The E3 ubiquitin ligases are classified into three major types: the really interesting new gene (RING), the homologous to the E6-AP carboxyl terminus (HECT) and the RING-between-RING (RBR) types of E3 ligases.
RING E3s are characterized by the presence of a zinc-binding domain called RING or by a U-box domain. Some RING E3s are composed by multiple subunits, such as the cullin-RING ligases (CRLs) and the anaphase-promoting complex/cyclosome (APC/C).
The conserved HECT domain is characterized by a bi-lobar architecture: the N-terminal lobe and the C-terminal lobe. The two lobes are tethered by a flexible hinge region. Based on the N-terminal extensions, human HECTs can be classified into three subfamilies: (1) Nedd4 family, which contains tryptophan-tryptophan (WW) motifs, (2) HERC (HECT and RCC1-like domain) family, which possesses one or more regulators of chromosome condensation 1 (RCC1)-like domains (RLDs), and (3) “other” HECTs that contain various domains.
The RBR name derives from the presence of two predicted RING domains (RING1 and RING2), which separates by an in-between-RING domain (IBR). The IBR domain adopts the same fold as the RING2 (or Rcat) domain while lacking the catalytic cysteine residue; therefore, it has been also called a BRcat (benign-catalytic) domain.
Based on the particular structural characteristics, some E3 ligases contains significant amount of non-secondary structure featuring random coil, some are poorly expressed, making them unamendable for further characterizations. Profacgen offers a comprehensive protein expression service to produce E3 ligases or target proteins from many different host systems for research, functional assays, target validation, or antibody development.
Bioinformatics analysis – molecular characterization analysis.
Cloning - desired DNA into an expression vector with selected features.
Protein expression - expression construct in suitable expression system.
Protein purification - via affinity chromatography, size exclusion chromatography and HPLC, etc.
Further options - tag removal, endotoxin removal, post-translational modifications...
Profacgen provides quality ubiquitination services with the following advantages:
(1) Customize protein synthesis.
(2) High production and recovery rate.
(3) Scale-up protein production.
(4) Timely feedback on project progress.
Profacgen aims to provide customers timely and effective scientific research, please contact us for individual services.
1. Morreale FE, Walden H. (2016). Types of Ubiquitin Ligases. Cell, 165(1), 248–248.e1. doi:10.1016/j.cell.2016.03.003
2. Shen Q, Qiu Z, Wu W, Zheng J, Jia Z. (2018). Characterization of interaction and ubiquitination of phosphoenolpyruvate carboxykinase by E3 ligase UBR5. Biology Open, 7(12), bio037366. doi:10.1242/bio.037366
3. Lin H, Li S, Shu HB. (2019). The Membrane-Associated MARCH E3 Ligase Family: Emerging Roles in Immune Regulation. Frontiers in Immunology, 10. doi:10.3389/fimmu.2019.01751