Intracellular and Organic miRNA In Situ Detection

Abstract

The detection methods of miRNA in intracellular or organisms fall into two broad categories: indirect detection and direct analysis. The indirect measurement of the expression levels of miRNAs in cells and tissues involves cells lysis and detection by qRT-PCR, northern blotting, or microarray hybridization. The direct analysis methods are a noninvasive manner for repetitively monitoring and obtaining real-time imaging of the intracellular miRNA by using imaging analysis or in situ hybridization (ISH). Technologies for direct detection of the temporal and spatial expression sequence of specific miRNA in cells or tissues are extremely important for elucidating miRNA biology. The progress of optical imaging techniques with multimodal reporter systems holds great promise for noninvasive and real-time imaging of molecular agent expression in living cell. Recent progress in nanotechnology and imaging detection techniques leads to multifunctional nanoprobe with specific-transfection, tracing, and regulation function in intracellular miRNA detection. ISH holds great promise for visualization of the spatial localization of RNA at the tissue, cellular, and even subcellular level.Keywords Intracellular miRNA · Organic miRNA · In situ detection · Cell imaging analysis · Functional nanoprobeThe detection of intracellular miRNA is significant in the development of gene therapy and gene medicines. The deficiency of small size and degradation of the mature miRNAs make it difficult to directly transfer the specific miRNA into the cell. A noninvasive manner for repetitively monitoring and obtaining real-time imaging of the intracellular miRNA is required for the analysis of miRNAs in practical clinic application. Efficient gene vectors, including viral [1] and nonviral categories, [2] were usually required to translocate miRNA probe through membrane barrier into the cell. Retrovirus and adenovirus vectors can be effectively transferred via the gene probes (DNA, RNA) into most cell lines. However, the