Anti-phospho-Ubiquitin (Ser57)

Ubiquitin (Ub) is initially produced as a 229 amino acids Polyubiquitin-B (UniProt: P0CG47) precursor protein encoded by the UBB gene (Gene ID: 7314) or a 685 amino acids Polyubiquitin-C precursor protein (UniProt: P0CG48) encoded by the UBC gene (Gene ID: 7316) in human. Ub 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). Ub is linked covalently via its carboxyl terminus (Gly76) to usually Lys residues in target proteins. In a given target Lys residue can be linked to one single Ub molecule (monoubiquitylated) or to a chain of Ub molecules (polyubiquitylated). In a polyUb chain, Ub molecules can be linked through one of the seven Lys residues (K6, K11, K27, K29, K33, K48, and K63) or through the Ub N-terminus Met1 residue (which generates linear chains). Polyubiquitin chains, when attached to a target protein, have different functions depending on the Lys residue of the ubiquitin that is linked. For example, lysine 6-linked may be involved in DNA repair; lysine 11-linked is involved in endoplasmic reticulum-associated degradation (ERAD) and in cell-cycle regulation, and lysine 29-linked is involved in lysosomal degradation. Lysine 48-linked chains mark proteins for proteasomal degradation, while lysine 63-linked chains are involved in endocytosis, DNA-damage responses, and in signaling leading to activation of the transcription factor NF-kappa-B. Ubiquitin undergoes phosphorylation at the serine 57 by a ubiquitin kinase and this phosphorylation is an important modifier of ubiquitin function, particularly in response to proteotoxic stress. This phosphorylation may also be a deciding factor whether ubiquitin is recycled or degraded during multi-vesicular body sorting on endosomes. (Ref.: Hepowit, NL., et al (2020). eLife 9; e58155; Lee, S., et al. (2017) eLife. 6; e29176).

KLH-conjugated linear peptide corresponding to 10 amino acids surrounding phosphoserine 57 of human Ubiquitin.

Quality Control Testing

Evaluated by Western Blotting with a construct containing GST-tagged recombinant fragment of Ubiquitin phosphorylated on serine 57.

Western Blotting Analysis (WB): A 1:1,000 dilution of this antibody detected a construct containing GST-tagged recombinant Ubiquitin phosphorylated on serine 57, but did not react with non-phosphorylated construct.

Tested Applications

Affinity Binding Assay: A representative lot of this antibody bound phospho-Ubiquitin (ser57) peptide with a KD of 1.0 x 10-12 in an affinity binding assay.

Note: Actual optimal working dilutions must be determined by end user as specimens, and experimental conditions may vary with the end user

Anti-phospho-Ubiquitin (Ser57), Cat. No. ABS2206, is a rabbit polyclonal antibody that detects phospho-Ubiquitin (Ser57) and is tested for use in Affinity Binding Assay and Western Blotting.

This rabbit polyclonal antibody specifically detects Ubiquitin phosphorylated on serine 57.

Purified rabbit polyclonal antibody in buffer containing 0.1 M Tris-Glycine (pH 7.4), 150 mM NaCl with 0.05% sodium azide.

Recommend storage at +2°C to +8°C. For long term storage antibodies can be kept at -20°C. Avoid repeated freeze-thaws.

Concentration: Please refer to the Certificate of Analysis for the lot-specific concentration.

Unless otherwise stated in our catalog or other company documentation accompanying the product(s), our products are intended for research use only and are not to be used for any other purpose, which includes but is not limited to, unauthorized commercial uses, in vitro diagnostic uses, ex vivo or in vivo therapeutic uses or any type of consumption or application to humans or animals.