Protein | E3 components | Structures solved* | Key recognition fold on adaptor | Key determinants on cullin NTD | ||
---|---|---|---|---|---|---|
 | Adaptor | Substrate recognition | RING |  |  |  |
CUL1 | Skp1 | F-box protein | ROC1/Rbx1 | Skp1/BTB/POZ fold in Skp1 [6] | CUL1 H2 and H5 helices [6] | |
CUL2 | EloC/EloB | VHL | ROC1/Rbx1 | No CUL2 structure; VHL-EloC-EloB [60] | CUL2 H2 and H5 helices [14] | |
CUL3 | BTB (adaptor-targeting) | BTB (adaptor-targeting) | ROC1/Rbx1 | SPOP BTB-SBC [13] | CUL3 H2 and H5 helices [62] | |
CUL4A | DDB1 | DCAF | ROC1/Rbx1 | BPB in DDB1 [9] | CUL4A H2 and H5 helices [9]; CUL4A amino-terminal extension [9] | |
CUL4B | DDB1 | DCAF | ROC1/Rbx1 | Not available | BPB in DDB1 (predicted) | CUL4B H2/H5 (predicted) |
CUL5 | EloC/EloB | SOCS protein | ROC2/Rbx2 | CUL5CTD-Rbx1 [37]; SOCS2- EloC-EloB [63]; HIV Vif-EloC-EloB [16] | CUL5 H2 and H5 helices [64]; CUL5 loop 2 (amino acids 51 to 60) [16]; CUL5 loop 5 (amino acids 118 to 134) [16] | |
CUL7 | Skp1 | Fbw8 | ROC1/Rbx1 | CUL7 CPH-p53 TD [65] | Skp1/BTB/POZ fold in Skp1 (predicted) | Unknown |
PARC | Unknown | Unknown | Unknown | Not available | Unknown | Unknown |