Ubiquitin is an abundant and essential cellular 9-kd protein that is conserved across evolution from yeast to humans. Ubiquitin is used by cells as a covalent modifier of other proteins both to activate their function and to target them for degradation, depending on the degree of ubiquitination.
Ubiquitin is a small, highly conserved protein which plays an important role in protein breakdown, covalently bonding to proteins to mark them for proteolytic degradation in a process called ubiquitination. Ubiquitin also binds to inclusion bodies (accumulations of protein) in pathological conditions such as Parkinson’s and Alzheimer's disease.
E3 ubiquitin ligases are standards in most antibody catalogs. These proteins are essential to the process of ubiquitination, which is expressed in protein pathways throughout the body and is often linked to disease states. It is widely used as a biomarker, with ubiquitin antibodies being widely used to identify the protein accumulations (inclusion bodies) which occur in conditions such as Alzheimer’s, Parkinson’s and Huntington's disease.