Involved in ubiquitination and subsequent proteasomal degradation of target proteins. Together with CUL1, RBX1 and a F-box protein, it forms a SCF E3 ubiquitin ligase complex. The functional specificity of this complex depends on the type of F-box protein. In the SCF complex, it serves as an adapter that links the F-box protein to CUL1. SCF(UFO) is required for vegetative and floral organ development as well as for male gametogenesis. SCF(TIR1) is involved in auxin signaling pathway. SCF(COI1) regulates responses to jasmonates. SCF(EID1) and SCF(AFR) are implicated in phytochrome A light signaling. SCF(ADO1), SCF(ADO2), SCF(ADO3) are related to the circadian clock. SCF(ORE9) seems to be involved in senescence. SCF(EBF1/EBF2) may regulate ethylene signaling. Plays a role during embryogenesis and early postembryonic development, especially during cell elongation and division. Contributes to the correct chromosome segregation during tetrad formation. Protein modification; protein ubiquitination. Part of a SCF E3 ubiquitin ligase complex composed of SKP1, CUL1, RBX1 (RBX1A or RBX1B) and F-box proteins. Interacts with SKIP1, SKIP2, SKIP3, SKIP4, SKIP6, FIB1/SKIP7, PP2A13/SKIP9, SKIP11, PP2B11/SKIP12, PP2A14/SKIP13, SKIP14, SKIP15/FBX3, SKIP16, SKIP17, FBW2/SKIP18, SKIP19/FBL20, SKIP20, PP2B1/SKIP21, SKIP22, SKIP24, SKIP27, SKIP31, SKIP32, SKIP34, ADO1/ZTL, ADO2/LKP2, ADO3/FKF1, AFR, COI1, EBF1, EBF2, EID1, ORE9, PP2A13, PP2B10, TIR1, UFO, SKP2A, CPR1/CPR30, NUP58, At1g55000, At1g67340, At1g78100, At3g04660, At3g61590, At4g38940 and At5g49610. The SKP1B subunit of the SCF E3 ubiquitin ligase complex can probably interact directly with KIN10, KIN11 and the proteasome subunit PAD1. Interacts with SNL1. In case of polerovirus infection, part of a SCF P0 complex composed of the viral silencing suppressor P0, SKP1, and CUL1. Interacts with turnip yellows virus P0. Expressed in tips, cortical layer and epidermis of roots. Detected in whole seedling, vascular tissues, pith and vascular bundle of young stem, leaves, inflorescence meristem, young floral buds and organ primordia, flowers, developing seeds and through the valve of siliques. Expressed in male meiocytes, pollen, embryo and endosperm. Expressed during all stages of embryogenesis. Belongs to the SKP1 family. Extended N-terminus.