Endocytosis and intracellular RNAs imaging of nanomaterials-based fluorescence probes.

Recently, using nanomaterials to enhance the endocytosis capability and sensitivity of probes for RNA imaging in living cells has gotten the attention of many researchers. Nanomaterials, as a reliable alternative to transfection reagents, could prevent nucleic acid probes from being degraded by DNase, and bring them into sub-cellular locations for efficient internalization. Therefore, nanomaterial-based fluorescent probes (NFPs) provide a promising sensing platform to realize in situ RNA detection and imaging, which can reveal the expression of RNA at single cell level and provide large amount of information about RNA spatial localization. Meanwhile, many RNAs are in low abundance in living cells, resulting in difficulty in sensitive detection. Thus, the incorporation of NFPs and signal amplification strategy offers a broader prospect for the detection of RNAs, that have been proven as predominant therapeutic targets or diagnostic biomarkers. Herein, the purpose of our review is to first introduce the general procedure of NFPs used for in situ RNA imaging and how nanomaterials deliver these probes into living cells. Further, we focused on different kinds of nanomaterials that are mainly used for sensitive detection of RNAs and those in low abundance, through different signal read-out modes. Nanomaterial-based fluorescent probe (NFP) provides a promising sensing platform to realize effectively cellular endocytosis and intracellular RNA Imaging in situ. In our review, we try to basically introduce the whole progress of NFPs used for in situ RNA imaging, particularly focusing on the endocytic pathways that nanomaterials deliver these probes into living cells, as well as different kinds of nanomaterials that are mainly used for sensitive signal detection of RNAs, especially for those in low abundance. [Display omitted] • Monitoring the level of RNA expression, can assist our understanding of the progression, diagnosis and further treatment of tumor. • NFPs has high internalization efficiency and excellent biocompatibility to achieve cellular uptake and RNA imaging in situ. • Different kinds of nanomaterials for detection of RNAs, especially for those in low abundance, are summarized. [ABSTRACT FROM AUTHOR]