CATH Classification

Domain Context

CATH Clusters

Superfamily Classic Zinc Finger
Functional Family

Enzyme Information

2.3.2.27
RING-type E3 ubiquitin transferase.
based on mapping to UniProt O15344
S-ubiquitinyl-[E2 ubiquitin-conjugating enzyme]-L-cysteine + [acceptor protein]-L-lysine = [E2 ubiquitin-conjugating enzyme]-L-cysteine + N(6)- ubiquitinyl-[acceptor protein]-L-lysine.
-!- RING E3 ubiquitin transferases serve as mediators bringing the ubiquitin-charged E2 ubiquitin-conjugating enzyme (EC 2.3.2.23) and an acceptor protein together to enable the direct transfer of ubiquitin through the formation of an isopeptide bond between the C-terminal glycine residue of ubiquitin and the epsilon-amino group of an L-lysine residue of the acceptor protein. -!- Unlike EC 2.3.2.26 the RING-E3 domain does not form a catalytic thioester intermediate with ubiquitin. -!- Many members of the RING-type E3 ubiquitin transferase family are not able to bind a substrate directly, and form a complex with a cullin scaffold protein and a substrate recognition module (the complexes are named CRL for Cullin-RING-Ligase). -!- In these complexes, the RING-type E3 ubiquitin transferase provides an additional function, mediating the transfer of a NEDD8 protein from a dedicated E2 carrier to the cullin protein (see EC 2.3.2.32). -!- Cf. EC 2.3.2.31.

UniProtKB Entries (1)

O15344
TRI18_HUMAN
Homo sapiens
E3 ubiquitin-protein ligase Midline-1

PDB Structure

PDB 2JUN
External Links
Method SOLUTION NMR
Organism Escherichia
Primary Citation
Structure of the MID1 Tandem B-Boxes Reveals an Interaction Reminiscent of Intermolecular Ring Heterodimers
Tao, H., Simmons, B.N., Singireddy, S., Jakkidi, M., Short, K.M., Cox, T.C., Massiah, M.A.
Biochemistry