MAPT (Ab-717/400) Antibody

Basic Research Questions

• What is MAPT (Ab-717/400) Antibody and what epitope does it recognize?

MAPT (Ab-717/400) Antibody is a rabbit polyclonal antibody that recognizes the microtubule-associated protein tau (MAPT) around the phosphorylation site of serine 717/400. The specific epitope sequence is V-V-S(p)-G-D. This antibody was developed using a synthesized non-phosphopeptide derived from human Tau protein . As a polyclonal preparation, it contains a heterogeneous mixture of antibodies that recognize multiple epitopes within the target region, providing robust detection capabilities for total Tau protein.

The antibody targets the tau protein (UniProt ID: P10636, NCBI Gene ID: 4137), which plays a critical role in microtubule stability and neuronal polarity .

• What are the validated applications for MAPT (Ab-717/400) Antibody?

The MAPT (Ab-717/400) Antibody has been experimentally validated for the following applications:

Western blot analysis using extracts from rat brain cells has confirmed the specificity and sensitivity of this antibody for detecting endogenous levels of total Tau protein .

• What species reactivity does MAPT (Ab-717/400) Antibody exhibit?

Based on sequence homology and experimental validation, MAPT (Ab-717/400) Antibody demonstrates cross-reactivity with:

• Human (Identities = 100%, Positives = 100%)

• Mouse (Identities = 100%, Positives = 100%)

• Rat (Identities = 100%, Positives = 100%)

This high degree of reactivity across species makes the antibody particularly valuable for comparative studies of tau protein function and pathology in different experimental models .

• What is the functional significance of Tau protein targeted by this antibody?

Tau protein (MAPT) serves several critical neuronal functions:

• Promotes microtubule assembly and stability

• Functions in the establishment and maintenance of neuronal polarity

• Acts as a linker protein between axonal microtubules (C-terminus binding) and neural plasma membrane components (N-terminus binding)

• Determines axonal polarity through its localization in the neuronal cell body domain defined by the centrosome

• Contains isoforms with differential functions: shorter isoforms allow cytoskeletal plasticity while longer isoforms contribute to stabilization

These functions have been established through seminal research by Goedert (1988, 1989) and Lee (1989) .

Advanced Research Questions

• What methodological considerations are important when using MAPT (Ab-717/400) Antibody for Western Blotting?

For optimal Western Blot results with MAPT (Ab-717/400) Antibody, researchers should consider:

Sample Preparation:

• Fresh brain tissue extracts provide optimal results

• Rapid extraction and processing in cold conditions helps preserve phosphorylation states

• Use phosphatase inhibitors in lysis buffer to maintain native phosphorylation status

Protocol Optimization:

• Initial dilution recommendation: 1:500-1:3000, but should be empirically optimized

• Extended blocking (3% BSA in TBST, 1-2 hours) reduces background

• Overnight primary antibody incubation at 4°C improves sensitivity

• Signal detection systems should be matched to expected expression levels

Controls:

• Include brain lysate as a positive control

• Perform peptide competition assay to confirm specificity

• Consider including a phosphorylation control (e.g., λ-phosphatase treated sample)

Western blot analysis has been successfully performed using rat brain cell extracts, demonstrating the antibody's efficacy in detecting endogenous tau protein levels in neural tissue samples .

• How can MAPT (Ab-717/400) Antibody be utilized in neurodegenerative disease research?

MAPT (Ab-717/400) Antibody offers several valuable applications in neurodegenerative research:

Pathological Studies:

• Detection of tau aggregation in tauopathies (Alzheimer's disease, frontotemporal dementia)

• Assessment of tau pathology progression in disease models

• Evaluation of neurofibrillary tangle formation

Therapeutic Development:

• Screening potential tau-targeting compounds

• Monitoring tau phosphorylation changes in response to drug treatments

• Evaluating effectiveness of phosphorylation inhibitors

Mechanistic Investigations:

• Studying tau's interaction with microtubules in disease states

• Examining tau's role in axonal transport disruption

• Investigating relationships between tau and other neurodegenerative proteins

The antibody's specificity for total tau protein makes it particularly useful for establishing baseline tau levels before examining specific phosphorylation events that may contribute to pathology .

• What are the optimal storage and handling procedures for maintaining MAPT (Ab-717/400) Antibody activity?

To maintain antibody integrity and performance:

Storage Conditions:

• Store at -20°C or -80°C for long-term stability

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

• When shipped at 4°C, promptly aliquot upon delivery

Buffer Composition:
The antibody is supplied in phosphate buffered saline (without Mg²⁺ and Ca²⁺), pH 7.4, containing:

• 150mM NaCl

• 0.02% sodium azide (preservative)

• 50% glycerol (cryoprotectant)

Stability Considerations:

• Working dilutions should be prepared fresh before use

• Avoid contamination to prevent microbial growth

• Protect from prolonged light exposure, particularly if using fluorescent secondary antibodies in subsequent applications

Following these procedures will help maintain antibody activity throughout the research project timeline.

• What are potential cross-reactivity concerns with MAPT (Ab-717/400) Antibody?

While MAPT (Ab-717/400) Antibody demonstrates high specificity, researchers should consider:

Potential Cross-Reactivity:

• Other microtubule-associated proteins with similar phosphorylation motifs

• Proteins containing the V-V-S-G-D amino acid sequence

• MAP2 family proteins (which share structural similarities with tau)

Minimizing Cross-Reactivity Issues:

• Perform control experiments with recombinant tau proteins

• Include blocking peptides corresponding to the immunogenic sequence

• Consider Western blot analysis to confirm single-band specificity at the expected molecular weight

• Use tau knockout/knockdown samples as negative controls when possible

The antibody has been affinity-purified using epitope-specific immunogen, which significantly reduces non-specific binding while maintaining sensitivity for total tau protein detection .

• How does phosphorylation state affect detection with MAPT (Ab-717/400) Antibody?

Understanding the relationship between tau phosphorylation and antibody detection is critical:

Phosphorylation Considerations:

• The antibody was raised against a non-phosphopeptide derived from the region around the serine 717/400 phosphorylation site

• It primarily detects total tau protein rather than specifically targeting phosphorylated forms

• This allows for baseline tau quantification independent of phosphorylation status

Experimental Implications:

• Suitable for measuring total tau levels before examining specific phosphorylation events

• Can serve as a normalization control when using phospho-specific tau antibodies

• May exhibit some preference for non-phosphorylated forms of the epitope region

Comparative Analysis:
When studying phosphorylation-specific events, researchers should:

• Use MAPT (Ab-717/400) Antibody in conjunction with phospho-specific antibodies

• Perform parallel blots with both antibody types

• Calculate phosphorylation ratios by normalizing phospho-specific signals to total tau signals

• What are recommended troubleshooting approaches for common issues with MAPT (Ab-717/400) Antibody?

When encountering challenges with MAPT (Ab-717/400) Antibody applications:

Weak or No Signal:

• Increase antibody concentration (try 1:500 or higher concentration)

• Extend primary antibody incubation time (overnight at 4°C)

• Enhance detection system sensitivity (ECL Plus or similar enhanced chemiluminescence)

• Verify sample integrity and protein concentration

• Ensure proper transfer during Western blotting

High Background:

• Increase blocking duration and concentration (5% BSA or milk)

• Add 0.1% Tween-20 to wash buffers

• Extend washing steps (5 washes, 5 minutes each)

• Dilute primary antibody further

• Try alternative blocking agents (casein or commercial blockers)

Multiple Bands:

• Optimize sample preparation to reduce proteolysis (add protease inhibitors)

• Adjust gel percentage to better resolve tau isoforms (8-10% polyacrylamide)

• Consider phosphatase treatment to eliminate phosphorylation-dependent migration differences

• Verify specificity with peptide competition assays

• How can MAPT (Ab-717/400) Antibody be integrated with other techniques for comprehensive tau pathology studies?

MAPT (Ab-717/400) Antibody can be incorporated into multi-modal research approaches:

Complementary Techniques:

• Immunohistochemistry: Localize tau distribution in tissue sections

• Immunoprecipitation: Isolate tau protein complexes for interaction studies

• Mass spectrometry: Identify tau post-translational modifications and binding partners

• Proximity ligation assay: Investigate tau interactions with other proteins in situ

Integrated Research Strategies:

• Combine Western blot with immunofluorescence microscopy to correlate protein levels with cellular localization

• Pair with cellular fractionation to assess tau distribution between cytoskeletal and soluble compartments

• Use with phospho-specific antibodies in parallel to create comprehensive phosphorylation profiles

Advanced Applications:

• Super-resolution microscopy using immunofluorescence to visualize tau assemblies

• Live cell imaging with fluorescently tagged secondary antibodies (following fixation and permeabilization)

• Electron microscopy immunogold labeling for ultrastructural localization

• What are the comparative advantages of using polyclonal versus monoclonal antibodies for tau detection?

When considering antibody selection for tau research:

Polyclonal Advantages (MAPT Ab-717/400):

• Recognizes multiple epitopes within the target region

• Generally higher sensitivity due to multiple binding sites

• More tolerant of minor protein denaturation or conformational changes

• Better for detecting native proteins and low-abundance targets

Polyclonal Limitations:

• Batch-to-batch variation may require standardization

• Potentially higher background in some applications

• May exhibit some cross-reactivity with highly similar epitopes

When to Choose MAPT (Ab-717/400) Polyclonal Antibody:

• For maximum detection sensitivity of total tau protein

• When studying native protein conformation

• When investigating protein-protein interactions

• For initial characterization studies before moving to epitope-specific monoclonals

Optimization Strategy:
Researchers may benefit from using MAPT (Ab-717/400) polyclonal antibody for total tau detection while employing monoclonal antibodies for specific phosphorylation sites or conformational epitopes in parallel experiments .