Ubiquitin is called so as:: (A) Present in all eukaryotic cells, (B) Takes pa in impoant reactions, (C) Is highly conserved, (D) None of the above
Answer is A. Ubiquitin, so named because it is present in all eukaryotic cells, is a small (8.5 kDa, 76 residues) polypeptide that targets many intracellular proteins for degradation. The primary structure of ubiquitin is highly conserved. Ref: Harper 28th edition, chapter 28.