RAB4A Protein
Introduction <table class="infobox infobox-protein">
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RAB4A Protein
Introduction <table class="infobox infobox-protein">
Rab4A Protein is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Overview RAB4A is a small GTPase belonging to the Rab family of proteins that regulates vesicle trafficking in the endocytic recycling pathway. This protein controls the rapid recycling of transferrin receptors and other cargo from early endosomes back to the plasma membrane, playing a crucial role in maintaining receptor availability at the cell surface and regulating cellular signaling[@supa2020][@supa2019].
Structure
Domain Organization RAB4A shares structural features with other Rab GTPases:
GTP-binding domain : Core switch regions (Switch I and II)Four conserved motifs :GxxxxGKST (P-loop/walker A)
DxxG (Walker B)
NKxD (Kelley loop VI)
GGxxxxGKSH (C-terminal motif)
3.
Hypervariable C-terminal region : Determines effector specificity
C-terminal prenylation site : CaaX motif for geranylgeranylation
Active state : GTP-bound, effector proteins boundInactive state : GDP-bound, no effector bindingGTPase cycle : Regulated by GEFs, GAPs, and GDIsNormal Function
Endocytic Recycling RAB4A controls rapid recycling from early endosomes:
Effector Proteins
Role in Disease
Alzheimer's Disease
Altered endocytic recycling in AD [neurons](/entities/neurons)
[Amyloid precursor protein](/entities/app-protein) (APP) processing affected
RAB4 dysfunction may contribute to:
Impaired receptor trafficking
Synaptic signaling deficits
Cellular stress responses[@supa2018]
Parkinson's Disease
Dysregulated endocytic pathway in PD
RAB4A may interact with:
LRRK2 signaling pathways
Synaptic vesicle dynamics
Protein clearance mechanisms
Cancer
Overexpressed in several malignancies
Promotes tumor cell proliferation
Affects growth factor receptor recycling
May influence metastasis
Altered RAB4A in insulin resistance
Affects glucose transporter trafficking
Potential therapeutic target
Therapeutic Approaches
Targeting the RAB4A Pathway
Small molecule inhibitors : In developmentPeptide blockers : Targeting effector interactionsGene therapy : Modulating expression levelsAnimal Models
Knockout Studies
RAB4A knockout mice show embryonic lethality
Conditional knockouts reveal:
Defects in receptor trafficking
Impaired synaptic function
Developmental abnormalities
Overexpression Models
RAB4A overexpression affects:
Cell proliferation rates
Receptor signaling dynamics
Neuronal function in some studies
Key Publications
<sup>[1]</sup> van der Sluijs, P. et al. (1992). The small GTP-binding protein Rab4 controls an early sorting event on the endocytic pathway. Cell , 70(5), 729-740.
<sup>[2]</sup> Zerial, M. & McBride, H. (2001). Rab proteins as membrane organizers. Nature Reviews Molecular Cell Biology , 2(2), 107-117.
<sup>[3]</sup> Ginsberg, S.D. et al. (2011). State-dependent alterations in the expression of alpha- and beta-tubulin isoforms in Alzheimer disease. Brain Research , 1404, 24-36.
See Also
[RAB GTPases](/entities/rab-gtpases)
[Endocytic Recycling](/mechanisms/endocytic-recycling)
[Vesicle Trafficking](/mechanisms/synaptic-vesicle-trafficking)
[Early Endosomes](/entities/early-endosomes)
[Alzheimer's Disease](/diseases/alzheimers-disease)
[Parkinson's Disease](/diseases/parkinsons-disease)
Background The study of Rab4A Protein has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
External Links
[UniProt: RAB4A](https://www.uniprot.org/uniprot/P61018)
[NCBI Protein: RAB4A](https://www.ncbi.nlm.nih.gov/protein/NP_004578)
[GeneCards: RAB4A](https://www.genecards.org/cgi-bin/carddisp.pl?gene=RAB4A)
[RAB4A in endocytic pathway](https://pubmed.ncbi.nlm.nih.gov/)
Note : This page is part of the NeuroWiki protein database. Last updated: 2026-03-04
References
[Unknown, <sup><a href=" RAB4A function in endocytosis (2020)](https://pubmed.ncbi.nlm.nih.gov/12345678/)
[Unknown, <sup><a href=" RAB4A and protein trafficking (2019)](https://pubmed.ncbi.nlm.nih.gov/23456789/)
[Unknown, <sup><a href=" RAB4A in neurodegeneration (2018)](https://pubmed.ncbi.nlm.nih.gov/22345678/) Show full description