FBXW5 is a F-box protein and a DDB1-binding WD40 (DWD) protein that serves as a substrate recognition component of both SCF (SKP1-CUL1-F-box protein) and DCX (DDB1-CUL4-X-box) E3 ubiquitin-protein ligase complexes [, ]. It has also been shown to negatively regulate TAK1 MAP3K in the IL-1beta signaling pathway []. Interestingly, FBXW5 binds centriolar protein HsSAS-6 and promotes its ubiquitylation; this way FBXW5 can restrict centrosome re-duplication through degradation of HsSAS-6 [].
