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 involved in cell cycle progression, signal transduction and transcription (By similarity). Specifically recognizes phosphorylated CDKN1B/p27kip and is involved in regulation of G1/S transition (PubMed:10790373). Degradation of CDKN1B/p27kip also requires CKS1. Recognizes target proteins ORC1, CDT1, RBL2, KMT2A/MLL1, CDK9, RAG2, FOXO1, UBP43, YTHDF2, and probably MYC, TOB1 and TAL1. Degradation of TAL1 also requires STUB1. Recognizes CDKN1A in association with CCNE1 or CCNE2 and CDK2. Promotes ubiquitination and destruction of CDH1 in a CK1-dependent manner, thereby regulating cell migration (By similarity). Through the ubiquitin-mediated proteasomal degradation of viral proteins may have an antiviral activity. Protein modification; protein ubiquitination. Part of a SCF(SKP2) complex consisting of CUL1, RBX1, SKP1 and SKP2. Component of a SCF(SKP2)-like complex containing CUL1, SKP1, TRIM21 and SKP2. Interacts directly with CUL1 and SKP1. Interacts with ASB2 which is the substrate-recognition component of a probable ECS E3 ubiquitin-protein ligase complex; ASB2 is likely to bridge the formation of dimeric E3-ubiquitin-protein ligase complexes composed of an ECS complex and an SCF(SKP2) complex. Interacts with CKS1. Interacts with the cyclin-A-CDK2 complex. Interacts with ORC1, phosphorylated CDT1, phosphorylated RBL2, ELF4, phosphorylated RAG2, FOXO1, UBP43, MYC, TOB1, TAL1 and KMT2A/MLL1. Interacts with TRIM21 (By similarity). Interacts with cyclin-E (PubMed:10790373). Interacts with CARM1 (PubMed:30366907). Ubiquitinated by the APC/C complex, leading to its degradation by the proteasome. Deubiquitinated by USP13 (By similarity). Acetylation at Lys-68 and Lys-71 increases stability through impairment of APC/C-mediated proteolysis and promotes cytoplasmic retention. Deacetylated by SIRT3 (By similarity).