AG Antibody
Description
Antibody Fundamentals
Antibodies (immunoglobulins) are Y-shaped proteins produced by B cells to neutralize pathogens. They consist of two heavy chains and two light chains, forming a structure with variable regions (paratopes) that bind antigens with high specificity .
Antigen-Antibody Interaction Mechanisms
Antigen-antibody binding involves weak, non-covalent interactions (e.g., hydrogen bonds, van der Waals forces) between epitopes (antigen regions) and paratopes . Key properties:
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Specificity: Governed by hypervariable complementarity-determining regions (CDRs) .
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Affinity maturation: Somatic hypermutation improves binding strength by 10- to 100-fold .
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Cross-reactivity: Occurs when antibodies bind structurally similar epitopes, contributing to autoimmune conditions .
AACDB (Antigen-Antibody Complex Database)
AgAbDb (Antigen-Antibody Interaction Database)
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Function: Maps residue-level interactions (hydrogen bonds, salt bridges) across 403+ complexes .
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Applications: Benchmarking epitope prediction algorithms and antibody humanization .
Antibody Diversity Generation
Diverse antibody repertoires (>10¹¹ specificities) arise through:
Research Challenges and Innovations
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Interface prediction: Machine learning models trained on 4,638 Ab-Ag structures struggle with hydrophobic/hydrogen bond balance .
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Nanotechnology integration: Antibody-conjugated nanoparticles show promise in targeted drug delivery and MRI contrast enhancement .
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Error rates: ~15% of PDB antigen-antibody entries require manual correction in AACDB .
Clinical and Industrial Applications
| Field | Antibody Use Case | Example |
|---|---|---|
| Diagnostics | ELISA, lateral flow assays | HIV detection via gp120 binding |
| Therapeutics | Monoclonal antibodies (e.g., trastuzumab) | HER2-positive breast cancer |
| Vaccine Design | Epitope mapping for synthetic vaccines | SARS-CoV-2 spike protein targets |
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
- Research findings suggest that AGAMOUS functions to maintain the irreversible state of reproductive development through the negative regulation of floral meristem identity genes and genes involved in organ initiation. PMID: 29218596
- AP2 does not repress the transcription of AG in the inner two whorls but instead counteracts AG activity. PMID: 27604611
- ARF3 integrates the functions of AGAMOUS and APETALA2 in floral meristem determinacy. PMID: 25187180
- The ULT1 and LFY pathways act separately in regulating identity and determinacy at the floral meristem. Notably, they independently induce AG expression in the center of the flower to terminate meristem activity. PMID: 25288633
- FLK and PEP physically interact with proteins involved in AG pre-mRNA processing to ensure correct AG function in the floral meristem and flower. PMID: 25658099
- AGAMOUS directly represses WUS expression by binding to the WUS locus and recruiting, directly or indirectly, PcG that methylates histone H3 Lys-27 at WUS. PMID: 22028461
- A model proposes that the decision of whether stamens or petals develop is based on the balance between AP2 and AG activities, rather than the two being mutually exclusive. PMID: 20876650
- The floral phenotype of bellringer mutants is caused by derepression of AG, suggesting that BLR functions as a transcription repressor. PMID: 15155890
- AG activates biosynthesis of gibberellin, which has been proposed to promote the shift from meristem identity to differentiation. PMID: 15634696
- AG and miR172 have distinct functions in flower development and largely act independently in the negative regulation of AP2. PMID: 17573799
- These results indicate that stamen identity and differentiation control by AG is achieved by the regulation of different transcriptional cascades in different floral stages. PMID: 17981996
- Transgenic Arabidopsis plants harboring two tissue-specific promoters, fAGIP and rAGIP in forward and reverse orientations, fAGIP::GUS or rAGIP::GUS displayed similar GUS expression specifically in carpel and stamen tissues and their primordial cells. PMID: 18256838
- PERIANTHIA (PAN) plays a role in regulating stem cell fate by directly controlling AG expression, suggesting that this activity is spatially restricted to the centermost region of the AG expression domain. PMID: 19395638
- Upon enhanced central AG expression, the C-domain laterally expands, necessitating tuning of the expression level of C-function genes in the wild type. PMID: 19554348
