POL2B Antibody

POLR2B Overview

POLR2B, also known as RPB2 or POL2RB, is the second-largest subunit of RNA polymerase II. It forms the catalytic core of Pol II alongside the largest subunit (POLR2A/RPB1) and is critical for transcriptional elongation and fidelity . Key functions include:

• Structural Role: Forms opposite sides of Pol II’s central cleft, enabling DNA unwinding and RNA synthesis .

• Catalytic Activity: Contributes to the polymerase’s enzymatic function, including proofreading .

• Cellular Localization: Exclusively nuclear, as confirmed by immunofluorescence studies .

Antibody Characteristics

POLR2B antibodies are primarily polyclonal, generated through immunization with recombinant proteins or synthetic peptides. Key features include:

Immunogen Design

• Active Motif’s Antibody: Targets a peptide within the N-terminal region (residues undisclosed) .

• Elabscience’s Antibody: Uses a recombinant fusion protein corresponding to residues in NP_000929.1 .

Research Applications

POLR2B antibodies are widely used in molecular biology and epigenetics:

Key Applications

• Chromatin Studies: Detecting POLR2B in nuclear extracts requires high-salt sonication protocols due to its chromatin-bound nature .

• Transcriptional Profiling: Mapping RNA polymerase II occupancy on DNA using ChIP-seq .

• Disease Research: Investigating POLR2B mutations linked to neurodevelopmental disorders .

Validation Data

• KO Controls: Knockout cell lines are critical for validating antibody specificity, as highlighted by studies showing ~20% of commercial antibodies fail target recognition .

• Multiplex Assays: Recombinant POLR2B antibodies outperform traditional monoclonals in Western blot and immunofluorescence .

Validation Gaps

• Epitope Specificity: Antibodies targeting the N-terminal region (e.g., Active Motif’s 61557) may miss truncation variants .

• Batch Variability: Polyclonal antibodies exhibit lot-to-lot variability, necessitating revalidation for critical assays .

Future Directions

Advancements in antibody engineering, such as recombinant phage display and automated screening systems, promise higher specificity and scalability . Coupling POLR2B antibodies with CRISPR-based transcriptional analysis could further elucidate its role in gene regulation.