Ankyrin Repeat And SOCS Box Containing Protein 4 (ASB4)

ASB4 is a member of the ankyrin repeat and SOCS box-containing (ASB) family of proteins. They contain ankyrin repeat sequence and SOCS box domain. The SOCS box serves to couple suppressor of cytokine signalling (SOCS) proteins and their binding partners with the elongin B and C complex, possibly targeting them for degradation. Multiple alternatively spliced transcript variants have been described for this gene but some of the full length sequences are not known. Sequence analysis predicted that the 426-amino acid protein, which is 93% identical to the mouse protein, contains 9 ankyrin repeats and a C-terminal SOCS box. Northern blot analysis of mouse tissues revealed expression of a 3.0-kb transcript restricted to testis. Genomic sequence analysis determined that the ASB4 gene contains 5 exons spanning 51 kb.