"missing" RNA

[Klaus Salger]

Karen Ferri (kferri at email.unc.edu) wrote:

<snip>
: Homogenized some tissue, isolated and purified the RNA, checked OD's, and 
: ran on a gel to check RNA integrity.  For 1 sample, the gel lane was 
: blank (not even smeared, which would indicate denaturation).  I ran 3 
: gels to be sure the problem of possible RNA omission to gel lane was 
: addressed.  Still no run, even after adding extra RNA to lane.  The [] of 
: the sample (I checked it twice) was 17% lower the second time, but acc. 
: to my boss, still not low enough to not show up.
<snip>

Karen,
I think there's no RNA in this particular sample (or very few). I guess
you determined the [RNA] spectorphotometrically. Did you get a 260/280nm
ratio of about 1,7? Even if you did - getting a visible pellet and having
absorption at 260nm doesn't necessarily mean that this is RNA. As far as
I know at least the pellet may well consist of carbohydrates.
If I don't see anything on the gel I asume that there is no RNA in it.

Cheers
  Klaus

--
Klaus Salger                phone : ++49 (0)89 5902 -502
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