FANCI


Fanconi anemia, complementation group I also known as KIAA1794, is a protein which in humans is encoded by the FANCI gene. Mutations in the FANCI gene are known to cause Fanconi anemia.

Function

The Fanconi anemia complementation group currently includes FANCA, FANCB, FANCC, FANCD1, FANCD2, FANCE, FANCF, FANCG, FANCI, FANCJ, FANCL, FANCM and FANCN. The previously defined group FANCH is the same as FANCA. Fanconi anemia is a genetically heterogeneous recessive disorder characterized by cytogenetic instability, hypersensitivity to DNA crosslinking agents, increased chromosomal breakage, and defective DNA repair. The members of the Fanconi anemia complementation group do not share sequence similarity; they are related by their assembly into a common nuclear protein complex. This gene encodes the protein for complementation group I. Alternative splicing results in two transcript variants encoding different isoforms.
FANCI forms a heterodimer with FANCD2 protein. Both FANCD2 and FANCI are monoubiquitinated by the Fanconi anemia core complex subunit FANCL. FANCI monoubiquitination is essential for repairing DNA interstrand crosslinks, and clamps the protein on DNA together with its partner protein FANCD2. The monoubiquitinated FANCD2:FANCI complex coats DNA in a filament-like array, potentially as a way to protect DNA associated with stalled replication.