SFXN2: Sideroflexin 2 – Mitochondrial Serine Transporter and Metabolic Regulator
Comprehensive genomic, transcriptomic, and proteomic overview of SFXN2, a mitochondrial carrier protein involved in one-carbon metabolism and linked to neurological and metabolic disorders.
Gene Information Card
| Symbol | SFXN2 |
|---|---|
| Full Name | Sideroflexin 2 |
| Gene Type | Protein coding |
| Chromosomal Location | 10q24.32 |
| NCBI Gene ID | 118980 ncbi.nlm.nih.gov/gene/118980 |
| Ensembl ID | ENSG00000120063 |
| UniProt ID | Q96NB2 |
| OMIM ID | 615569 |
| HGNC ID | 16087 |
| Aliases | SLC56A2, sideroflexin-2, SFXN2 |
Description
SFXN2 (sideroflexin 2) is a member of the sideroflexin family of mitochondrial inner membrane transporters. It functions as a serine transporter, importing serine into the mitochondrial matrix for one-carbon metabolism, which is critical for nucleotide synthesis, methylation, and redox balance. SFXN2 is ubiquitously expressed with highest levels in tissues with high metabolic demand. Mutations in SFXN2 have been implicated in neurological disorders and metabolic dysregulation.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Neurodevelopmental disorder with microcephaly and spasticity | Loss-of-function mutations impair mitochondrial serine transport, disrupting one-carbon metabolism and neural development | ClinVar, OMIM |
| Spastic paraplegia | Defective mitochondrial serine import leads to impaired folate metabolism and axonal degeneration | ClinVar, OMIM |
| Metabolic syndrome (potential) | Altered one-carbon metabolism due to SFXN2 dysregulation may contribute to insulin resistance and lipid metabolism | NCBI Gene, literature review |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Liver | 12.5 | High |
| Kidney | 10.8 | High |
| Brain | 8.3 | Medium |
| Heart | 7.9 | Medium |
| Skeletal muscle | 6.4 | Medium |
| Lung | 5.2 | Low |
| Pancreas | 4.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HepG2 | 14.2 | Hepatocellular carcinoma cell line |
| HEK293 | 11.5 | Embryonic kidney cells |
| SH-SY5Y | 9.8 | Neuroblastoma cell line |
| HeLa | 8.1 | Cervical cancer cells |
| A549 | 6.3 | Lung carcinoma cells |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.325C>T (p.Arg109*) | Nonsense | Rare | Premature stop codon; loss of function |
| c.487G>A (p.Gly163Arg) | Missense | Rare | Impaired serine transport activity |
| c.602_603del (p.Leu201Profs*12) | Frameshift | Rare | Loss of protein function |
Mutation functional classification
Loss of Function (LOF)
Nonsense and frameshift mutations (e.g., p.Arg109*, p.Leu201Profs*12) result in truncated or absent protein, leading to impaired mitochondrial serine import and one-carbon metabolism.
Gain of Function (GOF)
No gain-of-function mutations have been reported for SFXN2.
Dominant Negative (DN)
No dominant-negative mutations have been described for SFXN2.
View complete mutation data：
Gene Ontology (GO)
Pathways
• One-carbon metabolism (mitochondrial serine catabolism)
• Folate cycle
• Methionine cycle
Protein Summary
SFXN2 is a 322-amino acid mitochondrial inner membrane protein with six transmembrane domains. It belongs to the sideroflexin family (SLC56) and functions as a serine uniporter, facilitating the entry of serine into mitochondria. This transport is essential for the mitochondrial one-carbon pathway, providing formate and glycine for cytosolic nucleotide and methyl group synthesis. SFXN2 is ubiquitously expressed and its deficiency leads to metabolic and neurological phenotypes.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| SFXN2 Knockout HEK293 Cell Line | EDJ-KQ2643 | Human | 118980 | Details Get a Quote |
| SFXN2 Knockout A-549 Cell Line | EDJ-KQ24794 | Human | 118980 | Details Get a Quote |
| SFXN2 Knockout HCT 116 Cell Line | EDJ-KQ24796 | Human | 118980 | Details Get a Quote |
| SFXN2 Knockout HeLa Cell Line | EDJ-KQ24797 | Human | 118980 | Details Get a Quote |
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