View in Gene3D

CATH Superfamily 2.20.25.20

The name of this superfamily has been modified since the most recent official CATH+ release (v4_4_0). At the point of the last release, this superfamily was: waiting to be named.

Functional Families

Overview of the Structural Clusters (SC) and Functional Families within this CATH Superfamily. Clusters with a representative structure are represented by a filled circle.
« Back to all FunFams

FunFam 4: RBR-type E3 ubiquitin transferase

There are 1 EC terms in this cluster

Please note: EC annotations are assigned to the full protein sequence rather than individual protein domains. Since a given protein can contain multiple domains, it is possible that some of the annotations below come from additional domains that occur in the same protein, but have been classified elsewhere in CATH.

Note: The search results have been sorted with the annotations that are found most frequently at the top of the list. The results can be filtered by typing text into the search box at the top of the table.

EC Term Annotations Evidence
RBR-type E3 ubiquitin transferase. [EC: 2.3.2.31]
[E2 ubiquitin-conjugating enzyme]-S-ubiquitinyl-L-cysteine + [acceptor protein]-L-lysine = [E2 ubiquitin-conjugating enzyme]-L-cysteine + [acceptor protein]-N(6)-ubiquitinyl-L-lysine.
  • RBR-type E3 ubiquitin transferases have two RING fingers separated by an internal motif (IBR, for In Between RING).
  • The enzyme interacts with the CRL (Cullin-RING ubiquitin Ligase) complexes formed by certain RING-type E3 ubiquitin transferase (see EC 2.3.2.27), which include a neddylated cullin scaffold protein and a substrate recognition module.
  • The RING1 domain binds an EC 2.3.2.23, and transfers the ubiquitin that is bound to it to an internal cysteine residue in the RING2 domain, followed by the transfer of the ubiquitin from RING2 to the substrate.
  • Once the substrate has been ubiquitinated by the RBR-type ligase, it can be ubiqutylated further using ubiquitin carried directly on E2 enzymes, in a reaction catalyzed by EC 2.3.2.27.
  • Activity of the RBR-type enzyme is dependent on neddylation of the cullin protein in the CRL complex.
  • Cf. EC 2.3.2.26, EC 2.3.2.27, and EC 2.3.2.32.
 3 A2A7Q9 Q1L8L6 Q6ZMZ0
CATH-Gene3D is a Global Biodata Core Resource Learn more...