Author: Rodney E. Shackelford, D.O., Ph.D. (see Reviewers page)
Revised: 14 April 2012, last major update April 2012
Copyright: (c) 2008-2012, PathologyOutlines.com, Inc.
● RNA is less stable than DNA, making its purification more difficult
● 4M guanidinium thiocynate or phenol with SDS are often used to denature RNases naturally present in blood, plasma, body fluids, bacteria, fungi, plants
● Must avoid sample contamination with RNases, which are extremely ubiquitous in environment
● Must use extremely clean reagents, such as diethylpyrocarbonate-treated water
● Must keep samples cold to lower RNase activity; isolate pure RNA quickly and efficiently to minimize RNase exposure, and avoid a basic pH in all extraction and storage solutions, as RNA rapidly degrades under basic conditions
Poly (A)+ RNA Purification
● mRNA represents only 1-2% of total cellular RNA, but is often analyzed for research and molecular diagnostic purposes
● Most eukaryotic mRNAs carry poly (A)+ 3’ terminal tails, which can be used to isolate mRNA over an oligo (poly-dT) attached to a solid matrix
● Under the right buffer conditions, cellular mRNA poly (A)+ tails will form RNA-DNA hybrids; the solid phase can then be washed to remove unwanted cellular continents and a later denaturing wash can be employed to remove pure mRNA
End of Molecular Pathology > DNA Purification > RNA Purification
This information is intended for physicians and related personnel, who understand that medical information is often imperfect, and must be interpreted in the context of a patient's clinical data using reasonable medical judgment. This website should not be used as a substitute for the advice of a licensed physician.
All information on this website is protected by copyright of PathologyOutlines.com, Inc. Information from third parties may also be protected by copyright. Please contact us at [email protected] with any questions (click here for other contact information).