A Simple Alternative to Stereotactic Injection for Brain Specific Knockdown of miRNA

Abstract

MicroRNAs (miRNAs) are key regulators of gene expression. In the brain, vital processes like neurodevelopment and neuronal functions depend on the correct expression of microRNAs. Perturbation of microRNAs in the brain can be used to model neurodegenerative diseases by modulating neuronal cell death. Currently, stereotactic injection is used to deliver miRNA knockdown agents to specific location in the brain. Here, we discuss strategies to design antagomirs against miRNA with locked nucleotide modifications (LNA). Subsequently describe a method for brain specific delivery of antagomirs, uniformly across different regions of the brain. This method is simple and widely applicable since it overcomes the surgery, associated injury and limitation of local delivery in stereotactic injections. We prepared a complex of neurotropic, cellpenetrating peptide Rabies Virus Glycoprotein (RVG) with antagomir against miRNA-29 and injected through tail vein, to specifically deliver in the brain. The antagomir design incorporated features that allow specific targeting of the miRNA and formation of non-covalent complexes with the peptide. The knock-down of the miRNA in neuronal cells, resulted in apoptotic cell death and associated behavioural defects. Thus, the method can be used for acute models of neuro-degeneration through the perturbation of miRNAs. Video LinkThe video component of this article can be found at

MicroRNA mediators of early life stress vulnerability to depression and suicidal behavior

“…Several groups have used lentiviral injection to selectively augment and reduce individual miRNAs in living rodent brain [85,122], including one ELS study [54]. Knockout mice have also been used extensively to study the importance of specific (and clusters of) miRNAs [123] and more recent technological advances propose non-invasive means of delivering brain-specific antagomirs to study miRNA knockdown [124]. In combination with genomewide expression and in-vitro studies, these techniques can help us to elucidate the importance of miRNAs in stress susceptibility.…”

Differential Expression Analysis of microRNA in the Central Nervous System of Mouse Infected with Rabies Virus

“…miRNAs are endogenous, small, single-strand, non-coding RNA that contain 18-23 nucleotides and are crucial post-transcriptional regulators of gene expression (Xiao and Rajewsky 2009). To date, a number of 18-30 nt small RNAs have been identified as a crucial regulatory molecules in unicellular and multicellular organisms, and animal viruses (Ambros, 2004;Griffiths-Jones et al, 2008;Suryawanshi et al, 2015;Miskinyte et al, 2017;Yang et al, 2017).…”