As part of my research work, I have to perform some gene expression studies with animal tissues. I wish to know whether we can preserve the tissues at ultra low temperatures without RNA later for performing Gene expression studies.
1. you can snap freaze the tissue in liquid nitrogen and store the sample in -70 c, the time delay between harvesting and freezing will affect the RNA quality, RNA quality will depend on the tissue type.
2. Cut the tissues into small pieces ans add directly to trizol, this may then be stored in -70
Yes, you may immediately snap frozen the tissue in liquid nitrogen after harvest and stored in -80 freezer for relatively long period of time without loss of much quality of RNA. If you want to process the tissue within a couple of weeks, you can just put the tissue pieces in RNAlater in 4 degree C or -20C