DOK proteins are enzymatically inert adaptor or scaffolding proteins. They provide a docking platform for the assembly of multimolecular signaling complexes. Plays a role as negative regulator of the mobilization of calcium ions and of calcium signaling. Homooligomer. Interacts with GRB2 and INPP5D/SHIP. PTB domain mediates receptor interaction. Tyrosine-phosphorylated in the presence of GRB2. Belongs to the DOK family. Type A subfamily.