DNA ladders on a northern blot - (Sep/19/2009 )

Hi all,

I was wondering if someone could tell me if this would work;

Run my total RNA sample (looking for miRNA) with a DNA ladder on a denaturing gel.
The reason I want to use a DNA ladder is that I can label it with dye and image it and my labeled probe in the Odyssey (thus avoiding the isotope issue)

My question are:
- Will the denaturing gel denature the dsDNA ladder, or do I have to heat it, then put on ice prior to adding to the gel?
- Will the DNA ladder run at the same rate (in relation to size) as my RNA?

Thanks for the help!

The answers are:
Yes it will denature and no respectively. You can buy RNA ladders for Northerns - Roche sells some, DNA ladders will not work well other than to tell you that you have run you gel evenly.