Lymphocyte-specific protein tyrosine kinase Adenovirus

Several protein tyrosine kinases have been identified within the Src gene family. On the basis of their associations with specific cell surface receptors, Src gene family members play critical roles in various signal transduction pathways. The highest levels of expression of the prototype member of this gene family, Src p60, are observed in platelets and in neuronal tissues. In contrast to Lck, which is expressed in T lymphocytes and natural killer cells, Lyn is expressed at highest levels in macrophages, platelets and B lymphocytes. Fyn is expressed in two different forms due to mutually exclusive splicing of alternative seventh exons. One form is expressed in the brain and the other in T lymphocytes. Yes p62 is broadly expressed in a wide range of cell types while c-Fgr p55 is preferentially expressed in cells of hematopoietic origin of the myeloid lineage. The Hck gene is expressed predominantly in cells of myeloid and B lymphocyte lineages. Blk is expressed in B lymphocytes, and Rak (also designated Frk in human, Gtk in rat and Bsk in mouse) is expressed in tissues of lymphoid, brain, breast, colon and bladder origin.