RPL17B Antibody

What is RPL17 and what cellular functions does it perform?

RPL17 is a component of the 60S ribosomal subunit involved in protein synthesis. It belongs to the L22P family of ribosomal proteins and is primarily located in the cytoplasm. Ribosomes, the organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit together comprising 4 RNA species and approximately 80 structurally distinct proteins . Beyond its structural role in ribosomes, RPL17 has been discovered to function as a vascular smooth muscle cell (VSMC) growth inhibitor, similar to a tumor suppressor, making it a potential therapeutic target for limiting carotid intima-media thickening .

RPL17 antibodies have demonstrated reactivity across multiple species and sample types:

RPL17 is also expressed in various human tissues including pancreas, lung, colon, cystic duct, gall bladder, kidney, and liver . Expression levels vary significantly between different pancreatic tumor cell lines, with higher expression in well-differentiated lines (HPAF, COLO 357, Capan-1) and lower expression in poorly differentiated lines (HCG-25, PANC-1) .

How does RPL17 expression correlate with cell proliferation in experimental models?

Research has revealed that RPL17 functions as a vascular smooth muscle cell (VSMC) growth inhibitor. In comparing C3HeB/FeJ (C3H/F) and SJL/J (SJL) mouse models, qRT-PCR demonstrated that RPL17 expression in mouse aortic smooth muscle cells (MASMC) was >6-fold higher in C3H/F compared to SJL at passage 4. This expression difference corresponds with reduced cell proliferation in C3H/F mice .

Protein expression analysis showed approximately 2.5-fold higher RPL17 levels in C3H/F compared to SJL MASMC, with similar increases observed in aortic tissue samples. These findings suggest that higher RPL17 expression correlates with reduced vascular smooth muscle cell proliferation, supporting its role as a growth inhibitor .

What methods can be used to modulate RPL17 expression in functional studies?

To demonstrate RPL17's growth inhibitory function in vivo, researchers have successfully used pluronic gel delivery of RPL17 siRNA to carotid arteries. In C3H/F mice, this intervention resulted in an 8-fold increase in the number of proliferating cells, confirming RPL17's role in suppressing cell proliferation .

Additionally, following partial carotid ligation in SJL mice, researchers observed decreased RPL17 expression in the intima and media, which corresponded with increased cell proliferation. These findings provide compelling evidence for RPL17's function as a VSMC growth inhibitor and highlight siRNA-mediated knockdown as an effective approach for studying RPL17 function in vascular biology .

How should discrepancies between calculated and observed molecular weights of RPL17 be interpreted?

Researchers frequently observe differences between calculated and observed molecular weights of RPL17:

These discrepancies may result from post-translational modifications, alternative splicing, or technical variations in gel electrophoresis conditions. When validating antibody specificity, researchers should consider these variations and confirm target identity through additional methods such as mass spectrometry or knockdown studies .

What are the optimal conditions for antigen retrieval in immunohistochemistry using RPL17 antibodies?

For optimal immunohistochemical detection of RPL17 in tissue samples, particularly in human pancreatic cancer tissue, the following antigen retrieval protocols have been validated:

• Primary recommendation: TE buffer pH 9.0

• Alternative method: Citrate buffer pH 6.0

The selection between these protocols may depend on tissue type, fixation method, and specific experimental requirements. Researchers should validate and optimize these conditions for their particular sample types .

What are the recommended storage conditions for maintaining RPL17 antibody stability and activity?

For optimal preservation of RPL17 antibody activity, the following storage recommendations should be followed:

For -20°C storage, aliquoting is generally unnecessary. Small volume preparations (20μl) may contain 0.1% BSA as a stabilizer. Maintaining proper storage conditions is crucial for preserving antibody specificity and sensitivity in experimental applications .

How can western blot protocols be optimized for detecting RPL17 in different sample types?

For optimal western blot detection of RPL17 in various sample types, consider the following recommendations:

• Sample preparation: Total protein extraction from tissues (pancreas, liver, lung) or cell lines (HeLa, HepG2) using standard lysis buffers containing protease inhibitors

• Sample loading: 20-50 μg of total protein per lane

• Dilution optimization: Test a dilution series (1:2000 to 1:10000) to determine optimal signal-to-noise ratio for specific sample types

• Secondary antibody: HRP-conjugated anti-rabbit IgG at 1:10000 dilution

• Detection system: Enhanced chemiluminescence (ECL)

When analyzing expression differences between samples, researchers should use appropriate housekeeping controls and quantitative densitometry for accurate comparison .

How is RPL17 expression altered in vascular disease models, and what are the implications?

In carotid injury models, RPL17 expression patterns demonstrate significant relevance to intima formation and vascular smooth muscle cell proliferation. Following partial carotid ligation in SJL mice, researchers observed decreased RPL17 expression in the intima and media corresponding with increased cell proliferation .

This inverse relationship between RPL17 expression and vascular cell proliferation suggests RPL17 functions as a natural inhibitor of intima-media thickening, a process associated with increased cardiovascular risk in humans. Consequently, therapeutic approaches aimed at enhancing or maintaining RPL17 expression or function may represent a novel strategy for preventing pathological vascular remodeling .

What expression patterns of RPL17 have been observed across different pancreatic cancer cell lines?

RPL17 expression varies significantly across pancreatic cancer cell lines with different differentiation states:

This expression pattern suggests RPL17 may play different roles depending on tumor differentiation status and could potentially serve as a marker or therapeutic target in pancreatic cancer research .

What controls should be included when validating RPL17 antibody specificity?

To ensure experimental validity when working with RPL17 antibodies, researchers should implement the following controls:

• Positive controls: Include validated cell lines or tissues known to express RPL17 (HeLa cells, HepG2 cells, pancreatic tissue)

• Negative controls: Include primary antibody omission controls and tissues/cells with confirmed low expression

• Knockout/knockdown validation: Where possible, include RPL17 knockdown samples to confirm specificity

• Peptide competition assays: Pre-incubation of antibody with immunizing peptide should abolish specific signal

• Multiple antibody validation: When critical, confirm findings with an alternative antibody targeting a different epitope of RPL17

These controls help ensure that experimental observations reflect genuine RPL17 biology rather than technical artifacts or cross-reactivity .

How should researchers address inconsistent results when detecting RPL17 in different experimental systems?

When facing inconsistent results in RPL17 detection across different experimental systems, researchers should consider:

• Antibody titration: As recommended in product documentation, "this reagent should be titrated in each testing system to obtain optimal results"

• Sample-dependent optimization: Results may be "sample-dependent," requiring adjustment of protocols for specific tissue or cell types

• Antigen retrieval variations: For IHC applications, test both TE buffer pH 9.0 and citrate buffer pH 6.0 for optimal epitope exposure

• Alternative splice variants: Consider that "alternative splicing results in multiple transcript variants" of RPL17, which may affect detection in different systems

• Post-translational modifications: Differences between calculated (21 kDa) and observed (23 kDa) molecular weights suggest modifications that may vary between experimental systems

Systematic troubleshooting with appropriate controls and documentation of optimized conditions for each experimental system will enhance reproducibility and reliability of RPL17-focused research .