RAB21: A Key Regulator of Endosomal Trafficking and Signaling
Comprehensive genomic and functional overview of the RAB21 gene
Gene Information Card
| Symbol | RAB21 |
|---|---|
| Full Name | RAB21, member RAS oncogene family |
| Gene Type | protein-coding |
| Chromosomal Location | 12q21.2 |
| NCBI Gene ID | 23011 ncbi.nlm.nih.gov/gene/23011 |
| Ensembl ID | ENSG00000135446 |
| UniProt ID | Q9UL25 |
| OMIM ID | 612201 |
| HGNC ID | 18263 |
| Aliases | RAB21, RAB21A, RAB21B |
Description
RAB21 is a member of the RAS oncogene family of small GTPases that regulate intracellular vesicle trafficking, particularly endosomal recycling and signaling. It cycles between an active GTP-bound and inactive GDP-bound state, modulating membrane trafficking, cell adhesion, and receptor signaling. RAB21 is implicated in cancer progression, neurodegenerative disorders, and infectious diseases.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Cancer (multiple types) | Dysregulation of RAB21 alters endosomal trafficking of growth factor receptors, promoting oncogenic signaling | COSMIC, ClinVar |
| Alzheimer's disease | RAB21 may influence amyloid precursor protein trafficking and processing | NCBI Gene, UniProt |
| Infectious diseases (e.g., Salmonella) | RAB21 is hijacked by pathogens to modulate host cell endocytosis | UniProt, PubMed |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 12.5 | Medium |
| Lung | 8.3 | Low |
| Liver | 15.2 | Medium |
| Kidney | 10.1 | Medium |
| Testis | 20.4 | High |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HeLa | 18.7 | Cervical cancer cell line |
| A549 | 14.2 | Lung cancer cell line |
| HEK293 | 22.1 | Embryonic kidney cell line |
| MCF7 | 9.8 | Breast cancer cell line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.437G>A (p.Arg146Gln) | Missense | 0.02% | Alters GTP-binding affinity |
| c.523C>T (p.Arg175Trp) | Missense | 0.01% | Potential loss of function |
| c.689A>G (p.Asn230Ser) | Missense | 0.03% | Unknown significance |
Mutation functional classification
Loss of Function (LOF)
Mutations impairing GTP binding or hydrolysis reduce RAB21 activity, disrupting endosomal trafficking.
Gain of Function (GOF)
Activating mutations (e.g., constitutive GTP-bound state) enhance oncogenic signaling.
Dominant Negative (DN)
Mutants that sequester guanine nucleotide exchange factors (GEFs) can inhibit wild-type RAB21 function.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Endosomal recycling pathway (Reactome: R-HSA-432722)
• RAB regulation of trafficking (Reactome: R-HSA-9007101)
• Signaling by Receptor Tyrosine Kinases (Reactome: R-HSA-9006934)
Protein Summary
RAB21 is a small GTPase (approx. 24 kDa) that localizes to early endosomes and recycling endosomes. It regulates the trafficking of integrins, growth factor receptors, and other cargo, influencing cell migration, adhesion, and proliferation. Post-translational prenylation at its C-terminus is essential for membrane association. RAB21 interacts with multiple effectors, including RABGEF1 and RAB11FIPs, to coordinate endosomal dynamics.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| RAB21 Knockout HEK293 Cell Line | EDJ-KQ7777 | Human | 23011 | Details Get a Quote |
| RAB21 Knockout A-549 Cell Line | EDJ-KQ33254 | Human | 23011 | Details Get a Quote |
| RAB21 Knockout HCT 116 Cell Line | EDJ-KQ33255 | Human | 23011 | Details Get a Quote |
| RAB21 Knockout HeLa Cell Line | EDJ-KQ33256 | Human | 23011 | Details Get a Quote |
