Ubiquilins contain a N-terminal ubiquitin-like domain and a C-terminal ubiquitin-associated domain. They physically associate with both proteasomes and ubiquitin ligases, and thus are thought to functionally link the ubiquitination machinery to the proteasome to effect in vivo protein degradation.
Possible Role In Preventing Alzheimers Disease
Ubiquilin has also been shown to modulate accumulation of presenilin proteins, and is found in lesions associated with Alzheimer's and Parkinson's disease. Two transcript variants encoding different isoforms have been found for this gene.
Higher levels of ubiquilin-1 in the brain decreased malformation of the APP molecule which plays a key role in triggering Alzheimers disease. Conversely, lower levels of ubiquilin-1 in the brain were associated with increased malformation of APP.
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