Ubiquitin

Ubiquitin is a small regulatory protein found in most tissues of eukaryotic organisms, i. e. it occurs ubiquitously. It was discovered in 1975 by Gideon Goldstein and further characterized throughout the 1970s and 1980s. Four genes in the human genome code for ubiquitin: UBB, UBC, UBA52 and RPS27A.