Ubiquitin-protein ligases

A Ubiquitin-like Protein Unleashes Ubiquitin Ligases

Modification of cullin-RING ubiquitin ligases by the ubiquitin-like molecule Nedd8 promotes substrate ubiquitination. A crystal structure of a cullin modified by Nedd8 recently reported in Cell (Duda et al., 2008) and a biochemical study in Molecular Cell (Saha and Deshaies, 2008) reveal the dramatic impact on the ligase machinery by conjugation of ubiquitin or ubiquitin-like proteins.

Tag Team Ubiquitin Ligases

Cullin-RING (CRL) and RING1-IBR-RING2 (RBR) are two distinct types of ubiquitin ligases. In this issue, Scott et al. show that CRLs activate the RBR enzyme ARIH1 to initiate ubiquitin chains on CRL substrates, thereby marking an unexpected and important advance in our understanding of both enzymes.

Types of Ubiquitin Ligases

Ubiquitination is a post-translational modification of proteins involved in a variety of cellular processes. Ubiquitination requires the sequential action of three enzymes: E1 (ubiquitin-activating enzymes), E2 (ubiquitin-conjugating enzymes), and E3 (ubiquitin ligases). This SnapShot highlights the main types of E3 ubiquitin ligases, which can be classified in three families depending on the p...

Adenovirus E3 Ubiquitin Ligases

Mammalian HECT ubiquitin-protein ligases: biological and pathophysiological aspects.

Members of the HECT family of E3 ubiquitin-protein ligases are characterized by a C-terminal HECT domain that catalyzes the covalent attachment of ubiquitin to substrate proteins and by N-terminal extensions of variable length and domain architecture that determine the substrate spectrum of a respective HECT E3. Since their discovery in 1995, it has become clear that deregulation of distinct HE...