Overview:

Ubiquitin is a highly-conserved protein that is widely expressed in eukaryotes (1). Ubiquitin is required for the rapid proteasomal degradation of intracellular proteins in an ATP-dependent manner. UBB+1 is a frameshift mutant form of ubiquitin, which not only inhibits the function of the proteasome machinery, but also accumulates in the cells associated with tauopathies, including Alzheimer's disease and polyglutamine diseases because of the cell’s inability to clear cytotoxic misfolded amyloid-beta and phosphorylated-tau (2). UBB+1 also serves as an endogenous marker for proteasomal dysfunction in liver disease and muscle disease, where the protein may also have a role in pathogenesis.

Gene Aliases:

UBB, MGC8385, FLJ25987

Genbank Number:

NM_018955

References:

1. Baker, R T. et al: The human ubiquitin gene family: structure of a gene and pseudogenes from the Ub B subfamily. Nucleic Acids Res.15: 443-463, 1987.

2. Fratta, P. et al: Mutant ubiquitin UBB+1 is accumulated in sporadic inclusion-body myositis muscle fibers. Neurology. 2004 Sep 28;63(6):1114-7.