:: infobox .infobox-protein
| FANCL Protein | |
|---|---|
| Gene | FANCL |
| UniProt | Q9NXF1 |
| Molecular Weight | 43 kDa |
| Length | 380 amino acids |
| Cellular Location | Nucleus |
| Protein Family | RING finger E3 ligase |
| Aliases | FA-L, FANCL, E3 ubiquitin ligase |
| Enzymatic Activity | E3 ubiquitin ligase |
===
FANCL is the catalytic E3 ubiquitin ligase subunit of the Fanconi anemia (FA) core complex. It catalyzes the monoubiquitination of FANCD2 and FANCI, the essential activation step in the FA DNA damage response pathway. FANCL contains a RING finger domain that confers E3 ubiquitin ligase activity and works with the E2 conjugating enzyme UBE2T to transfer ubiquitin to FANCD2. Dysregulation of FANCL and the FA pathway has implications for neurodegeneration, cancer predisposition, and therapeutic targeting.
FANCL is a 380-amino acid protein with a molecular weight of approximately 43 kDa. The protein contains several functional domains:
The RING finger domain coordinates two Zn²⁺ ions and catalyzes ubiquitin transfer from the E2 enzyme to the substrate. The UEV domain specifically recognizes UBE2T (E2 conjugating enzyme) and positions it for ubiquitin transfer.
FANCL catalyzes monoubiquitination through:
UBE2T∼Ub + FANCD2 → FANCD2-Ub + UBE2T
FANCL-mediated ubiquitination targets:
FANCL is essential for the FA DNA damage response:
FANCL is a component of the FA core complex (8 proteins):
| Component | Function |
|---|---|
| FANCA | Scaffold protein |
| FANCB | Structural component |
| FANCC | Signal transduction |
| FANCL | E3 ubiquitin ligase ✓ |
| FANCM | DNA translocase |
| FANCG | Stability |
| FANCE | Substrate recognition |
| FANCF | Complex assembly |
Recent research reveals connections between FANCL and PD:
The FA pathway intersects with neurodegeneration:
FANCL interacts with:
| Partner | Interaction Type | Functional Consequence |
|---|---|---|
| UBE2T | E2 enzyme | Ubiquitin transfer |
| FANCD2 | Substrate | Monoubiquitination |
| FANCI | Substrate | Monoubiquitination |
| FANCA | Complex | Scaffold |
| FANCM | Complex | DNA binding |
| FANCB | Complex | Stability |
| Parkin | Mitochondria | Mitophagy |
FANCL is a therapeutic target:
Potential neuroprotective strategies:
| Model | Phenotype | Key Findings |
|---|---|---|
| FANCL knockout mice | Embryonic lethal | Essential for development |
| Conditional KO | Bone marrow failure | ICL repair defect |
| Zebrafish | Developmental defects | Conserved function |
| Drosophila | DNA repair defects | Evolutionary conservation |