Members of the suppressor of cytokine signaling (SOCS) family of proteins contain C-terminal regions of homology called the SOCS box, which serves to couple SOCS proteins and their binding partners with the Elongin B and C complex. Several other families of proteins also contain SOCS boxes, but differ from the SOCS proteins in the type of domain they contain upstream of the SOCS box. The largest family of SOCS box-containing proteins is the ankyrin repeat and SOCS box-containing (ASB) protein family. Members of the ASB family include ASB-1 through ASB-18 and are involved in a variety of biological processes. ASB-17 is a 295 amino acid member of this family. ASB-17 contains one ankyrin repeat and one SOCS box domain. ASB-17 is thought to be a substrate-recognition subunit of a SCF-like ECS (Elongin-Cullin-SOCS-box protein) E3 ubiquitin protein ligase complex. This complex mediates the ubiquitination of target proteins and their subsequent proteasomal degradation.