Description(s):
miR-21 is overexpressed in a wide variety of cancers. It is believed to be an oncogene by downregulating the expression of many tumor suppressors, including programmed cell death 4 (PDCD4), tumor suppressor Pdcd4, the PTEN tumor suppressor gene, and the tumor suppressor gene tropomyosin 1 (TPM1). miR-21 is also found to be an important regulator of cancer-cell survival. Different from the survival pathway mediated by IL-6/Stat3 activation through the expression of antiapoptotic proteins, miR-21 is upregulated by Stat3, which mediates the suppression of apoptosis possibly through the inhibition of TPM1 and/or other proteins. Signosis’ miR-21 plate assay kit provides a simple and quick method to analyze this miRNA molecule.
Principle
In the proprietary miRNA plate assay, one miRNA molecule is flanked by a capture oligo and a biotinated detection oligo through two bridges oligos. One of the bridge oligos is partially hybridized with the miRNA molecule and the capture oligo and another with the miRNA and the detection oligo. The hybrid is immobilized onto plate through hybridization with an immobilized oligo and detected by a streptavidin-HRP conjugate and chemiluminecscent substrate. This hybrid structure is sensitive to the sequence of the miRNA molecule. One nucleotide difference will prevent the formation of the hybrid and therefore miRNA isoform can be differentiated, which normally is hard to tackle with Northern blot. In addition, the sensitivity of the assay is higher than miRNA Northern blot assay..gif)
Data
miRNA plate analysis of miR-21 expression. A: expression of miR-21in human ovary, kidney, and HeLa was analyzed with miR-21 Northern blot (top) and miR-21 plate assay (bottom). B: miR-21 was analyzed with dilutions of HeLa total RNA.
