FYVE domain

FYVE zinc finger domain is named after the four cysteine-rich proteins: Fab 1 (yeast orthologue of PIKfyve), YOTB, Vac 1 (vesicle transport protein), and EEA1, in which it has been found.

The FYVE finger binds two zinc ions. The FYVE finger has eight potential zinc coordinating cysteine positions and is characterized by having basic amino acids around the cysteines. Many members of this family also include two histidines in a motif R+HHC+XCG, where + represents a charged residue and X any residue.

FYVE domains bind Phosphatidylinositol 3-phosphate, in a way dependent on its metal ion coordination and basic amino acids. It has been speculated these bindings cause conformational changes or regulate protein-protein or lipid-protein interactions.

The FYVE finger is structurally similar to the RING domain and the PHD finger.

The FYVE domain has been connected to vacuolar protein sorting and endosome function.

Examples
The following is a list of human proteins containing this domain:
 * ANKFY1
 * EEA1
 * FGD1;     FGD2;      FGD3;      FGD4;      FGD5;      FGD6
 * FYCO1
 * HGS
 * MTMR3;    MTMR4
 * PIKFYVE;   PLEKHF1;   PLEKHF2
 * RUFY1; RUFY2
 * WDF3;     WDFY1;     WDFY2;     WDFY3
 * ZFYVE1;   ZFYVE16;   ZFYVE19; ZFYVE20;   ZFYVE21;   ZFYVE26;   ZFYVE27;   ZFYVE28;   ZFYVE9