Northern sensitivity

Sun Mar 14 02:46:23 EST 1993

Blair Jennings at <HF.BXX at>:
>I'm trying to find out what is the lowest concentration of message
>which can be seen on a Northern blot. Also how much more sensitive
>is the RNase protection assay or is it? I want to know this because
>I'm looking at a constitively expressed message during early
>gestation and am having a hard time seeing anything other than my
>positive control.

I don't know if you're using total RNA for gel running but it may be helpful
if you load poly-A RNA instead. Now if the transcripts you wish to
detect are indeed rare at the cell stage your looking, you may find it
worthwhile to do reverse PCR. Try looking up the ff. paper:

S.A. Fuqua et al. (1990) A simple polymerase chain reaction method for
detection and cloning of low abundance transcripts. BioTechniques 9(2):

Hope I imparted something that will be useful for you Blair. ;-)
IRRI, Philippines
e-mail:  rscott at

More information about the Methods mailing list