Tyrosine kinase non-receptor 1 (TNK1) is related to the Ack1 (TNK2) non-receptor kinase that binds cdc42 and inhibits GTPase activity of this cell cycle regulator. TNK1 is broadly expressed in embryogenic tissues and leukemia cell lines, but is restricted to select adult tissues. TNK1 is a putative 72 kDa protein comprised of an N-terminal kinase domain, a central SH3 domain and a proline-rich tail. Interaction with PLCγ in vitro indicates a possible role in phospholipid signal transduction pathways. Though the exact mechanism is currently unclear, active TNK1 may play a role in regulating cell death by preventing TNF-α-induced NF-κB transactivation. |