DCL3 Antibody
Description
Introduction to DCL3 Antibody
The DCL3 (Dicer-like 3) antibody is a specialized tool used to study the function and expression of the DCL3 protein, a ribonuclease III enzyme critical in RNA interference (RNAi) pathways. DCL3 generates 24-nucleotide (nt) small interfering RNAs (siRNAs) that regulate transcriptional gene silencing, heterochromatin formation, and antiviral defense in plants . This antibody enables researchers to investigate DCL3’s role in epigenetic regulation, genome stability, and pathogen resistance.
Molecular Mechanism of DCL3
DCL3 processes double-stranded RNA (dsRNA) into 24-nt siRNAs through distinct biochemical steps:
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Substrate Recognition: Prefers dsRNA with 5′-phosphorylated adenosine/uridine and 1–2 nucleotide 3′ overhangs .
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Catalytic Activity: Cleaves dsRNA into 24-nt duplexes with 2-nt 3′ overhangs via a 5′ counting rule (measuring from the phosphorylated end) .
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Functional Redundancy: Works alongside DCL2 and DCL4 in antiviral immunity but specializes in repeat-associated siRNA production .
Substrate Specificity
DCL3 exhibits unique enzymatic preferences compared to other Dicer-like proteins:
Antiviral Defense
DCL3-produced 24-nt siRNAs mediate RNA-directed DNA methylation (RdDM) to silence viral genomes, particularly against DNA viruses . For example:
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In Arabidopsis, DCL3-deficient plants show increased susceptibility to Cauliflower mosaic virus due to impaired RdDM .
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DCL3 collaborates with RNA-dependent RNA polymerase 2 (RDR2) to amplify antiviral siRNAs .
Epigenetic Regulation
DCL3-generated siRNAs target transposons and repetitive DNA elements, maintaining genome stability via heterochromatin formation . Studies in Brassica species demonstrate conserved roles in silencing retrotransposons .
Cross-Reactivity and Specificity
The DCL3 antibody (e.g., PhytoAB PHY1173S) has been validated in multiple species:
| Antibody ID | Reactivity |
|---|---|
| PHY1172S | Arabidopsis thaliana |
| PHY1173S | A. thaliana, Brassica rapa, B. napus |
| PHY3902S | A. thaliana (tissue-specific isoforms) |
| Source: Product specifications and cross-reactivity assays . |
Applications in Research
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Western Blot: Detects ~220 kDa DCL3 protein in plant extracts .
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Immunoprecipitation: Isolates DCL3 complexes for functional studies .
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Localization Studies: Visualizes nuclear and cytoplasmic DCL3 pools in response to viral infection .
Challenges and Future Directions
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
- Research indicates that variations in a host plant's nutrient status affect the post-translational regulation of DCL3 and DCL4 dicing activities. Phosphate deficiency inhibits DCL3 activity, while inorganic phosphate directly activates it. PMID: 28069892
- This expression-dependent RdDM mechanism operates through RNAi degradation of transposable element mRNAs into small RNAs guided by the RNA-dependent RNA polymerase 6 (RDR6) protein, hence being termed RDR6-RdDM. A novel mechanism of expression-dependent RdDM, termed DCL3-RdDM, has been identified. This mechanism functions through DICER-LIKE3 (DCL3) but bypasses the requirement for both RNA polymerase IV and RDR6. PMID: 27506905
- Researchers identified Pol IV and RDR2-dependent RNAs (P4R2 RNAs) that accumulate in dcl3 mutants. These RNAs are diced into 24 nt RNAs by DCL3 in vitro. PMID: 26430765
- CMA33/XCT modulates small RNA production by regulating the transcription of Dicer-Like genes. PMID: 25770820
- DCL3 preferentially cleaves short double-stranded RNAs with 5' phosphorylated adenosine or uridine and a 1 nt 3' overhang. PMID: 24214956
- The data suggest a mechanism whereby IBM1 regulates a series of protein-coding genes, including DCL3, through the RdDM-dependent control of siRNA biogenesis. PMID: 22772985
- DNA methylation establishment and maintenance defects present in sr45-1 mutants are enhanced in the dcl3-1 mutant background, suggesting a synergistic cooperation between SR45 and DICER-LIKE3 (DCL3) in the RdDM pathway. PMID: 22274613
- Research shows that small interfering RNAs and larger RNA fragments corresponding to miRNA target genes accumulate in wild-type plants but not in ago1, the RNA-dependent RNA polymerase mutants rdr2 and rdr6, or the Dicer-like mutants dcl1 and dcl3. PMID: 16798886
- DICER-LIKE 1 and DICER-LIKE 3 are involved in the generation of small RNAs; mutants exhibit a delay in flowering. PMID: 17579240
- DCL3 is essential for the reception of long-distance mRNA silencing. PMID: 17785412
