Figure 4
![(A) The structures of the RING1 domain from parkin (PDB code 4I1F [35]; orange) is superimposed with the RING domain from c-Cbl (PDB code 1FBV [5]; grey). The superposition was done using the Cα positions of the eight Zn2+-co-ordinating residues in each protein. The two regions (L1 and L2) in each protein and residues in parkin expected to be key for E2 interaction are indicated. (B) Sequence comparison for the RING1 domains of the RBR proteins parkin, HHARI and HOIP with representative RING E3 ligases c-Cbl, TRAF6 and cIAP2 showing important residues for E2 recruitment in L1 and L2 loops (red dot).](https://port.silverchair-cdn.com/port/content_public/journal/biochemj/458/3/10.1042_bj20140006/2/bj4580421fig4.jpeg?Expires=1716507224&Signature=hFRxL8rRGknXzWIHybs6Ul-XvXvZa5NpJvkL2PQUMuW79~QUbqIKpjEpXrXLVddLqw-05RgaxR8082eKWiONnsfWxV6sFhT8Q8SqISdI-lnB4X8ilTg7Ltthw4EsNPt8NgHIUNgI1jaqrSk3QMLuAtDJcOXQVV0Ud~AS19P5KXY0Gt~2P7iRny33nWSQoSEozRBddOQD4vbkKp0zZRJuocllaXGJ8s1vbs7ofB-Wu-HibrXFwys-kE2IZmWykCSA-P9lMudeckiBu8nFwsomcTO~KB3-PLSAlLpBsRbXq8xMDo9dNbexhQjtEIE-3JmuOj8z0mON0ERLhqciEhjhFQ__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Comparison of RING domain structures for RBR and canonical RING E3 ubiquitin ligases
(A) The structures of the RING1 domain from parkin (PDB code 4I1F [35]; orange) is superimposed with the RING domain from c-Cbl (PDB code 1FBV [5]; grey). The superposition was done using the Cα positions of the eight Zn2+-co-ordinating residues in each protein. The two regions (L1 and L2) in each protein and residues in parkin expected to be key for E2 interaction are indicated. (B) Sequence comparison for the RING1 domains of the RBR proteins parkin, HHARI and HOIP with representative RING E3 ligases c-Cbl, TRAF6 and cIAP2 showing important residues for E2 recruitment in L1 and L2 loops (red dot).
