RNA Extraction

RNA Extraction

What method do you use to extract RNA?
We extract total RNA from a wide range of sample types and quantities using a range of commercially available kits. We also have several liquid-handling robots that can make short work of large sample numbers. Sample types include blood fractions, plant and animal tissue, cell pellets and cell culture medium, bacteria and formalin fixed paraffin embedded (FFPE) material. If your sample type doesn’t appear in this list, please contact us as we can probably help.

Can you extract microRNAs?
Yes. There are now several kits available which allow recovery of small RNAs including miRNAs, either separately or as part of the total population that includes larger RNAs.

Can you purify mRNA for me?
Yes. We can either extract pure poly-adenylated RNA directly from your samples or perform a post-extraction purification using a Dynabeads-based method.

Will there be residual genomic DNA in my RNA prep?
For most modern RNA extraction kits, it is claimed that no gDNA is carried over into the final RNA preparation; however, we also include optional DNAse digestion steps to be sure to remove any residual DNA. If the presence of residual gDNA is something that concerns you we can include the necessary controls in our downstream processes.

What can I send and how much of it will be needed?
Ideally you should send > 1x106 cells, 30mg human/animal tissue (a 3mm cube) or 100mg plant leaf tissue, although these are only general guidelines; we can extract from smaller or larger samples, as required.
Certain tissue types require different input amounts. Contact us for advice on your particular sample set.

How should I send samples for extraction?
RNA is far less stable than DNA, and moreover, the process of harvesting and storing tissues can result in changes in gene expression. Therefore, it is essential that samples for RNA extraction are collected and stored appropriately, so as to protect the RNA and gene expression patterns once cells are lysed.

Samples should be treated in one of the following ways:
1)    Homogenised in an appropriate lysis buffer immediately after harvesting and frozen at -70°C. Shipped on dry ice.
2)    Snap-frozen in liquid nitrogen immediately after harvesting. Shipped on dry ice.
3)    RNA can also be preserved (tissue samples only) using a proprietary stabilising reagent such as RNAlater® (Qiagen).

After harvesting, tissues are immediately submerged in RNAlater® solution which rapidly permeates the tissues to stabilise and protect cellular RNA in situ. The reagent preserves RNA for up to 7 days at room temperature or 4 weeks at 2–8 °C allowing transportation, storage, and shipping of samples without ice or dry ice. If you are interested in using RNAlater please contact us for advice.

What do I need to include with my samples?
In addition to a signed agreement and purchase order number, it is essential that the following information is provided:
•    List of samples delivered
•    Sample source (organism/tissue of origin)
•    Sample type (tissue, cell pellet etc)
•    Sample volume/weight/dimensions/cell number as appropriate
NOTE: Material which is known (or suspected) to be infectious must be labelled as such, and Source BioScience must be informed and agree to receive it in advance of sending.

What yield can I expect and how do I know if the RNA is good quality?
Yields of up to 100ug are obtainable with the RNEasy mini kit at the upper limit of sample input.
UV Absorbance ratios should be A260/280 ≥1.9.
Agilent Bioanalyzer ‘RNA Integrity Number’ (RIN) should be >8.

What is a typical turnaround time for the RNA extraction?
The turnaround time depends on the sample number. We are used to handling both small and extremely large numbers of samples (in the thousands). Please contact us for a more specific estimate.

I want RNA extracted with my favourite method. Can you do this?
Yes - just let us know what it is.

Can you extract DNA, RNA and protein from a single prep?
Yes. Several options are available for simultaneous preparations. Please contact us for more information.