The term "PAE9" in the provided sources refers exclusively to PAE9 (Pectin Acetylesterase 9), an enzyme involved in plant cell wall acetate metabolism. This protein removes acetyl groups from pectin polysaccharides in Arabidopsis leaves, impacting cell wall structure and plant morphology (source ). No antibodies targeting PAE9 or named "PAE9 Antibody" are documented in the search results.
While "PAE9 Antibody" is not covered, several antibody-related compounds and concepts are discussed. Below is a synthesis of relevant data:
Antibodies are Y-shaped proteins composed of two heavy chains and two light chains (sources , , ). Key regions include:
Fab fragment: Antigen-binding region (comprising variable domains of heavy/light chains).
Fc region: Mediates effector functions (e.g., complement activation, ADCC) (sources , , ).
| Antibody Component | Function | Key Features |
|---|---|---|
| Heavy Chains (e.g., IgG, IgA) | Determine class/isotype | Contain constant regions (Cγ, Cα) and hinge regions |
| Light Chains (κ or λ) | Contribute to antigen specificity | Variable domains (VL) form paratopes |
| Fc Region | Effector activity | Contains domains for receptor binding (e.g., FcγRIII) |
Polyclonal antibodies (PCAs) recognize multiple epitopes on a target antigen, while monoclonal antibodies (mAbs) bind a single epitope (source ).
| Type | Advantages | Applications |
|---|---|---|
| Polyclonal | Broad specificity, high sensitivity | Diagnostics (e.g., ELISA), research (protein localization) |
| Monoclonal | High specificity, reproducibility | Therapeutics (e.g., checkpoint inhibitors), targeted drug delivery |
Approved and experimental antibodies are listed in sources and . Examples include:
Ebronucimab (PCSK9 inhibitor): Used for hypercholesterolemia.
Epcoritamab (CD20/CD3 bispecific): Targets diffuse large B-cell lymphoma.
| Antibody Name | Target | Class | Mechanism |
|---|---|---|---|
| Ebronucimab | PCSK9 | Full-length IgG1 | LDL cholesterol reduction |
| Epcoritamab | CD20/CD3 | Bispecific IgG1 | T-cell recruitment to cancer cells |
AAV9 Antibodies: Source discusses anti-AAV9 antibodies (against adeno-associated virus serotype 9), which are relevant to gene therapy safety. These are distinct from PAE9.
PAE Cells: Source references porcine aortic endothelial (PAE) cells, used in retroviral infection studies.
Since no data exists on "PAE9 Antibody," consider:
PAE9 (PECTIN ACETYLESTERASE9) plays critical roles in plant immunity and cell wall dynamics, while antibody validation methodologies are essential for studying such proteins. Below are structured FAQs addressing academic research challenges and methodologies related to PAE9 antibody applications, integrating experimental design principles and data interpretation strategies from peer-reviewed studies.
Adopt a CRISPR/Cas9 knockout (KO) validation pipeline:
Cell line selection: Use PaxDB proteomic databases to identify high PAE9-expressing systems (e.g., Arabidopsis cell cultures) .
KO generation: Create PAE9 KO lines and confirm via sequencing.
Immunoblot screening: Compare parental and KO lysates. Validated antibodies should show signal loss in KOs (Fig. 1 in ).
Cross-validation: Apply secondary methods like immunofluorescence (IF) or immunoprecipitation (IP) to confirm localization or interaction partners .
| Assay Type | Expected Result (KO vs. WT) | Common Pitfalls |
|---|---|---|
| Immunoblot | Band disappearance | Non-specific cross-reactivity |
| IF | Localization pattern loss | Autofluorescence |
| IP-MS | Absence of target in eluate | Non-specific binding |
Scenario: An antibody labels PAE9 in immunoblots but fails to rescue pae9 mutant phenotypes.
Step 1: Verify antibody-epitope specificity using peptide blocking assays or epitope mapping.
Step 2: Quantify PAE9 protein levels in mutants via parallel reaction monitoring (PRM) mass spectrometry.
Step 3: Assess compensatory mechanisms. For example, pae9 mutants upregulate WRKY51 suppressors under aphid infestation, restoring JA signaling despite low baseline JA .
The PASA (Proteomic Analysis of Serum Antibodies) pipeline enables:
Antigen-specific peptide mapping: Identify PAE9-binding antibodies via LC-MS/MS, filtering for ≥5-fold enrichment in elution vs. flow-through fractions .
BCR-Seq integration: Map peptides to clonal BCR sequences to link antibody specificity to genetic lineages.
Quantitative analysis: Use MaxQuant for intensity-based profiling and correlate with transcriptomic data (e.g., PAE9 expression levels across tissues) .
CDRH3-specific peptide matches for clone tracking.
Isoform distribution heatmaps (IgG1 vs. IgG2 dominance).
PAE9-associated oxidative stress alters epitope accessibility:
Pre-treatment optimization: Include 10 mM DTT in extraction buffers to reduce disulfide bonds masking PAE9 epitopes .
Antioxidant interference: Avoid ascorbic acid in buffers, as it quenches phenolic compounds linked to PAE9 activity .
Validation: Compare antibody signals in oxidative (H₂O₂-treated) vs. reduced samples to assess redox-dependent binding.
Transcriptomics: Identify PAE9-coexpressed defense genes (e.g., PAD3, IGMT2) via WGCNA .
Metabolomics: Quantify JA, camalexin, and glucosinolates in PAE9-immunoprecipitated samples.
Microbiome integration: Profile aphid salivary effectors via metatranscriptomics to identify PAE9-targeting proteins .
Data integration challenge: Use mixed-effects models to distinguish direct PAE9 functions from microbiome-mediated effects.