I am trying to extract RNA from mice ears and for some reason I don't have RNA when I perform the electrophoresis. I directly cut the ears and I put it in a tube with a bead and trizol. then I place it on ice and I use a mash machine for tissue lysis for 8 minutes and 4 ºC. After that, I perform RNA isolation according with a protocol using chloroform, isopropanol and ethanol.
I think the problem could be the extraction. Do you have any suggestions?