RNA Isolation

Fresh tissue was immediately frozen into liquid N2. About 20-25 mg of frozen tissue was homogenized in cold RTL buffer containing b- mercaptoethanol (RNeasy Mini Kit, Qiagen) with glass hand tissue homogenizer. Subsequently the RNA was purified with the RNeasy Mini Kit (Qiagen). During the isolation process the DNA was removed by on-column DNase I. RNA concentration was measure with spectrophotometer and the quality was determined with Bio-analyzer ( Agilent Technologies)