Exists either covalently attached to another protein, or free (unanchored). When covalently bound, it is conjugated to target proteins via an isopeptide bond either as a monomer (monoubiquitin), a polymer linked via different Lys residues of the ubiquitin (polyubiquitin chains) or a linear polymer linked via the initiator Met of the ubiquitin (linear polyubiquitin chains). Polyubiquitin chains, when attached to a target protein, have different functions depending on the Lys residue of the ubiquitin that is linked: Lys-6-linked may be involved in DNA repair, Lys-11-linked is involved in ERAD (endoplasmic reticulum-associated degradation) and in cell-cycle regulation, Lys-29-linked is involved in proteotoxic stress response and cell cycle, Lys-33-linked is involved in kinase modification, Lys-48-linked is involved in protein degradation via the proteasome, Lys-63-linked is involved in endocytosis, DNA-damage responses as well as in signaling processes leading to activation of the transcription factor NF-kappa-B. Linear polymer chains formed via attachment by the initiator Met lead to cell signaling. Ubiquitin is usually conjugated to Lys residues of target proteins, however, in rare cases, conjugation to Cys or Ser residues has been observed. When polyubiquitin is free (unanchored-polyubiquitin), it also has distinct roles, such as in activation of protein kinases, and in signaling.
UBE1, also known as UBA1, belongs to the ubiquitin-activating E1 family. UBE1 gene complements an X-linked mouse temperature-sensitive defect in DNA synthesis, and thus may function in DNA repair. It is part of a gene cluster on chromosome Xp11.23. UBE1 catalyzes the first step in ubiquitin conjugation to mark cellular proteins for degradation. It also catalyzes the first step in ubiquitin conjugation to mark cellular proteins for degradation by first adenylating its C-terminal glycine residue with ATP, and thereafter linking this residue to the side chain of a cysteine residue in E1, yielding an ubiquitin-E1 thioester and free AMP. Defects in UBA1 can cause spinal muscular atrophy X-linked type 2 (SMAX2), also known as X-linked lethal infantile spinal muscular atrophy, distal X-linked arthrogryposis multiplex congenita or X-linked arthrogryposis type 1 (AMCX1). Spinal muscular atrophy refers to a group of neuromuscular disorders characterized by degeneration of the anterior horn cells of the spinal cord, leading to symmetrical muscle weakness and atrophy. SMAX2 is a lethal infantile form presenting with hypotonia, areflexia, and multiple congenital contractures.
Ubiquitin-Conjugating Enzyme E2 (UBE2A) is a member of the E2 Ubiquitin-Conjugating Enzyme family. The modification of proteins with ubiquitin is an important cellular mechanism for targeting abnormal or short-lived proteins for degradation. Ubiquitination involves at least three classes of enzymes: ubiquitin-activating enzymes; or E1s; ubiquitin-conjugating enzymes; or E2s; and ubiquitin-protein ligases; or E3s. UBE2A catalyzes the covalent attachment of ubiquitin to other proteins. UBE2A is required for postreplication repair of UV-damaged DNA. UBE2A Interacts with RAD18 and WAC.
Ubiquitin-conjugating enzyme E2 A (also known as HHR6A or UBE2A); encoded by human DNA repair genes HHR6A; belongs to the ubiquitin-conjugating enzymes (E2 enzymes) family and is likely to be involved in postreplication repair and induced mutagenesis. UBE2A is described as a CDK2 substrate. It is the human homologue of the product of the Saccharomyces cerevisiae RAD6 / UBC2 gene; a member of the family of ubiquitin-conjugating enzymes. In vivo; HHR6A phosphorylation peaks during the G2/M phase of cell cycle transition; with a concomitant increase in histone H2B ubiquitylation. Mutation of Ser120 to threonine or alanine abolished UBE2A activity; while mutation to aspartate to mimic phosphorylated serine increased UBE2A activity 3-fold. A mutation of UBE2A is consisdered as the cause of a novel X-linked mental retardation (XLMR) syndrome that affects three males in a two-generation family.
Ubiquitin-Conjugating Enzyme E2 B (UBE2B) belongs to the ubiquitin-conjugating enzyme family. UBE2B can catalyze the covalent attachment of ubiquitin to other proteins; and is essential for the multi-ubiquitination and degradation of N-end rule substrates. UBE2B is indispensability for postreplication repair of UV-damaged DNA and may be involved in neurite outgrowth.Additionally; UBE2B may have a role in sepsis-induced muscle protein proteolysis and cancer-induced cachexia.
Ubiquitin-Conjugating Enzyme E2 B (UBE2B) is a member of the ubiquitin-conjugating enzyme family. UBE2B accepts ubiquitin from the E1 complex and catalyzes its covalent attachment to other proteins. It is shown that UBE2B interacts with RAD18; UBR2; and WAC. UBE2B is required for post-replicative DNA damage repair. Additional; UBE2B plays a role in sepsis-induced muscle protein proteolysis and cancer-induced cachexia.
Ubiquitin-conjugating enzyme E2 D1（UBE2D1）belongs to the ubiquitin-conjugating enzyme family. Ubiquitination involves at least three classes of enzymes: ubiquitin-activating enzymes; or E1s; ubiquitin-conjugating enzymes; or E2s; and ubiquitin-protein ligases; or E3s. This enzyme is closely related to a stimulator of iron transport (SFT); and is up-regulated in hereditary hemochromatosis. It also functions in the ubiquitination of the tumor-suppressor protein p53 and the hypoxia-inducible transcription factor HIF1alpha by interacting with the E1 ubiquitin-activating enzyme and the E3 ubiquitin-protein ligases.
Ubiquitin-conjugating enzyme E2 D1 (UBE2D1); a member of human E2 ubiquitin-conjugating enzymes; is closely related to SFT; which is short for stimulator of iron (Fe) transport. In other words; UbcH5A is significantly up-regulated in the liver of iron-overloaded patients with hereditary hemochromatosis; as previously published for SFT. Moreover; a complex of UBE2D1 is critical in maintaining KRAS protein stability and propose that targeting such complex may be a unique strategy to degrade mutant KRAS to kill cancer cells.
Lascia la tua email e seleziona le aree che vuoi seguire per ricevere novita di prodotto, approfondimenti tecnici e promozioni piu pertinenti.
Puoi scegliere le macro-aree Life Science e Diagnostica oppure le singole specializzazioni.
Seleziona uno o piu ambiti di interesse per ricevere comunicazioni piu utili e mirate.
Aggiornamenti su ricerca, strumentazione e applicazioni per il mondo Life Science.
Novita, approfondimenti e promozioni per laboratori diagnostici e flussi operativi.
2025 TEMA Ricerca - All Rights Reserved.
