Six cullin-like proteins, CULLIN1 (CUL1: At4g02570), CULLIN2 (further referred to here as CUL1b: At1g02980 to avoid confusion with human Cul2), CULLIN3a (CUL3a: At1g25830), CULLIN3b (CUL3b: At1g69670), CULLIN4 (CUL4: At5g46210), and ANAPHASE PROMOTING COMPLEX2 (APC2: At2g04660). They range in size from 85 to 98 kDa, and are all characterized by a conserved cullin-region ofaround 200 amino acids in