RNA isolation from frozen cells - (Aug/22/2011 )

Hi, I was wondering if there is any drawback to isolating RNA from cells frozen in -80 for a month. I had treated cells with a compound, collected the pellet, rinsed with PBS and stored the cells at -80...it's been a month and I would like to extract RNA for gene expression analysis from these cells. Will storing my cells for a month affect my RNA isolation and gene expression results? Just curious since I really don't want to retreat my cells with the compound.

Thanks.

I often isolate total RNA from cells very successfully. The way I do this would take exactly the same amount of time that you spent in rinsing and freezing your cells, but would result in beautifully intact RNA. I fear that RNA from cells stored as you described would be severely compromised by degradation.
Next time: after treating your cells, rinse well with PBS, aspirate, add 1 mL of Trizol (for a T25 flask), scrape dissolved cells up and put in a tube, then freeze. The Trizol will protect the RNA from degradation, and can be stored at -80 for years with no apparent ill effects.

Storing cells frozen on -80 is not good for RNA isolation. They need to be snap frozen and stored in liquid nitrogen or lysed with Trizol and stored in it at -80.