Docking Protein 3 (DOK3)

The deduced 444-amino acid mouse protein contains an N-terminal PH domain, a central PTB domain, and a proline-rich C-terminal domain. Dokl is relatively serine/threonine-rich overall and contains several potential phosphorylation sites for ser/thr protein kinases. Dokl shares 60% and 57% sequence similarity with p62dok (DOK1) over the PH and PTB domains, respectively, with lower similarity over the C-terminal regions. Northern blot analysis of mouse tissues detected several species with high expression in spleen and lung and low levels in other tissues. RNAse protection studies detected very high Dokl expression in bone marrow and spleen, low expression in thymus, and no expression in NIH3T3 cells. Immunofluorescence studies localized Dokl to the cytoplasm in NIH3T3 cells.