siRNA is a synthetic double-stranded RNA duplex. You transfect it directly into cells. It silences the target mRNA for 3 to 7 days before diluting with cell division. shRNA is a DNA-encoded hairpin. It is transcribed endogenously from a U6 or H1 promoter. Dicer processes it into siRNA-like duplexes. It provides sustained knockdown when delivered via a stable lentiviral vector. Use siRNA for speed. Use shRNA for stable, long-term silencing.
Cloning & Expression Systems
RNA Interference & Small RNAs
siRNA and shRNA gene silencing reagents for reversible, sequence-specific knockdown
Each format targets messenger RNA post-transcriptionally, so your knockdown is reversible and leaves the genome sequence untouched. Your options span four format families: synthetic siRNA and lentiviral siRNA vector sets for transient or stable RNA interference, shRNA expression constructs and linearised vectors for stable chromosomal integration, microRNA overexpression and knockdown constructs for miRNA pathway studies, and custom shRNA cloning services for targets outside the catalogue.
Pre-designed siRNA gene silencing reagents cover thousands of gene-specific targets in human, mouse, and rat. They are available as lentiviral delivery formats for use in your hard-to-transfect cells. Linearised shRNA expression vectors are ready for your custom hairpin insertion, including full inducible Tet-On/Off shRNA backbone libraries.
The microRNA arm of the catalogue provides pre-microRNA expression constructs for your overexpression and knockdown. These cover a broad range of human miRNA targets.
Choose format by duration, then by delivery requirement.
- Duration: transient (3 to 7 days). Synthetic siRNA oligos delivered by lipofection suit this timeframe. This method is fast, needs no cloning, and lets you titrate dose freely.
- Duration: stable (weeks to months). Use lentiviral siRNA or shRNA constructs. Tet-inducible variants add doxycycline control for your experiments where constitutive knockdown is toxic.
- Target: mRNA coding sequence. siRNA or shRNA targeting the CDS gives you maximum knockdown efficiency. Lentivector sets cover CDS positions across human, mouse, and rat transcriptomes.
- Target: microRNA pathway. Pre-microRNA overexpression constructs or anti-miR knockdown vectors suit this target. The matching inhibitor construct supports your concurrent pathway validation.
- Delivery: hard-to-transfect cells (primary, suspension). Choose lentiviral delivery via siRNA or shRNA virus. siRNA AAV vector options are available as well, together with AAV-packaged scrambled siRNA controls in multiple serotypes.
- Custom target not in catalogue. Order custom lentiviral shRNA cloning for your single or dual hairpin designs targeting sequences outside the pre-designed range.
Applications
Target validation and pathway analysis
siRNA transfection gives rapid, dose-titratable knockdown, supporting fast validation of your target before committing to a stable lentiviral knockdown model.
Stable knockdown in primary cells and in vivo
Lentiviral shRNA delivers stable, heritable silencing in your hard-to-transfect primary cells, including T cells, supporting long-term studies.
microRNA biology
Pre-microRNA overexpression and anti-miR knockdown vectors allow gain- and loss-of-function study of your endogenous microRNA pathways, including 3'UTR regulation.
Combinatorial and dose-response knockdown studies
Titrate synthetic siRNA dose to generate your partial knockdown series, defining gene dosage effects a full knockout would mask.
Orthogonal validation of CRISPR knockout phenotypes
Confirm your CRISPR knockout phenotype with an independent siRNA or shRNA knockdown at a non-overlapping sequence, reducing off-target risk.
Product Catalog
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shRNA Libraries & Constructs
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shRNA Target Gene Sets
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siRNA 27mer Oligo Duplexes
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siRNA Constructs
GeneCopoeia siRNA Constructs in Lentiviral & AAV Vectors for Efficient, Stable Gene Knockdown
microRNA Quantification by qRT-PCR
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microRNA Overexpression & Knockdown Constructs
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Frequently asked questions
Use at least two independent siRNA sequences targeting different regions of the same mRNA. Confirm that both produce the same phenotype. Verify knockdown at the mRNA level by RT-qPCR. Verify it at the protein level by Western blot. Include a non-targeting scrambled control sequence. Where possible, rescue the phenotype by re-expressing an siRNA-resistant cDNA construct.
Include a non-targeting negative control with a scrambled or non-homologous sequence. Include a positive control targeting a constitutively expressed essential gene to confirm transfection and knockdown efficiency. Include a mock-transfected sample to separate knockdown effects from transfection reagent toxicity. For lentiviral shRNA experiments, include a non-targeting shRNA lentiviral construct at the same MOI.
Product catalogs
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