USP45 Antibody

Introduction to USP45 Antibody

USP45 antibody is a polyclonal or monoclonal reagent designed to detect ubiquitin-specific peptidase 45 (USP45), a deubiquitinating enzyme (DUB) involved in DNA repair, tumorigenesis, and cell migration. USP45 regulates protein stability by removing ubiquitin chains from substrates like ERCC1 and Spindly, influencing DNA damage response pathways and oncogenic processes . Antibodies targeting USP45 are validated for applications including Western blotting (WB), immunohistochemistry (IHC), ELISA, and immunofluorescence (IF) .

Key Applications in Research

Validation and Specificity Data

USP45 antibodies are rigorously validated across species and experimental conditions:

Reactivity and Host Information

• Host Species: Rabbit (polyclonal) or Mouse (monoclonal) .

• Cross-Reactivity: Confirmed in human, mouse, and rat samples .

Validation Examples

• WB: Detected endogenous USP45 in SGC-7901 gastric cancer cells .

• IHC: Stained USP45 in human stomach cancer tissues with TE buffer antigen retrieval .

Role in DNA Repair and Cancer

• ERCC1 Interaction: USP45 deubiquitinates ERCC1, enabling its recruitment to UV-induced DNA damage sites. Cells lacking USP45 show defective repair of cyclobutane pyrimidine dimers (CPDs) .

• Oncogenic Potential:

  • USP45 is upregulated in CHOL, COAD, LIHC, and STAD, correlating with poor patient survival .

  • Associates with immune checkpoint molecules (e.g., PD-L1) and tumor stemness markers .

Interaction with Spindly

• USP45 forms a complex with Spindly, a protein involved in cell migration. Their interaction depends on USP45’s catalytic activity, and USP45 removes K48-linked ubiquitin chains from Spindly .

• USP45 knockout reduces cell migration, mimicking Spindly-deficient phenotypes .

Technical Considerations and Limitations

• Antigen Retrieval: Required for IHC (e.g., TE buffer pH 9.0) .

• Cross-Reactivity: Potential false positives in tissues with high USP45 homolog expression .

• Catalytic Dependency: USP45’s interaction with substrates like Spindly requires active deubiquitinase activity .

Future Directions

USP45 antibodies will remain pivotal for:

1. Mechanistic Studies: Elucidating USP45’s role in immune evasion and metastasis .

2. Therapeutic Development: Targeting USP45 in cancers with ERCC1–XPF dysregulation .

3. Biomarker Validation: Correlating USP45 expression levels with chemotherapy resistance .