Josephin Domain Containing Protein 1 (JOSD1)

JOSD1, Contains 1 Josephin domain. Josephin domain-containing proteins from a variety of species are active de-ubiquitination enzymes. The neurodegenerative disease spinocerebellar ataxia type 3 (SCA3) is caused by the presence of an extended polyglutamine stretch (polyQ) in the unstructured C-terminus of the human ataxin-3 (AT3) protein. The structured N-terminal Josephin domain (JD) of AT3 is conserved within a novel family of potential ubiquitin proteases, the JD-containing proteins, which are sub-divided into two groups termed ataxins and Josephins. These AT3 orthologs are encoded by the genomes of organisms ranging from Plasmodium falciparum to humans, with most species possessing more than one homolog. While Josephins consist of JDs alone, ataxins contain additional functional domains that may influence their enzyme activity.