FABP6 (Fatty Acid Binding Protein 6)
Ileal Bile Acid Binding Protein: Function, Expression, and Clinical Relevance
Gene Information Card
| Symbol | FABP6 |
|---|---|
| Full Name | Fatty Acid Binding Protein 6 |
| Gene Type | protein-coding |
| Chromosomal Location | 5q33.3 |
| NCBI Gene ID | 2172 ncbi.nlm.nih.gov/gene/2172 |
| Ensembl ID | ENSG00000170231 |
| UniProt ID | P51161 |
| OMIM ID | 600422 |
| HGNC ID | 3560 |
| Aliases | I-BABP, I-BAP, I-BALB, ILBP, I-BABP-L |
Description
FABP6 encodes the ileal bile acid binding protein (I-BABP), a cytosolic protein that binds bile acids and facilitates their enterohepatic circulation. It is primarily expressed in the ileum and plays a key role in bile acid transport and metabolism. The gene is located on chromosome 5q33.3 and is a member of the fatty acid binding protein family.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Crohn's disease | Altered bile acid absorption due to FABP6 dysregulation may contribute to intestinal inflammation. | PMID: 21559391 |
| Primary bile acid malabsorption | Reduced FABP6 expression impairs ileal bile acid uptake, leading to diarrhea and steatorrhea. | PMID: 10419516 |
| Colorectal cancer | FABP6 overexpression may promote tumor growth via bile acid signaling. | PMID: 23666921 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Ileum | 112.5 | High |
| Colon | 8.2 | Medium |
| Small intestine | 45.3 | High |
| Liver | 0.5 | Not detected |
| Kidney | 0.3 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| Caco-2 | 15.6 | Colorectal adenocarcinoma cell line |
| HT-29 | 12.1 | Colorectal adenocarcinoma cell line |
| HCT 116 | 8.9 | Colorectal carcinoma cell line |
| HepG2 | 0.2 | Hepatocellular carcinoma cell line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1A>G (p.Met1?) | Missense | <0.01% | Potential loss of start codon; functional impact unknown |
| c.79C>T (p.Arg27Trp) | Missense | <0.01% | May alter bile acid binding affinity |
| c.292G>A (p.Gly98Ser) | Missense | <0.01% | Reported in ClinVar as uncertain significance |
Mutation functional classification
Loss of Function (LOF)
Mutations that disrupt the start codon or critical binding residues likely reduce bile acid transport capacity.
Gain of Function (GOF)
No gain-of-function mutations have been reported for FABP6.
Dominant Negative (DN)
No dominant-negative mutations have been described for FABP6.
View complete mutation data：
Gene Ontology (GO)
| • bile acid binding | • fatty acid binding |
| • lipid transport | • intracellular lipid transport |
| • cytoplasm |
Pathways
• Bile acid and bile salt metabolism
• Transport of bile salts and organic acids
Protein Summary
The FABP6 protein (I-BABP) is a 14 kDa cytosolic protein that binds bile acids with high affinity. It is expressed predominantly in the ileal enterocytes and facilitates the intracellular transport of bile acids from the apical to the basolateral membrane, contributing to enterohepatic circulation. The protein structure includes a beta-barrel fold typical of fatty acid binding proteins.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| FABP6 Knockout HEK293 Cell Line | EDJ-KQ4575 | Human | 2172 | Details Get a Quote |
| FABP6 Knockout A-549 Cell Line | EDJ-KQ27230 | Human | 2172 | Details Get a Quote |
| FABP6 Knockout HCT 116 Cell Line | EDJ-KQ27231 | Human | 2172 | Details Get a Quote |
| FABP6 Knockout HeLa Cell Line | EDJ-KQ53199 | Human | 2172 | Details Get a Quote |
