Component of a cullin-RING-based BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex that mediates the ubiquitination of target proteins, such as NPTXR, leading most often to their proteasomal degradation. Responsible for degradative ubiquitination of the WNK kinases WNK1, WNK3 and WNK4 (By similarity). Promotes growth of cell projections in oligodendrocyte precursors. Plays a role in the reorganization of the actin cytoskeleton. Component of a cullin-RING-based BCR (BTB-CUL3-RBX1) E3 ubiquitin-protein ligase complex. Interacts with NPTXR and CUL3. Interacts with KLHL12 (By similarity). Binds actin. Interacts (via N-terminus) with FYN (via SH3 domain). When over-expressed, colocalizes with NPTXR in perinuclear aggresomes (By similarity). A proportion colocalizes with the actin cytoskeleton. Detected in brain neurons, oligodendrocytes and astrocytes (at protein level).