Ubiquitin-dependent degradation of active Src.

Signaling by members of the Src family of protein tyrosine kinases, such as Src and Fyn, is important in many biological responses, including gene transcription, cell-cycle progression, and cell adhesion and spreading [1] [2]. Unregulated Src kinase activity has been implicated in the progression of colon cancer and transformation of cultured cells [3] [4] [5] [6]. Thus, precise regulation of Src activity is critical for normal cell growth.