MNS5 Antibody
Description
Introduction to MNS5
MNS5 (AT1G27520 in Arabidopsis thaliana) is a soluble endoplasmic reticulum (ER)-resident enzyme critical for trimming mannose residues on misfolded glycoproteins. It collaborates with MNS4 to regulate ERAD, ensuring protein quality control . Unlike MNS4 (a membrane-associated protein), MNS5 operates in the ER lumen and displays unique substrate preferences .
Table 1: Key Molecular Features of MNS5
| Property | Detail |
|---|---|
| Gene ID | AT1G27520 (Arabidopsis thaliana) |
| Protein Class | Class I α-1,2-mannosidase (GH47 family) |
| Localization | Endoplasmic reticulum lumen |
| Structure | 574 amino acids with a signal peptide, lacking transmembrane domain |
| Enzymatic Activity | Trims terminal α1,2-mannose residues on N-glycans |
| Substrates | Misfolded glycoproteins (e.g., BRI1 mutants in brassinosteroid signaling) |
Role in ERAD and Plant Growth
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ERAD Regulation: MNS5 demannosylates glycoproteins to generate α1,6-linked mannose residues, marking substrates for ERAD .
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Suppression of Mutant Phenotypes:
Table 2: Phenotypic Effects of MNS5 Mutants
| Mutant | Phenotype | Mechanism |
|---|---|---|
| sbi3 | Suppressed dwarfism in bri1-5, bri1-9, and bri1-235 mutants | Stabilizes ERAD substrates via impaired demannosylation |
| mns5-1 | Reduced salt and tunicamycin tolerance | Compromised ER stress response |
| mns4-1 mns5-1 | Enhanced suppression of bri1 mutants compared to single mutants | Functional redundancy with MNS4 |
Antibody Development and Applications
While the provided sources do not detail specific commercial MNS5 antibodies, their utility in research includes:
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Protein Localization: Confirming ER localization via immunofluorescence .
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Expression Analysis: Detecting MNS5 levels in genetic mutants (e.g., sbi3 shows unchanged mRNA but altered protein activity) .
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Substrate Interaction Studies: Mapping MNS5’s role in glycoprotein processing using immunoprecipitation .
Research Implications
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Non-Redundant Function: Unlike MNS4, MNS5 exhibits unique roles in ERAD, as shown by sbi3’s specific suppression of BRI1 mutants without compensatory MNS4 upregulation .
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Biotechnological Potential: Modulating MNS5 activity could enhance crop stress tolerance by fine-tuning ERAD efficiency .
Future Directions
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Structural Studies: Resolving MNS5’s 3D architecture to elucidate substrate-binding mechanisms.
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Antibody Validation: Developing isoform-specific antibodies to distinguish MNS5 from homologous enzymes.
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
