Universal

Products - Amplify & Label - Reference mRNAs

Universal Reference Human mRNA is a proprietary blend of amplified high-quality mRNA purified from a diverse set of human, mouse or rat tissues. This reference mRNA provides a common denominator for accurate and reproducible comparisons of gene expression data. Pooled reference mRNA can be used for multicolor hybridization experiments using DNA microarrays. The signal generated from this mRNA will ease the normalization process, in both intensity-based and reference-channel-based normalization. The use of pooled reference RNA has been shown to reduce inter and intra-laboratory variations of microarray data. This product is compatible with all commercially available microarray labeling systems as well as other research applications such as RT-PCR, and QRT-PCR that demand high quality reference pool of mRNA.

Can be used stand alone or in conjunction with:

Uses include:

Normalization standard for two-color microarray systems
Standardization method for single color microarray systems
Real-time PCR amplification efficiency and standardization studies

ArrayIt Universal Reference mRNA:

Provides more broad gene representation over competing products
Is available for three different species: Human, Mouse, and Rat
Guaranteed high purity mRNA, free of contamination
Bulk production minimizes lot-to-lot variation
Highly useful for any DNA based array, microarray or PCR platform

Packaging:

30 µg mRNA in a 0.5 ml micro-centrifuge tube, concentration 1µg/µ

Storage:

Store at –80° C stable for 6 months at this temperature.
It is advisable to minimize handling and repeated freeze-thaw of this product; we recommend that at the time of first use the product be split into smaller, single use size aliquots, using RNAse free tips and storage vials.

Differences between using total RNA and mRNA in labeling for microarrays are as follows:

1. When labeling using total RNA in either direct or in-direct methods, oligo dT to prime the RT reaction is used. Therefore the labeling is limited to the capability of the reverse transcriptase to generate large fragments on a single run. On the other hand, when using mRNA, a mixture of oligo dT and random primers is used, allowing a much better cDNA:dye ratio and much better labeling. For this reason, many microarray users prefer to purify mRNA prior to reverse transcription and labeling.

2. The use of reference mRNA becomes absolutely necessary and saves a lot of time and money, when a user is working from small quantities of RNA and is performing mRNA amplification for microarray studies. The amplified mRNA from the samples can be used directly with the reference mRNA, saving one round of amplification. Since, the sample total RNA (purified by the user) and the reference total RNA (purified by the vendor) will have different purity, the results will vary in the amplification reaction as well.

Number of labeling per pack of 30 µg

For direct labeling use 2-3 µg/reaction, for indirect labeling use 1-2 µg/reaction.

Figure 1. Quality testing of Human Universal mRNA

Step 1. Two equal aliquots (2.5 µg) of Human universal mRNA was labeled with Cy3 and Cy5 labeled dCTP (Amersham) each using reverse transcriptase and anchored oligo dT primer and random nanomer.
Step 2. After separating the bound and free dye the labeled cDNAs were mixed and hybridized to a cDNA microarray containing 9200 human ESTs
Step 3. After washing the microarray was scanned using an Axon scanner
Step 4. The scanned image was gridded with Axon Genepix software the results were subjected to the following analysis: Step 1A. The median value of (intensity – background) was taken and filtered using the criteria that Signal > Background + 2x SD of Background Step 2A. Those spots whose signal value was less than 100 in either of the channels were removed. Step 3A. After all these filtering 8120 spots or 88 % of the spots gave good results Step 4A. When a correlation graph was plotted for Red: Green channel values the correlation coefficient was 0.9796

Ordering Information

Product

Description

Amount

Catalog ID

Price (US Dollars)

ArrayIt® Human Universal Reference mRNA

A proprietary blend of amplified high-quality mRNA purified from a diverse set of human tissues.

30 µg of mRNA

URH

$467.50

ArrayIt® Mouse Universal Reference mRNA

A proprietary blend of amplified high-quality mRNA purified from a diverse set of mouse tissues.

30 µg of mRNA

URM

$467.50

ArrayIt® Rat Universal Reference mRNA

A proprietary blend of amplified high-quality mRNA purified from a diverse set of rat tissues.

30 µg of mRNA

URR

$467.50

Discounts
1-5 packages = list price ($425 per package)
6-10 packages = 10% discount ($382.50 per package)
10-20 packages = 15% discount ($361.25 per package)
>20 packages = 20% discount ($340.00 per package)

To order ArrayIt® Brand Products: call 408-744-1331, fax 408-744-1711, email arrayit@arrayit.com or click on the button below to proceed directly to the purchase page.

*International pricing may vary as much as 30% (or more depending on country) due to import duties, stocking fees and technical support.

Warranty
TeleChem's ArrayIt® Universal mRNA products are sold for research purposes only. TeleChem's products are not for use in human diagnostics or for drug purposes, nor are they to be administered to humans in any way. Extreme care and exact attention should be practiced in the use of the materials described herein. All TeleChem products are subject to extensive quality control and are guaranteed to perform as described when used properly. This product is stable for at least 1 year from the date of purchase when stored at –80°C. Any problems with these products should be reported to TeleChem immediately. Our liability is limited to the replacement of the product, or a full refund. Any misuse of this product is the full responsibility of the user, and TeleChem makes no warranty or guarantee under such circumstances.