F13B Gene - Coagulation Factor XIII B Subunit
Genetic and Functional Insights into the F13B Gene
Gene Information Card
| Symbol | F13B |
|---|---|
| Full Name | Coagulation Factor XIII B Subunit |
| Gene Type | Protein coding |
| Chromosomal Location | 1q31.3 |
| NCBI Gene ID | 2165 ncbi.nlm.nih.gov/gene/2165 |
| Ensembl ID | ENSG00000143278 |
| UniProt ID | P05160 |
| OMIM ID | 134580 |
| HGNC ID | 3534 |
| Aliases | FXIIIB, FXIII-B, F13B |
Description
The F13B gene encodes the B subunit of coagulation factor XIII (FXIII), a heterotetrameric transglutaminase that stabilizes fibrin clots by cross-linking fibrin chains. The B subunit serves as a carrier for the catalytic A subunit in plasma, protecting it from proteolysis and regulating its activation. F13B is primarily expressed in the liver and secreted into the bloodstream. Mutations in F13B can lead to factor XIII deficiency, a rare autosomal recessive bleeding disorder characterized by impaired clot stability and delayed bleeding.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Factor XIII Deficiency (B Subunit Type) | Loss-of-function mutations in F13B impair the formation of the FXIII-A2B2 complex, reducing FXIII activity and leading to unstable fibrin clots. | ClinVar, OMIM |
| Bleeding Disorder Due to FXIII Deficiency | Deficiency of FXIII B subunit results in reduced plasma FXIII activity, causing prolonged bleeding, poor wound healing, and spontaneous hemorrhage. | OMIM #134580, NCBI |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Liver | 12.5 | High |
| Plasma (secreted) | N/A | High (protein) |
| Kidney | 1.2 | Low |
| Lung | 0.8 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HepG2 | 10.3 | Hepatocyte cell line |
| HEK293 | 0.5 | Low expression |
| K562 | 0.2 | Very low |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1120C>T (p.Arg374Ter) | Nonsense | Rare | Loss of function; premature truncation of B subunit |
| c.1462G>A (p.Gly488Arg) | Missense | Rare | Impaired subunit assembly; reduced FXIII activity |
| c.1978_1980del (p.Phe660del) | Deletion | Rare | Disrupts protein folding; loss of function |
Mutation functional classification
Loss of Function (LOF)
Most F13B mutations are loss-of-function, leading to reduced or absent B subunit, destabilizing the FXIII complex and causing factor XIII deficiency.
Gain of Function (GOF)
No gain-of-function mutations reported in F13B.
Dominant Negative (DN)
No dominant-negative mutations reported; F13B deficiency is autosomal recessive.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Common Pathway of Fibrin Clot Formation (Reactome: R-HSA-140877)
• Formation of Fibrin Clot (Clotting Cascade) (KEGG: hsa04610)
Protein Summary
The coagulation factor XIII B subunit (FXIII-B) is a 641-amino-acid glycoprotein with 10 sushi (CCP) domains. It circulates in plasma as a non-catalytic carrier for the A subunit, forming the FXIII-A2B2 tetramer. FXIII-B protects the A subunit from proteolytic degradation and regulates its activation by thrombin and calcium. The B subunit is synthesized in the liver and secreted. Its absence leads to rapid clearance of the A subunit and severe bleeding diathesis.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| F13B Knockout HEK293 Cell Line | EDJ-KQ4570 | Human | 2165 | Details Get a Quote |
| F13B Knockout HeLa Cell Line | EDJ-KQ53193 | Human | 2165 | Details Get a Quote |
| F13B Knockout A-549 Cell Line | EDJ-KQ61672 | Human | 2165 | Details Get a Quote |
| F13B Knockout HCT 116 Cell Line | EDJ-KQ70155 | Human | 2165 | Details Get a Quote |
