Micro RNAs are small naturally occurring non-coding ribonucleic acids with sizes between 18 and 40 nucleotides (nts) that have been demonstrated to play a significant role in the regulation of gene expression. As a result, interest in smaller RNA species, such as miRNA, has increased. Here we describe the purification of total RNA, including miRNA and other small RNA molecules from fresh frozen tissue samples using Beckman Coulter’s Agencourt SPRI (Solid Phase Reverse Immobilization) magnetic bead based chemistry. Beckman’s Agencourt RNAdvance tissue extraction kits (AA32646) and Biomek automation NXP liquid handler (A31840) produced high quality miRNA and RNA using the Precellys homogenizer.
Liver tissue replicates were used to evaluate miRNA extraction efficiency. The calculated average yield prepared from the RNAdvance Tissue Kit was between 25-30 μg per 5 mg liver tissue (Table 1). The average cycle threshold (Ct) value for let-7c miRNA expression in RNA samples was 25 cycles (Figure 1).
Figure 1. Overlay of let-7c gene expression from the RNAdvance Tissue Kit