BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex (KLHL20)

Function

• one of multiple E3 ubiquitin-protein ligase complexes formed of CUL3, RBX1 & variable BTB domain-containing proteins acting as both, adapter to cullin & substrate recognition
• the BCR complex may be active as a heterodimeric complex, in which NEDD8, covalently attached to one CUL3 molecule, binds to the C-terminus of a second CUL3 molecule
• mediates ubiquitination of
  • DAPK1, leading to its degradation by the proteasome, thus acting as a negative regulator of apoptosis
  • RHOA, leading to its degradation by the proteasome, thus regulating the actin cytoskeleton & cell migration

Structure

• subunits: CUL3, KLHL20, RBX1, KCTD13, KLHL42

Notes

• BCR complexes include:
  • BCR(SPOP) containing SPOP
  • BCR(KLHL9-KLHL13) complex with BTB domain proteins KLHL9 & KLHL13
  • the BCR(KLHL41) complex with BTB domain protein KLHL41
  • the BCR(KLHL42) complex with BTB domain protein KLHL42
  • BCR(KBTBD10) complex containing KBTBD10
  • BCR(ENC1) complex containing ENC1

More general terms

• molecular complex
• E3 ubiquitin ligase