Essential component of the SCF (SKP1-CUL1-F-box protein) ubiquitin ligase complex, which mediates the ubiquitination of proteins involved in cell cycle progression, signal transduction and transcription (By similarity). In the SCF complex, serves as an adapter that links the F-box protein to CUL1 (By similarity). The functional specificity of the SCF complex depends on the F-box protein as substrate recognition component (By similarity). Its association with the holoenzyme telomerase ribonucleoprotein complex suggests that it may play a role in turnover of holoenzyme telomerase complex components (PubMed:17220281). Protein modification; protein ubiquitination. Component of multiple SCF (SKP1-CUL1-F-box) E3 ubiquitin-protein ligase complexes formed of CUL1, SKP1, RBX1 and a variable F-box domain-containing protein as substrate-specific subunit. Increased telomere length. Belongs to the SKP1 family.