Substrate-specific adapter of a BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex that mediates ubiquitination of Ras (K-Ras/KRAS, N-Ras/NRAS and H-Ras/HRAS). Is a negative regulator of RAS-MAPK signaling that acts by controlling Ras levels and decreasing Ras association with membranes. Protein modification; protein ubiquitination. Homodimer. Component of the BCR(LZTR1) E3 ubiquitin ligase complex, at least composed of CUL3, LZTR1 and RBX1. Interacts with Ras (K-Ras/KRAS, N-Ras/NRAS and H-Ras/HRAS). Interacts with RAF1. Interacts with SHOC2. Interacts with PPP1CB. Phosphorylated on tyrosine upon induction of apoptosis, leading to its degradation by the proteasome. Belongs to the LZTR1 family.