A family of adaptor proteins downstream of (tyrosine) kinases consisting of five members, including Dok, Dok-R, DokL, Dok4, and Dok5, structurally rather similar to the insulin receptor substrate family of proteins. When tyrosine-phosphorylated they link clustered receptors to other signalling molecules including Nck, CrkL, Cas, and rasGTPase-activating protein (rasGAP). Dok, Dok-R, and DokL have all been shown to to play a negative role in receptor tyrosine kinase and cytokine signalling. DokR, also known as p56dok/FRIP, is involved in cytokine and immunoreceptor signalling in myeloid and T cells. Dok4 and Dok5 may be a separate subgroup and have been shown to potentiate signals emanating from the c-ret receptor.
Subjects: Medicine and Health.