RABIF: RAB Interacting Factor
A guanine nucleotide exchange factor (GEF) for Rab small GTPases involved in vesicle trafficking and membrane transport.
Gene Information Card
| Symbol | RABIF |
|---|---|
| Full Name | RAB interacting factor |
| Gene Type | protein-coding |
| Chromosomal Location | 1q42.13 |
| NCBI Gene ID | 5877 ncbi.nlm.nih.gov/gene/5877 |
| Ensembl ID | ENSG00000143106 |
| UniProt ID | P47224 |
| OMIM ID | 603725 |
| HGNC ID | 9798 |
| Aliases | MSS4, RAS-associated protein RAB3A interacting factor, SEC4 |
Description
RABIF (RAB interacting factor) encodes a guanine nucleotide exchange factor (GEF) that specifically activates Rab small GTPases, including RAB3A, RAB8A, and RAB10. The protein facilitates the exchange of GDP for GTP, thereby regulating vesicle trafficking, exocytosis, and membrane transport. RABIF is ubiquitously expressed and plays a critical role in neurotransmitter release and insulin secretion.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Diabetes Mellitus, Type 2 | Impaired RABIF-mediated RAB3A activation may disrupt insulin granule exocytosis in pancreatic beta cells. | PMID: 19056867 |
| Neurodegenerative disorders (Alzheimer's disease) | Altered RABIF expression may affect synaptic vesicle cycling and amyloid precursor protein trafficking. | PMID: 23382691 |
| Cancer (pancreatic, breast) | RABIF overexpression may promote tumor cell proliferation and migration via Rab GTPase dysregulation. | PMID: 25605274 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 12.5 | Medium |
| Pancreas | 8.3 | Medium |
| Liver | 6.1 | Low |
| Heart | 5.4 | Low |
| Kidney | 7.2 | Medium |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK 293 | 14.2 | High expression |
| HeLa | 9.8 | Medium expression |
| SH-SY5Y | 11.5 | High expression |
| MCF7 | 7.6 | Medium expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.287A>G (p.Asn96Ser) | Missense | 0.001% (gnomAD) | Potential loss of GEF activity; not validated in ClinVar |
| c.412C>T (p.Arg138Trp) | Missense | 0.002% (gnomAD) | Unknown functional effect; not reported in COSMIC |
Mutation functional classification
Loss of Function (LOF)
No validated loss-of-function mutations reported in ClinVar or COSMIC for RABIF.
Gain of Function (GOF)
No validated gain-of-function mutations reported.
Dominant Negative (DN)
No validated dominant-negative mutations reported.
View complete mutation data：
Gene Ontology (GO)
Pathways
• RAB3A/RABIF-mediated exocytosis (Reactome: R-HSA-8876198)
• Rab regulation of trafficking (Reactome: R-HSA-9007101)
• Insulin secretion (KEGG: hsa04911)
Protein Summary
RABIF (MSS4) is a 123-amino-acid protein that acts as a guanine nucleotide exchange factor (GEF) for Rab GTPases, particularly RAB3A, RAB8A, and RAB10. It promotes the active GTP-bound state of these Rab proteins, regulating vesicle docking and fusion. The protein is highly conserved and expressed in multiple tissues, with highest levels in brain and pancreas. Structural studies show a compact fold with a conserved GEF domain. Dysregulation of RABIF has been implicated in diabetes and cancer.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| RABIF Knockout HEK293 Cell Line | EDJ-KQ5634 | Human | 5877 | Details Get a Quote |
| RABIF Knockout HCT 116 Cell Line | EDJ-KQ28958 | Human | 5877 | Details Get a Quote |
| RABIF Knockout HeLa Cell Line | EDJ-KQ28959 | Human | 5877 | Details Get a Quote |
| RABIF Knockout A-549 Cell Line | EDJ-KQ27694 | Human | 5877 | Details Get a Quote |
