Atrophin 1 (ATN1, dentatorubral–pallidoluysian atrophy protein, 1185 aa) is expressed in all tissues, but is proteolytically cleaved in neuronal cells and may be a transcriptional corepressor. The poly-Gln region of ATN1 is highly polymorphic (7–23 repeats) in the normal population and is expanded to about 49–75 repeats in dentatorubral–pallidoluysian atrophy. Atrophin-1-related protein (arginine–glutamic acid dipeptide repeats protein, 1566 aa) acts as a a transcriptional repressor during development and interacts with atrophin 1, the interaction being stronger if there are more repeats. There are a number of proteins that interact with atrophin including MAGI (ATN interacting protein 1) and E3 ubiquitin-protein ligase Itchy homologue ( ATN-interacting protein 4).
Subjects: Medicine and Health — Chemistry.