Function
Essential adapter component of E3 ubiquitin ligase complexes; involved in R7 photoreceptor cell differentiation, embryonic nervous system, external sensory organ development and specification of particular muscles. E3 ubiquitin ligase complexes mediate ubiquitination and subsequent proteasomal degradation of target proteins. Required for specification of R7 photoreceptor cell fate in the eye by participating in the ubiquitination and subsequent proteasomal degradation of Tramtrack (ttk), a general inhibitor of photoreceptor differentiation. Acts downstream of Notch signaling to specify the fate of the SOP (sensory organ precursor) cells and their progeny, probably via the sina-mediated proteasomal degradation of ttk. Its restricted pattern of expression, upon Notch and Ras signaling pathways, suggests that it acts as a key determinant in E3 complexes to trigger protein proteolysis in appropriate cells.
Sequence
MSTNQQQQANPSAAVAAPAASSEYLKRTCLICGCHTNQTINIYEPRSGPNIVQLIQAKFKFQPLNEDKFLCFSCNNWLINWHSLQAVNSNEAESQSQSPSHMGNSVLQQERTKLRPVAMVRPTVRVQPQSQPQLQPQVPINPTPAPIVYSKRRASRRSASVSRMSRVLRQCCVESLRRSPKKRNQQSVFVCLRPQGQKRSNAICKVECVAPRRKPVERLVKDVAATATPTPVLNTQSTPTYQRFPQPSVDGKVVAMFRRLGTTLSREEPAAYSAESNPACSKLPQIMSPLKEAPRWTRDLDDDEILLEFDTAISEVLPTARYQVTHEENKENQQAQEMELELEEEEEVDGRAELEVVQEAEAPLEPQSHHKQGNSHQNSHQASIQLAGLRLPMGLSISLV