RRAS1 Gene

RRAS1 Gene

<table class="infobox infobox-gene">
<tr>
<th class="infobox-header" colspan="2">RRAS1 Gene</th>
</tr>
<tr>
<td class="label">Gene Symbol</td>
<td>RRAS1</td>
</tr>
<tr>
<td class="label">Full Name</td>
<td>Related RAS Viral Oncogene Homolog 1</td>
</tr>
<tr>
<td class="label">Alternative Names</td>
<td>R-Ras1, RRAS, R-RAS1</td>
</tr>
<tr>
<td class="label">Chromosomal Location</td>
<td>19q13.33</td>
</tr>
<tr>
<td class="label">NCBI Gene ID</td>
<td>10539</td>
</tr>
<tr>
<td class="label">Ensembl ID</td>
<td>ENSG00000155070</td>
</tr>
<tr>
<td class="label">UniProt ID</td>
<td>P10301</td>
</tr>
<tr>
<td class="label">OMIM</td>
<td>165090</td>
</tr>
<tr>
<td class="label">Protein Class</td>
<td>Small GTPase; Ras family</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td>Alzheimer's disease, Parkinson's disease, various cancers</td>
</tr>
<tr>
<td class="label">Interactor</td>
<td>Interaction Type</td>
</tr>
<tr>
<td class="label">Integrins (αvβ3, α5β1)</td>
<td>Effector</td>
</tr>
<tr>
<td class="label">PI3K</td>
<td>Effector</td>
</tr>
<tr>
<td class="label">FAK</td>
<td>Effector</td>
</tr>
<tr>
<td class="label">RASGRF1</td>
<td>GEF</td>
</tr>
<tr>
<td class="label">RASGRP1</td>
<td>GEF</td>
</tr>
<tr>
<td class="label">p120GAP</td>
<td>GAP</td>
</tr>
<tr>
<td class="label">NF1</td>
<td>GAP</

RRAS1 Gene

<table class="infobox infobox-gene">
<tr>
<th class="infobox-header" colspan="2">RRAS1 Gene</th>
</tr>
<tr>
<td class="label">Gene Symbol</td>
<td>RRAS1</td>
</tr>
<tr>
<td class="label">Full Name</td>
<td>Related RAS Viral Oncogene Homolog 1</td>
</tr>
<tr>
<td class="label">Alternative Names</td>
<td>R-Ras1, RRAS, R-RAS1</td>
</tr>
<tr>
<td class="label">Chromosomal Location</td>
<td>19q13.33</td>
</tr>
<tr>
<td class="label">NCBI Gene ID</td>
<td>10539</td>
</tr>
<tr>
<td class="label">Ensembl ID</td>
<td>ENSG00000155070</td>
</tr>
<tr>
<td class="label">UniProt ID</td>
<td>P10301</td>
</tr>
<tr>
<td class="label">OMIM</td>
<td>165090</td>
</tr>
<tr>
<td class="label">Protein Class</td>
<td>Small GTPase; Ras family</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td>Alzheimer's disease, Parkinson's disease, various cancers</td>
</tr>
<tr>
<td class="label">Interactor</td>
<td>Interaction Type</td>
</tr>
<tr>
<td class="label">Integrins (αvβ3, α5β1)</td>
<td>Effector</td>
</tr>
<tr>
<td class="label">PI3K</td>
<td>Effector</td>
</tr>
<tr>
<td class="label">FAK</td>
<td>Effector</td>
</tr>
<tr>
<td class="label">RASGRF1</td>
<td>GEF</td>
</tr>
<tr>
<td class="label">RASGRP1</td>
<td>GEF</td>
</tr>
<tr>
<td class="label">p120GAP</td>
<td>GAP</td>
</tr>
<tr>
<td class="label">NF1</td>
<td>GAP</td>
</tr>
</table>

RRAS1 (Related RAS Viral Oncogene Homolog 1), also known as R-Ras1, is a member of the small GTPase superfamily belonging to the R-Ras subfamily of Ras GTPases. Located on chromosome 19q13.33, RRAS1 regulates critical cellular processes including cell adhesion, migration, proliferation, and survival. In the nervous system, RRAS1 plays essential roles in neuronal development, synaptic plasticity, and axonal guidance. Growing evidence links RRAS1 dysfunction to [Alzheimer's disease](/diseases/alzheimers-disease), [Parkinson's disease](/diseases/parkinsons-disease), and various cancers.

Overview

Gene Structure

The RRAS1 gene spans approximately 25 kb and consists of 6 exons encoding a 218-amino acid protein. The gene is highly conserved across mammals and exhibits broad tissue expression with particularly high levels in brain, heart, and vascular tissue.

Protein Structure

RRAS1 shares structural homology with other Ras GTPases:

Function

GTPase Cycle

RRAS1 functions as a molecular switch:

• GTP-bound state — Active, can interact with downstream effectors
• GDP-bound state — Inactive, unable to signal
• GTP hydrolysis — Converted to GDP by intrinsic GTPase activity, accelerated by GAPs (GTase-Activating Proteins)
• GDP/GTP exchange — Stimulated by GEFs (Guanine nucleotide Exchange Factors)

Cell Adhesion and Migration

RRAS1 regulates integrin-mediated adhesion:

• Integrin activation — RRAS1 promotes integrin affinity for extracellular matrix
• FAK signaling — Activates Focal Adhesion Kinase pathway
• Actin cytoskeleton — Modulates actin dynamics at adhesion sites
• Cell migration — Controls directional migration through integrin signaling

Neuronal Functions

In neurons, RRAS1 is critical for:

• Neurite outgrowth — RRAS1 promotes axonal and dendritic extension
• Axonal guidance — Modulates growth cone responses to guidance cues
• Synaptic plasticity — Regulates spine formation and function
• Dendritic spine morphology — Controls spine shape and stability
• Synaptic transmission — Modulates neurotransmitter release

Cell Survival

RRAS1 influences cell survival pathways:

• PI3K/Akt signaling — Activates pro-survival signaling
• MAPK pathway — Modulates cell proliferation
• Apoptosis regulation — Can protect against apoptotic stimuli

Brain Expression

RRAS1 is widely expressed in the brain:

• Cerebral cortex — Pyramidal neurons in layers II-VI
• Hippocampus — CA1-CA3 pyramidal cells, dentate gyrus granule cells
• Cerebellum — Purkinje cells, granule cells
• Basal ganglia — Striatal medium spiny neurons
• Thalamus and hypothalamus — Various neuronal populations
• Olfactory bulb — Mitral and tufted cells
• Peripheral nervous system — Sensory and motor neurons

Cellular Localization

In neurons, RRAS1 localizes to:

• Dendritic shafts and spines
• Axonal compartments
• Growth cones
• Postsynaptic densities
• Presynaptic terminals

Molecular Mechanisms

Signaling Pathways

RRAS1 activates multiple downstream pathways:

• RRAS1 activates PI3K (particularly PI3Kγ)
• Leads to Akt phosphorylation and activation
• Promotes cell survival and growth

• RRAS1 can activate Raf-1 through Ras family cascades
• Promotes cell proliferation and differentiation

• Activates Focal Adhesion Kinase
• Regulates integrin signaling and adhesion

• Can activate RalGEFs
• Affects actin cytoskeleton and vesicle trafficking

Integrin Signaling

RRAS1 is a key regulator of integrin function:

• Inside-out signaling — RRAS1 promotes integrin activation from within
• Affinity modulation — Increases integrin affinity for ligands
• Clustering — Facilitates integrin cluster formation
• Outside-in signaling — Modulates downstream signaling upon ligand binding

Synaptic Plasticity

RRAS1 regulates synaptic changes[@johnson2020]:

• Long-term potentiation (LTP) — Required for LTP in hippocampal neurons
• Long-term depression (LTD) — Modulates LTD mechanisms
• Spine remodeling — Controls actin dynamics in dendritic spines
• AMPA receptor trafficking — Regulates GluA1 subunit trafficking

RRAS1 in Synaptic Function

Activity-dependent RRAS1 signaling is critical for synaptic plasticity:

This pathway is impaired in AD, contributing to memory deficits [@chen2023].

Regulation

RRAS1 activity is tightly regulated:

Guanine Nucleotide Exchange Factors (GEFs)

Multiple GEFs activate RRAS1[yang2019]:

• RASGRF1/2 — Calcium-responsive GEFs
• RASGRP1-4 — Diacylglycerol-regulated GEFs
• SOS1/2 — Can activate RRAS1 in certain contexts

GTPase-Activating Proteins (GAPs)

Several GAPs inactivate RRAS1:

• p120GAP — Classical Ras GAP with activity toward RRAS1
• NF1 — Neurofibromin, tumor suppressor
• RASA1-3 — Synaptic GAPs

Post-translational Modifications

• Farnesylation — C-terminal CAAX motif farnesylation for membrane localization
• Palmitoylation — Additional palmitoylation in some isoforms
• Phosphorylation — Can modulate effector interactions

Disease Associations

Alzheimer's Disease

RRAS1 is implicated in [Alzheimer's disease](/diseases/alzheimers-disease) through multiple mechanisms:

• Amyloid-beta effects — Aβ can alter RRAS1 signaling in neurons
• Synaptic dysfunction — RRAS1 contributes to spine loss in AD
• Tau pathology — RRAS1 may intersect with tau phosphorylation pathways
• Neuronal survival — RRAS1-mediated survival signals are compromised in AD
• Neuroinflammation — RRAS1 regulates microglial migration

Molecular Mechanisms in AD

RRAS1 contributes to Alzheimer's disease through specific molecular pathways:

Parkinson's Disease

RRAS1 may contribute to [Parkinson's disease](/diseases/parkinsons-disease) through[@liu2023][@park2022][@wong2021]:

• Dopaminergic neuron survival — RRAS1 supports nigral neuron viability[@park2022]
• Alpha-synuclein interactions — RRAS1 may be affected by α-syn aggregation[@liu2023]
• Axonal transport — RRAS1 regulates microtubule-based transport
• Mitochondrial function — RRAS1 influences mitochondrial dynamics[@wong2021]

Cancer

Dysregulated RRAS1 signaling is associated with multiple cancers:

• Oncogenic activation — RRAS1 can promote tumor cell proliferation
• Metastasis — RRAS1 enhances cell migration and invasion
• Angiogenesis — RRAS1 contributes to tumor vascularization
• Resistance — RRAS1 can confer resistance to targeted therapies

Other Neurological Conditions

• Amyotrophic lateral sclerosis — RRAS1 in motor neuron function
• Schizophrenia — Altered RRAS1 signaling in prefrontal cortex
• Intellectual disability — RRAS1 mutations in neurodevelopmental disorders

Signaling Mechanisms

Membrane Localization and Trafficking

RRAS1 subcellular localization is tightly regulated:

• Prenylation: C-terminal farnesylation anchors RRAS1 to membranes
• Palmitoylation: Additional lipid modification for specific membrane domains
• Endocytosis: RRAS1 cycles between membrane and cytosolic pools
• Localized signaling: Specific membrane compartments concentrate RRAS1 effectors

Integrin Outside-in Signaling

RRAS1 is crucial for integrin-mediated signaling:

Calcium Signaling Integration

RRAS1 integrates with calcium signaling at synapses:

• NMDA receptor activation: Calcium enters postsynaptic spines
• Calmodulin activation: Calcium binds calmodulin
• RASGRF recruitment: Activated GEFs bind to calcium-calmodulin
• RRAS1 activation: GTP loading onto RRAS1
• Synaptic plasticity: LTP maintenance and spine growth

Neuronal Survival Pathways

RRAS1 promotes neuronal survival through multiple mechanisms:

• Akt activation: RRAS1-PI3K signaling activates Akt
• Bad phosphorylation: Akt phosphorylates pro-apoptotic Bad
• Bcl-2 enhancement: Survival signaling upregulates anti-apoptotic proteins
• Caspase inhibition: Downstream caspase activation is blocked

Therapeutic Implications

RRAS1 is a potential therapeutic target:

Neurodegenerative Diseases

• Small molecule modulators — Develop compounds that enhance RRAS1 survival signaling[@hernandez2023]
• GEF agonists — Promote RRAS1 activation to support neuronal health
• GAP inhibitors — Block excessive RRAS1 inactivation

Cancer Therapeutics

• RRAS1 inhibitors — Target RRAS1 in RRAS1-dependent tumors
• Combination therapy — RRAS1 targeting with standard chemotherapies

Biomarkers

• RRAS1 expression — Potential biomarker for certain cancers
• RRAS1 mutations — May predict treatment response

Interaction Network

RRAS1 interacts with multiple proteins:

See Also

• [Ras GTPases](/mechanisms/ras-gtpases)
• [Integrin Signaling](/mechanisms/integrin-signaling)
• [Synaptic Plasticity](/mechanisms/synaptic-plasticity)
• [Alzheimer's Disease](/diseases/alzheimers-disease)
• [Parkinson's Disease](/diseases/parkinsons-disease)
• [Neuronal Development](/mechanisms/neuronal-development)
• [Axonal Transport](/mechanisms/axonal-transport)

External Links

• [NCBI Gene: RRAS1](https://www.ncbi.nlm.nih.gov/gene/10539)
• [UniProt: RRAS1](https://www.uniprot.org/uniprot/P10301)
• [Ensembl: RRAS1](https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000155070)
• [OMIM: 165090](https://omim.org/entry/165090)
• [Allen Brain Atlas](https://human.brain-map.org/)

References