](/mechanisms/cgrp-signaling)
• [Migraine Pathophysiology](/diseases/migraine)
• [Alzheimer's Disease Mechanisms](/diseases/alzheimers-disease)
• [Parkinson's Disease Mechanisms](/diseases/parkinsons-disease)

External Links

• [NCBI Gene: RAMP1](https://www.ncbi.nlm.nih.gov/gene/10267)
• [UniProt: RAMP1](https://www.uniprot.org/uniprot/O60883)
• [HGNC: RAMP1](https://www.genenames.org/data/hgnc_data.php?hgnc_id=9814)
• [Allen Brain Atlas: RAMP1 expression](https://human.brain-map.org/)
• [PubMed: RAMP1 neurodegeneration](https://pubmed.ncbi.nlm.nih.gov/?term=RAMP1+Alzheimer+Parkinson)

References

Pathway Diagram

The following diagram shows the key molecular relationships involving RAMP1 discovered through SciDEX knowledge graph analysis: