ubq-1 Antibody
Description
Antibody Characteristics
The Ubi-1 clone (Product ID: ab7254) is a mouse monoclonal antibody targeting ubiquitin. Key specifications include:
This antibody detects free ubiquitin, mono-ubiquitinated proteins, and polyubiquitin chains, making it versatile for studying ubiquitination dynamics .
Protein Degradation Studies
Ubi-1 is employed to investigate ubiquitin-dependent proteolysis, including:
-
Neurodegenerative Diseases: Detection of ubiquitin-positive inclusions in Alzheimer’s disease (e.g., neurofibrillary tangles) and Parkinson’s disease (Lewy bodies) .
-
Cancer Research: Monitoring ubiquitin-conjugated proteins in tumor cells undergoing apoptosis or chemotherapy-induced stress .
Mechanistic Insights
-
DNA Repair: Ubiquitination regulates DNA damage response pathways, such as recruitment of BRCA1 and TP53BP1 to repair sites .
-
Immune Signaling: Ubiquitin modifications modulate innate immune responses, including NF-κB activation and interferon production .
Western Blot Performance
-
Detects ubiquitin at ≤3.12 ng in purified preparations and in MG132-treated cell lysates (enhanced ubiquitination under proteasomal inhibition) .
-
Recognizes both free ubiquitin (~8 kDa) and high-molecular-weight ubiquitinated proteins .
Immunofluorescence Localization
-
Stains cytoplasmic and nuclear ubiquitin aggregates in HeLa cells, NIH 3T3 fibroblasts, and neuronal models .
-
Used to validate ubiquitin accumulation in disease models, such as tauopathy in Alzheimer’s-like cellular systems .
Table 1: Ubiquitin Antibody Performance Comparison
| Antibody Clone | Specificity | Applications | Sensitivity (WB) | Key Citations |
|---|---|---|---|---|
| Ubi-1 | Pan-ubiquitin | WB, IF, IHC | ≤3.12 ng | 77+ |
| FK1 | Polyubiquitin (K48/K63) | WB, IHC, IP | ≤0.5 ng | 154+ |
| AUB01 | Free/polyubiquitin | WB, IF | ≤6.25 ng | 8+ |
Limitations and Considerations
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
Polyubiquitin chains, when attached to a target protein, have diverse functions depending on the lysine residue involved in the linkage: Lys-48-linked chains are primarily involved in protein degradation via the proteasome. Linear polymer chains, formed through attachment by the initiator methionine, are involved in cell signaling.
While ubiquitin typically conjugates to lysine residues on target proteins, conjugation to cysteine or serine residues has been observed in rare instances. Even when polyubiquitin is free (unanchored-polyubiquitin), it plays distinct roles, such as activating protein kinases and participating in signaling pathways.
