Engelsk definition
Protein domains of approximately 120 amino acids that form two perpendicular anti-parallel beta sheets connected by a loop of variable length and a C-terminal amphipathic helix. PH domains occur in many INTRACELLULAR SIGNALING PROTEINS and CYTOSKELETAL PROTEINS where they bind PHOSPHATIDYLINOSITOLS within the CELL MEMBRANE and INTRACELLULAR MEMBRANES, as well as proteins that include the Betagamma-subunits of HETEROTRIMERIC GTP-BINDING PROTEINS, and PROTEIN KINASE C. These interactions allow the targeting of proteins to different cellular compartments and SIGNAL TRANSDUCTION PATHWAYS.