Description

Actinomycin D (CAS 50-76-0), also known as Dactinomycin, is an ultra-pure polypeptide antibiotic and a widely used transcription inhibitor. It functions as a DNA intercalator, forming a stable complex with double-stranded DNA and selectively inhibiting DNA-dependent RNA synthesis.

Because it binds DNA rather than RNA, Actinomycin D is frequently used in transcription shut-off experiments, mRNA half-life assays, RNA stability studies, and strand-specific reverse transcription workflows.

Mechanism of Action

Actinomycin D intercalates into double-stranded DNA and blocks RNA polymerase progression, thereby inhibiting DNA-primed RNA synthesis. It has also been reported to interfere with the minus-strand transfer step in reverse transcriptase systems.

Importantly, since Actinomycin D binds DNA but not RNA:

It inhibits transcription from DNA templates
It does not directly block RNA-templated first-strand cDNA synthesis
It can suppress unwanted DNA-templated artifacts during RT-based workflows

This property makes it useful in directional RNA library preparation and strand-specific RT protocols.

Chemical structure: peptide

Specifications

Total Product Size	5mg
Individual Container Size	5mg
Refrigeration Requirements	Refrigerator
Shipping Conditions	ICE
UNSPSC Code	51101500
UNSPSC Category	Antibiotics and Antimycotics
CAS	[50-76-0]
Hazard Class	Class 6.1
Hazard UN	UN3462
Hazard PG	PGII
Grade	Ultra Pure
DG	No
Storage	2 to 8℃
Sterile	Yes

Application

Transcription inhibition studies
mRNA stability and half-life assays
Directional RNA library preparation
HIV replication suppression research
PC12 programmed cell death studies
Selection agent in cell culture

Actinomycin D for mRNA Half-Life Assays (qPCR-Based Time Course)

One of the most searched use cases is transcription inhibition for mRNA decay studies.

Common Experimental Setup

Researchers commonly report:

Concentration range: 0.1–5 µg/mL (cell-type dependent)
Typical time course: 2–24 hours
Sampling intervals: every 2 hours for unstable RNAs
Housekeeping control: 18S rRNA often used

However, optimal concentration depends on:

Cell type (e.g., embryonic stem cells vs differentiated cells)
Target RNA stability
Cytotoxic sensitivity

Practical Recommendations

Always optimize concentration for your cell line
Start with 0.5–2 µg/mL for mammalian cells
Use multiple housekeeping genes if RNA yield decreases significantly
Confirm inhibition efficiency at early timepoints

Handling & Storage Considerations (Frequently Asked Questions)

Is Actinomycin D light sensitive?

Yes. It is highly light-sensitive. Always wrap containers in foil.

Does it stick to plastic or glass?

Yes. In solution, it tends to adsorb to surfaces and stain materials.

Should I prepare fresh stock?

Yes. Fresh DMSO stocks are recommended.

Is it stable?

Stable 15+ months at 2–8°C if protected from light and moisture
Diluted solutions degrade rapidly
Frozen concentrated aliquots stable ~1 month

Documents

COA

SDS

Disclaimer: For laboratory research use only.