Substrate recognition component of a SCF (SKP1-CUL1-F-box protein) E3 ubiquitin-protein ligase complex which mediates the ubiquitination and subsequent proteasomal degradation of target proteins. Acts as a positive regulator of the BMP signaling pathway (By similarity). Required for dorsal/ventral pattern formation. Protein modification; protein ubiquitination. Part of the SCF (SKP1-CUL1-F-box) E3 ubiquitin-protein ligase complex SCF(FBXL15). Maternally expressed. At 24 hours post-fertilization (hpf), expressed mainly in head region. Belongs to the FBXL15 family.