Its most well known function occurs when a chain of at least four of these molecules attaches to a target, which directs target proteins to the proteasome.
In eukaryotes, the genes that encode this protein are arranged in tandem repeats, and this protein is thought to regulate gene transcription by binding to histone H2A. The attachment of this protein to its target is mediated by a hierarchical three enzyme cascade that starts with an E1 activating protein and ends with a substrate specific E3 ligase. This protein uses a glycine residue to bind to a lysine residue on the target protein and can tag a transmembrane protein for removal from a membrane or bind to cyclin to regulate cell division. Its most well known function occurs when a chain of at least four of these molecules attaches to a target, which directs target proteins to the proteasome. For 10 points, name this abundant protein that is used to target other proteins for degradation.
In eukaryotes, the genes that encode this protein are arranged in tandem repeats, and this protein is thought to regulate gene transcription by binding to histone H2A. The attachment of this protein to its target is mediated by a hierarchical three enzyme cascade that starts with an E1 activating protein and ends with a substrate specific E3 ligase.
{Ubiquitin}