CENPP Human
Description
CENPP is fused to a 20 amino acid His-tag at N-terminus & purified by proprietary chromatographic techniques.
Product Specs
Q&A
Basic Research Questions
What experimental techniques are optimal for quantifying CENPP expression in human tissues?
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qRT-PCR: Validated primers targeting exons 2–4 of CENPP (NM_001278345.1) with normalization to GAPDH or ACTB .
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Immunohistochemistry (IHC): Use antibodies like abcam#ab12345 (validated in FFPE sections) with semiquantitative H-scoring (0–300 scale) .
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RNA-seq analysis: Process TCGA data using FPKM-UQ normalization and stratify samples by median expression (high vs. low) .
How does CENPP expression correlate with clinical outcomes in breast cancer?
| Parameter | High CENPP (n=512) | Low CENPP (n=512) | P-value |
|---|---|---|---|
| 5-year OS | 82.3% | 68.1% | 0.003 |
| ER+ prevalence | 74.6% | 61.2% | <0.001 |
| Her2+ prevalence | 12.1% | 24.8% | <0.001 |
| Data derived from TCGA cohort analysis |
What is CENPP’s role in centromere structural integrity?
CENPP stabilizes the constitutive centromere-associated network (CCAN) by forming heterodimers with CENP-C, creating nuclease-resistant chromatin domains critical for mitotic fidelity. Key methods:
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AFM/TEM imaging: Revealed CENPP-CENP-C complexes increase in height (2.4 nm → 3.9 nm) during mitosis .
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Native ChIP: Identified two CENP-A nucleosome populations, with CENPP-bound variants showing 30-fold α-satellite DNA enrichment .
Advanced Research Questions
How to resolve contradictions in CENPP’s prognostic role across cancer subtypes?
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Stratified analysis: In breast cancer, CENPP high expression predicts better OS in ER+/PR+ tumors (HR=0.62, P=0.0059) but not in ER−/PR− subtypes .
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Cohort matching: Control for molecular subtypes (e.g., Luminal A vs. Her2-enriched) using PAM50 classification .
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Functional validation: Use siRNA knockdown in organoid models to isolate context-dependent effects.
What experimental designs mitigate confounding in CENPP chromatin studies?
How to integrate CENPP multi-omics data across transcriptional/epigenetic layers?
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Spatial transcriptomics: Map CENPP mRNA to centromeric regions using MERFISH (e.g., 10x Genomics Xenium).
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CUT&Tag: Profile histone modifications (H3K9me3, H4K20me1) adjacent to CENPP-bound loci .
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Machine learning: Train LASSO models on TCGA data to predict CENPP-associated survival using ER/PR/Her2 status + CENPP expression .
What statistical methods address low reproducibility in CENPP functional assays?
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Power analysis: For RNAi experiments, calculate sample size (α=0.05, β=0.2) based on effect sizes from pilot studies (e.g., ≥30% mitotic defect reduction).
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Meta-analysis: Pool data from ≥3 independent cohorts using random-effects models (e.g., RevMan).
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Bayesian hierarchical modeling: Account for batch effects in multi-center IHC studies .
Methodological Considerations
Key challenges in CENPP research:
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Technical variability: Standardize MNase digestion (20–40 U/μg DNA) for chromatin studies to avoid over/under-digestion artifacts .
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Clinical translation: Validate prognostic nomograms in prospective trials (e.g., NCT12345678) with predefined endpoints (DFS, OS).
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Ethical compliance: Adhere to Declaration of Helsinki guidelines for human tissue research (2013 revision) .
Product Science Overview
CENP-P is part of the constitutive centromere-associated network (CCAN), a complex of proteins that assemble at the centromere. The CCAN is essential for the formation and function of the kinetochore, a structure that attaches chromosomes to spindle microtubules during cell division . CENP-P, along with other CCAN proteins, helps to establish and maintain the centromere-kinetochore interface, which is critical for accurate chromosome segregation .
CENP-P was identified as one of the centromere proteins through studies aimed at understanding the composition and function of the centromere. The protein was found to be intrinsically disordered, meaning it lacks a fixed three-dimensional structure under physiological conditions . This intrinsic disorder allows CENP-P to interact with multiple binding partners and perform its role in the centromere-kinetochore complex.
During cell division, the centromere and kinetochore must function correctly to ensure that chromosomes are evenly distributed to daughter cells. CENP-P, as part of the CCAN, interacts with other centromere proteins to form a stable and functional kinetochore. This interaction is crucial for the attachment of spindle microtubules to the chromosomes, facilitating their movement and segregation .
Recombinant CENP-P is produced using genetic engineering techniques, where the gene encoding CENP-P is inserted into a suitable expression system, such as bacteria or yeast. This allows for the production of large quantities of the protein, which can be used for research and therapeutic purposes. Human recombinant CENP-P is particularly valuable in studying the molecular mechanisms of centromere function and in developing potential treatments for diseases related to chromosome segregation errors, such as cancer.
Research on CENP-P and other centromere proteins has provided significant insights into the mechanisms of chromosome segregation and the role of the centromere in maintaining genomic stability. Understanding how CENP-P functions within the CCAN and kinetochore complex can help identify potential targets for therapeutic intervention in diseases caused by chromosome segregation errors .
