RPL12B Antibody

What is RPL12 and what is its function in cellular systems?

RPL12 is a component of the 60S large ribosomal subunit belonging to the L11P family of ribosomal proteins. Located primarily in the cytoplasm, RPL12 binds directly to 26S ribosomal RNA and plays a critical role in protein synthesis as part of the ribosome . The ribosome itself is a large ribonucleoprotein complex responsible for protein synthesis in the cell, composed of 4 RNA species and approximately 80 structurally distinct proteins . RPL12 has a calculated molecular weight of 17819 Da, though it is often observed at approximately 21 kDa in experimental conditions .

What are the primary applications for RPL12 antibodies in research settings?

RPL12 antibodies are validated for multiple research applications, with the most common being:

• Western Blot (WB): Used for detection and quantification of RPL12 protein in cell lysates and tissue samples. Recommended dilutions typically range from 1:500 to 1:2000 .

• Immunohistochemistry (IHC): Particularly useful for examining RPL12 expression patterns in various tissues. Typical dilutions range from 1:500 to 1:2000 for paraffin-embedded tissues .

• Ribosome profiling studies: RPL12 antibodies can be used to analyze translation dynamics through ribosome density measurements .

• Polysome analysis: To study translation efficiency and mRNA association with ribosomes .

What sample types show reliable reactivity with RPL12 antibodies?

Based on validation data, RPL12 antibodies have demonstrated reliable reactivity with:

These antibodies may also cross-react with bovine and rabbit samples, though this requires further validation in specific experimental contexts .

What is the optimal protocol for using RPL12 antibodies in Western blot applications?

For optimal Western blot results with RPL12 antibodies:

• Sample preparation: Extract proteins using standard lysis buffers containing protease inhibitors.

• Protein separation: Use 10-12% SDS-PAGE gels for optimal resolution of RPL12 (~18 kDa calculated, ~21 kDa observed) .

• Transfer: Standard PVDF or nitrocellulose membranes are suitable.

• Blocking: 5% non-fat milk or BSA in TBST for 1 hour at room temperature.

• Primary antibody incubation: Dilute RPL12 antibody 1:500-1:2000 in blocking buffer. Incubate overnight at 4°C .

• Detection: Use appropriate secondary antibodies and chemiluminescent detection systems.

• Expected band size: Look for a band at approximately 21 kDa .

For each new cell line or tissue type, optimization of antibody concentration is recommended.

How should RPL12 antibodies be stored to maintain optimal activity?

To maintain antibody activity:

• Short-term storage (up to 2 weeks): Refrigerate at 2-8°C in the original container.

• Long-term storage: Store at -20°C in small aliquots to prevent freeze-thaw cycles, which can degrade antibody quality .

• Avoid repeated freeze-thaw cycles by preparing single-use aliquots.

• Most commercial RPL12 antibodies are supplied in PBS with 0.09% (W/V) sodium azide as a preservative .

How can RPL12 antibodies be used in ribosome profiling studies?

Ribosome profiling with RPL12 antibodies can provide insights into translation dynamics:

• Ribosome density (RD) analysis: When combined with RNA-Seq, this approach allows measurement of translation efficiency per transcript. RPL12 can serve as a marker for ribosome occupancy .

• Translation rate assessment: Studies have shown that modulation of RPL12 levels can significantly alter translation rates. For example, when RPL12 is depleted by siRNA, both translation initiation and elongation rates are markedly slowed .

• Experimental approach:

  • Isolate polysomes through sucrose gradient fractionation

  • Use RPL12 antibodies for Western blot analysis to confirm polysome fractions

  • Extract RNA from these fractions for downstream analysis (RNA-Seq, qRT-PCR)

  • Compare relative abundances of specific transcripts between total and polysome-associated RNA pools

This methodology has been successfully employed to examine how RPL12 depletion affects the translation of specific transcripts, with findings suggesting that transcripts with higher GC content are more significantly impacted by changes in RPL12 levels .

What role does RPL12 play in regulating protein folding during translation?

Research using RPL12 manipulation has revealed a critical relationship between translation rate and protein folding:

• RPL12 depletion causes slowed ribosome velocity, which has been shown to enhance folding of certain proteins, particularly those prone to misfolding. For example, in cystic fibrosis research, silencing RPL12 significantly increased F508del-CFTR steady-state expression, interdomain assembly, and baseline open-channel probability .

• Mechanism: The slower translation rate appears to provide additional time for nascent polypeptides to achieve proper folding conformations during synthesis, which is particularly important for complex multi-domain proteins.

• Research applications:

  • Using RPL12 antibodies to monitor RPL12 levels in translation rate modulation experiments

  • Combining RPL12 knockdown with functional assays to assess protein activity

  • Correlating RPL12 levels with folding efficiency of proteins of interest

Studies have demonstrated that when RPL12 was suppressed, F508del-CFTR (a mutant protein involved in cystic fibrosis) showed approximately 7-fold higher levels of ion transport activity compared to controls, maintaining stability during thermal stress tests .

How does RPL12 function differ from other ribosomal proteins in polysome analysis?

When conducting polysome analysis with different ribosomal protein antibodies:

• RPL12 vs. RPL26: Both are components of the 60S subunit but may have different sensitivities in detecting specific polysome populations. RPL26 antibodies have been successfully used in Western immunoblot analysis of polysome fractions .

• RPL12 vs. RPLP0: RPLP0 is another 60S subunit protein that has been used as a marker in polysome analysis. Comparative studies can reveal differential association with specific mRNA populations .

• RPL12 vs. RPS10: RPS10 is a component of the small 40S subunit and can be detected with anti-Sm (Y12) antibodies that cross-react with RPS10. Using both RPL12 and RPS10 antibodies can provide complementary information about ribosome composition across polysome fractions .

• Research applications:

  • Differential polysome profiling

  • Analysis of ribosome composition in specific cellular compartments

  • Comparison of translation complexes under various cellular conditions

How can ribosomal protein antibodies be used to study cell-type-specific translation?

While the search results focus primarily on RPL22 for cell-type-specific studies, similar principles can be applied using RPL12 antibodies:

• The RiboTag methodology, which utilizes epitope-tagged ribosomal proteins (such as HA-tagged RPL22), can be adapted for RPL12 studies. This approach allows for immunoprecipitation of polysomes from specific cell types expressing the tagged ribosomal protein .

• Cell-type-specific translation analysis protocol:

  • Generate constructs expressing tagged RPL12 under cell-type-specific promoters

  • Homogenize tissue containing target cells

  • Immunoprecipitate tagged ribosomes using appropriate antibodies

  • Extract and analyze ribosome-associated mRNAs

• Quality control: Assess the integrity of purified RNA using bioanalyzer analysis, looking for intact 18S and 28S ribosomal RNA peaks. RNA integrity number (RIN) values above 8.0 indicate sufficient quality for downstream applications including microarray, qRT-PCR, and RNA-seq analysis .

What controls should be included when using RPL12 antibodies for polysome immunoprecipitation?

When designing experiments involving RPL12 antibodies for polysome analysis:

• Negative controls:

  • Immunoprecipitation with isotype-matched irrelevant antibodies (e.g., anti-Myc antibodies have been used as controls in similar experiments)

  • Use of tissues or cells not expressing the target protein

  • IgG controls matched to the host species of the primary antibody

• Positive controls:

  • Include analysis of other ribosomal proteins that should co-precipitate with RPL12 (e.g., other 60S subunit components)

  • Verify presence of 18S and 28S rRNA in immunoprecipitated samples

• Validation approaches:

  • Western blot analysis of immunoprecipitated proteins to confirm enrichment of RPL12 and depletion of non-specific proteins

  • qRT-PCR analysis of immunoprecipitated RNA to verify enrichment of ribosome-associated transcripts

  • RNA integrity assessment to ensure sample quality for downstream applications

What are common issues when working with RPL12 antibodies and how can they be resolved?

How can RPL12 antibodies be used in studying translation-related disease mechanisms?

RPL12 antibodies can be valuable tools in studying diseases related to translation dysregulation:

• In cystic fibrosis research: RPL12 silencing has been shown to rescue folding and function of mutant CFTR protein (F508del). RPL12 antibodies can be used to monitor RPL12 levels during siRNA treatments and correlate them with CFTR function .

• Experimental approach:

  • Establish RPL12 knockdown using siRNA

  • Validate knockdown efficiency using RPL12 antibodies in Western blot

  • Measure translation rates through metabolic labeling

  • Assess target protein folding and function

  • Correlate RPL12 levels with functional outcomes

• Findings from previous research: After RPL12 knockdown, F508del-CFTR-dependent ion transport exhibited approximately 7-fold higher levels than controls and remained nearly stable during thermal stress, suggesting that modulation of translational velocity through RPL12 can enhance activity of disease-associated proteins .

How are RPL12 antibodies being used to understand the relationship between translation and RNA processing?

Recent proteomic analysis of polysomes has identified interactions between the translation machinery and RNA processing factors:

• Studies using ribosomal protein antibodies, including those against RPL12, have revealed that mitotic polysomes are enriched with proteins involved in RNA processing, including alternative splicing and RNA export factors .

• Research applications:

  • Co-immunoprecipitation using RPL12 antibodies followed by mass spectrometry to identify interacting RNA processing factors

  • Analysis of how translation rate affects alternative splicing patterns

  • Investigation of mRNP complex composition during various cellular states

• Methodological approach:

  • Isolate polysomes through sucrose gradient fractionation

  • Perform Western blot analysis using RPL12 antibodies to identify polysome-containing fractions

  • Analyze co-precipitating proteins to identify RNA processing factors

  • Validate interactions through reciprocal co-immunoprecipitation experiments

What considerations should be made when selecting between different commercial RPL12 antibodies?

When selecting an RPL12 antibody for research:

• Epitope considerations:

  • Some antibodies target specific regions of RPL12, such as the central region (amino acids 71-100)

  • Consider whether your experimental design might mask or alter the epitope

• Validated applications:

  • Verify that the antibody has been validated for your specific application (WB, IHC, IP)

  • Review published literature using the specific antibody for similar applications

• Species reactivity:

  • Confirm reactivity with your species of interest (human, mouse, rat are commonly validated)

  • For cross-species studies, select antibodies with broad species reactivity

• Clonality considerations:

  • Polyclonal antibodies may offer higher sensitivity but potentially lower specificity

  • Consider the specific research question when choosing between polyclonal and monoclonal options