MPZ Antibody
Description
Structure and Function of MPZ
MPZ, also known as P0, is a 28-kDa type I transmembrane glycoprotein belonging to the immunoglobulin superfamily . It is synthesized by Schwann cells and forms tetramers that stabilize the multilamellar myelin sheath through homophilic adhesion . Mutations in the MPZ gene are linked to demyelinating neuropathies, including Charcot-Marie-Tooth disease type 1B (CMT1B) and Dejerine-Sottas syndrome .
Key Properties
| Property | Description |
|---|---|
| Molecular Weight | 28–30 kDa |
| Host Species | Rabbit, Chicken (polyclonal) |
| Reactivity | Human, Mouse, Rat |
| Immunogen | MPZ fusion protein (Ag0848) |
Applications of MPZ Antibody
The antibody is widely used in molecular biology for studying myelin formation and neuropathies.
Primary Applications
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Western Blot (WB): Detects MPZ in lysates of Schwann cells and peripheral nerve tissues, with optimal dilutions ranging from 1:500 to 1:2000 .
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Immunohistochemistry (IHC): Stains myelinating Schwann cells in nerve sections, requiring antigen retrieval with TE buffer (pH 9.0) .
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Immunofluorescence (IF): Visualizes MPZ localization in fixed cells .
Published Uses
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CMT1B Research: Used to confirm MPZ mutations in patient-derived cells .
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Enhancer Studies: A variant in the MPZ intronic enhancer (c.126-1086T>A) reduces transcriptional activity by 60% in vitro .
Research Insights
Product Specs
Target Background
- A novel MPZ base-pair substitution in the family is associated with inherited distal demyelinating neuropathy and should be reclassified as pathogenic for Charcot-Marie-Tooth disease. PMID: 29465609
- In a Chinese Han population, six novel Charcot-Marie-Tooth disease-associated gene mutations of MPZ (c.440T>C) were identified. PMID: 27862672
- Research suggests that the protein with the I30T mutation exhibits variable structural conformation and dynamic behavior compared to the native and mutant I30M of MPZ protein. PMID: 26135405
- Mutations D6Y, D32G, and H52Y, responsible for late-onset forms of the human disease, impair interaction with neurofascins. PMID: 26406915
- A correlation exists between the genotype of MPZ mutations and the phenotype of Charcot Marie Tooth Disease. PMID: 26310628
- Two heterozygous missense mutations were identified in 38 Italian CMT2 patients. PMID: 24819634
- P0 protein in serum may serve as an early effective biomarker for peripheral nerve neuropathy. PMID: 24762602
- Haplotype analysis based on ten markers (seven SNPs, two microsatellites, and an intronic polyA stretch) suggests a founder effect hypothesis for this allele migration. PMID: 25720167
- This study demonstrated that the MPZ mutation c.419C>G exhibits a relatively late onset and slowly progressive CMT1 phenotype. PMID: 24028194
- This study revealed a mutation of MPZ in a patient with Charcot-Marie-Tooth disease. PMID: 23743332
- This mutation is particularly significant because it implicates the importance of the immunoglobulin-like structure of MPZ protein. PMID: 22633464
- MPZ-related neuropathy should be considered in the diagnostic workup of patients with painful axonal neuropathy. PMID: 23279346
- The p.Arg106Cys allele in MPZ causes late-onset, predominantly axonal sensory and motor neuropathy. PMID: 22222859
- A report details two siblings presenting with early-onset severe Charcot-Marie-Tooth disease. A novel heterozygous C to T base substitution at nucleotide position 199 (c.199C>T) was identified in exon 2 of MPZ, resulting in the substitution of arginine for cysteine at codon 67 (p.Arg67Cys). PMID: 23197742
- Myelin protein zero is a crucial structural component of compact myelin, and over 100 mutations in this protein have been reported. These mutations can lead to neuropathies with axonal, demyelinating, or other features, encompassing a range of severity. PMID: 22704856
- Patients with CMT1B caused by Ser63del MPZ exhibit a classical CMT1 phenotype that is significantly less severe than that observed in patients with Arg98Cys MPZ. PMID: 22734905
- This study demonstrated that two affected members of the same family with the same genotype had an 8-base pair deletion, c.160_167delTCCCGGGT, in MPZ exon 2. PMID: 22622165
- Myelin protein P0 is a major Aire-regulated peripheral nervous system antigen, demonstrating defective tolerance to P0 in both Aire-deficient mice and humans. PMID: 22490868
- L-MPZ, a novel isoform of myelin P0, is produced by stop codon readthrough. PMID: 22457349
- The overall frequency of MPZ mutation was 0.58% in a Greek population of Charcot-Marie-Tooth type 1. PMID: 22243284
- New allelic variants of hereditary motor-sensor neuropathy caused by mutations in the MPZ (P0) gene are described. PMID: 22433810
- This study expanded the spectrum of MPZ mutations and revealed two distinct mechanisms of MPZ mutations associated with a typical Charcot Marie Tooth 1b phenotype. PMID: 22018721
- The crystal structure of the extracellular domain of human MPZ fused with maltose binding protein is described. PMID: 21971831
- MPZ plays a critical role in a family with 6 affected members across 3 consecutive generations, presenting with motor and sensory demyelinating polyneuropathy. PMID: 22275255
- Charcot-Marie-Tooth disease has been documented in a large Norwegian family caused by a copy number variation in myelin protein zero. PMID: 21787890
- The identified mutation in MPZ may be the underlying cause of Charcot-Marie-Tooth disease in this family. PMID: 21503568
- This study presents, for the first time, morphological data obtained in two sural nerve biopsies indicating a hypomyelination-dysmyelination process in a family carrying the Pro132Leu mutation in the myelin protein zero gene. PMID: 21107784
- A rare myelin protein zero (MPZ) variant alters enhancer activity in vitro and in vivo. PMID: 21179557
- Five patients with four novel MPZ mutations were identified through molecular genetic testing. PMID: 20556410
- Cells expressing mutant P(0), compared to those expressing wild-type P(0), demonstrated varying degrees of reduction in cell adhesiveness. PMID: 20461396
- Two new MPZ mutations causing congenital hypomyelinating neuropathies were identified: c.368_382delGCACGTTCACTTGTG (in-frame deletion of five amino acids) and c.392A>G, Asn131Ser. PMID: 20621479
- Phenotypes associated with each of the new mutations include severe hereditary motor and sensory neuropathy type III, and a mild phenotype CMT1B presented with only decreased or absent reflexes, foot deformities, and mild or absent lower limb atrophies. PMID: 20456450
- A novel frameshift mutation affecting the transmembrane domain (Leu144fs) was identified in a patient with Charcot-Marie-Tooth disease presenting with late-onset, remitting neurological symptoms. PMID: 20516806
- Charcot-Marie-Tooth disease with intermediate conduction velocities was caused by a novel mutation in the MPZ gene. PMID: 20544920
- The results of this study concluded that the ARG98HIS MPZ mutation may cause hereditary and relatively mild and asymmetric demyelinating sensorimotor polyneuropathy. PMID: 20215982
- The index patient of this family with an unusual Charcot-Marie-Tooth phenotype was found to have a missense mutation within the intracellular domain of myelin protein zero. PMID: 19882637
- Mutations in MPZ may play a role in Charcot-Marie-Tooth disease type 1B [case report]. PMID: 19475438
- This study describes an unusual presentation of the Val102fs mutation characterized by symptoms of spinal root hypertrophy with no overt peroneal muscular atrophy. This report provides additional data regarding the clinical presentations of MPZ mutations. PMID: 19906531
- A novel mutation was identified in vocal cord paralysis. PMID: 19950375
- Research suggests that the clinical features associated with MPZ mutations partially depend on the nature of the amino acid change. PMID: 19293842
- Data indicate that the CMT1Adup, GJB1, MPZ, and PMP22 mutation frequencies were within the range reported in other CMT patient cohorts with different ethnic backgrounds. PMID: 19259128
- SSCP analysis was performed for this gene in Croatian patients. PMID: 12211648
- It is proposed that axonal and demyelinating forms of CMT are not distinct categories but rather part of a spectrum of genotypically related conditions, particularly with some MPZ mutations. PMID: 12911457
- DNA sequencing analysis revealed the Asn131Lys mutation in the myelin protein zero gene in three members of an affected family. PMID: 12940837
- This study demonstrates that autonomic disturbances may be a significant clinical sign associated with CMT secondary to MPZ gene mutation in codon 124 (Thr124Met mutation). PMID: 12948789
- A novel mutation, Thr65Ala, in the MPZ gene was identified in a patient with Charcot-Marie-Tooth type 1B disease with focally folded myelin. PMID: 15036333
- Four missense mutations and one 4-base pair (bp) deletion were identified in five patients, one of which, c.173 T>A, had not been previously reported. PMID: 15050444
- MPZ gene screening should be performed for a wide phenotype spectrum of Charcot-Marie-Tooth disease. PMID: 15094849
- Chronic cough was associated with a Thr124 Met mutation. MPZ appears to be crucial for maintaining axonal function in addition to its role in myelin. All MPZ mutations associated with tonic pupils affect the same region of the extracellular domain. PMID: 15159512
- A novel Thr124Lys mutation in the MPZ gene is associated with congenital neuropathy with hypomyelination. PMID: 15184631
Q&A
How should researchers validate MPZ antibody specificity for peripheral nerve myelin studies?
Validation requires a multi-step approach:
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Knockout Controls: Use tissue from MPZ knockout mice to confirm absence of signal in Western blot (WB) or immunohistochemistry (IHC) .
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Peptide Blocking: Pre-incubate the antibody with immunizing peptides (e.g., residues 30–248 of human MPZ) to verify loss of signal .
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Cross-Validation: Compare results with alternative antibodies from different hosts (e.g., chicken IgY vs. rabbit IgG) targeting non-overlapping epitopes .
Table 1: Validation parameters for common MPZ antibodies
| Host Species | Epitope Region | Recommended Dilution (WB/IHC) | Cross-Reactivity |
|---|---|---|---|
| Chicken | Shared mouse/human | 1:2,000–1:5,000 (WB) | Human, Mouse |
| Rabbit | Extracellular domain | 1:500–1:2,000 (IHC) | Human, Mouse, Rat |
What factors influence MPZ antibody performance in paraffin-embedded vs. frozen tissues?
Performance differences arise from:
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Fixation Artifacts: Prolonged formalin fixation masks epitopes; antigen retrieval using citrate buffer (pH 6.0) at 95°C for 20 min restores MPZ detection .
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Epitope Stability: Antibodies targeting cytoplasmic domains (e.g., residues 186–215) show better resilience to fixation than those recognizing extracellular regions .
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Autofluorescence Mitigation: Use TrueBlack® Lipofuscin Autofluorescence Quencher in frozen sections to reduce background noise during immunofluorescence .
How do researchers distinguish MPZ isoforms in Western blot analysis?
MPZ migrates at 28 kDa under reducing conditions . Isoforms generated via stop codon readthrough exhibit minor bands at ~30 kDa. To resolve:
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Use 12% Tris-glycine gels for optimal separation.
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Include lysates from MPZ-transfected HEK293 cells as positive controls .
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Validate with siRNA knockdown in Schwann cell cultures to confirm isoform specificity .
What strategies resolve conflicting MPZ localization data across studies?
Contradictions often stem from:
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Antibody Clonality: Polyclonal antibodies (e.g., chicken IgY) detect broader epitopes but may show non-specific binding compared to monoclonals .
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Compartment-Specific Staining: Nuclear MPZ signals in some reports likely represent cross-reactivity with phosphorylated epitopes. Block with 5% BSA/0.1% Tween-20 to reduce false positives .
Key Validation Steps:
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Quantitative mass spectrometry of immunoprecipitated proteins .
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Colocalization with myelin basic protein (MBP) using confocal microscopy .
How can epitope mapping refine MPZ antibody selection for mutation studies?
MPZ mutations (e.g., G134R, D61Y) disrupt specific structural domains:
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Extracellular Domain Antibodies (e.g., Boster A00997-1): Fail to detect mutations altering glycosylation at N-glycosylation sites (Asn45, Asn105) .
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Cytoplasmic Tail-Targeting Antibodies (e.g., ABIN953494): Retain binding to mutants affecting adhesion but lose reactivity in phosphorylation-deficient mutants (Ser181Ala) .
Table 2: Antibody-epitope compatibility for common MPZ mutations
What methodologies address MPZ antibody cross-reactivity in cross-species studies?
While most antibodies recognize human/mouse MPZ , primate studies require:
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Phylogenetic Alignment: Verify epitope conservation using tools like Clustal Omega. For example, rabbit anti-human MPZ (AA 30–153) shares 98% identity with macaque homologs but only 87% with marmosets .
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Xenotransplant Validation: Inject human Schwann cells into rodent nerves and compare antibody labeling patterns .
How do post-translational modifications impact MPZ antibody binding?
MPZ undergoes phosphorylation (Ser181, Tyr185) and glycosylation, which alter antibody accessibility:
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Glycosylation Effects: Deglycosylate lysates with PNGase F prior to WB to unify migration patterns .
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Phospho-Specific Assays: Use Phos-tag™ gels (5 μM) to separate phosphorylated isoforms detected by cytoplasmic domain antibodies .
Methodological Best Practices
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Lot-to-Lot Consistency Testing: Compare new antibody lots against archived positive controls using standardized lysates .
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Multiplex Validation: Combine MPZ IHC with RNAscope® probes for MPZ mRNA to confirm protein-RNA correlation .
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Dynamic Range Optimization: For quantitative WB, use recombinant MPZ (0.1–10 ng) to generate calibration curves and determine linear detection ranges .
