Probable substrate-recognition component of a SCF-like ECS (Elongin-Cullin-SOCS-box protein) E3 ligase complex which mediates the ubiquitination and subsequent proteasomal degradation of target proteins (By similarity). Mediates Notch-induced ubiquitination and degradation of TCF3/E2A and JAK2 (By similarity). May play a role in testis development (PubMed:11509662). Protein modification; protein ubiquitination. Interacts with CUL5 and RNF7. Highest expression in testis, spleen, bone marrow and salivary gland. The SOCS box domain mediates the interaction with the Elongin BC complex, an adapter module in different E3 ubiquitin-protein ligase complexes. Decreased spermatogenesis with less complete filling of seminiferous tubules but fertility does not appear to be affected. Belongs to the ankyrin SOCS box (ASB) family.