microRNA (miRNA) are small RNAs that direct enzyme complexes to degrade messenger RNA molecules and thus decrease their activity by preventing translation.

Small interfering RNA (siRNA) is a class of double-stranded RNA molecules, 20-25 base pairs in length. They interfere with the expression of specific genes with complementary nucleotide sequences by degrading mRNA after transcription, preventing translation. It silences the specific gene expression.

Transfection is the process of introducing nucleic acids (genes) into eukaryotic cells. The result may be to overexpress certain proteins, to correct a genetic defect, or to create a reporter cell that conveniently fluoresces when triggered by an agonist.

Purified, full-length RNA is required for cDNA cloning. It is also used in some methods for analyzing gene expression and for microarrays utilizing cDNA. RNA is prepared from bacteria, tissue culture cells, tissues and plants. Preparations can be purified messenger (mRNA) or total RNA that includes mRNA, ribosomal (rRNA) and transfer RNA (tRNA). The scale….