Actin filament associated protein mediates c-Src related SRE/AP-1 transcriptional activation

AFAP is an adaptor protein involved in cytoskeletal organization and intracellular signaling. AFAP binds and activates c-Src; however, the downstream signals of this interaction remain unknown. Here we show that co-expression of AFAP and c-Src induce transcriptional activation of SRE and AP-1 in a c-Src activity dependent fashion. Structural-functional studies suggest that the proline-rich motif in the N-terminus of AFAP is critical for c-Src activation, and subsequent SRE/AP-1 transactivation and the actin-binding domain in the AFAP C-terminus is negatively involved in the regulation of AFAP/c-Src mediated SRE/AP-1 transactivation. Selective deletion of this domain enhances transactivation of SRE. We conclude that in addition to its role in the regulation of cytoskeletal structures, AFAP may also be involved in the c-Src related transcriptional activities.Structured summarySrcphysically interacts with AFAP by anti bait coimmunoprecipitation(View interaction)

Research highlights
► AFAP can bind c-Src via its proline-rich motif.
► AFAP binding can activate c-Src.
► AFAP/c-Src interaction leads to SRE and AP-1 transactivation.
► Actin binding domain of AFAP negatively regulates SRE/AP-1 transactivation.