Background: A synapse is a fundamental signaling component that facilitates neuronal connectivity and information processing in the brain. Dynamic changes in the number, size, and functionality of synapse are induced by extensive signaling networks and structural proteins, which are stimulated on various neuronal activities. Changes in the expression level of synaptic proteins depend upon the physiological and pathological conditions at transcriptional, post-transcriptional, and post-translational levels. MicroRNAs (miRNAs) have not only emerged as pivotal gene expression regulators in neurons, but also in diverse cell types. miRNAs are evolutionarily conserved small non-coding RNAs that modulate mRNA stability and protein synthesis by interacting with 3'-untranslated region (3'-UTR) of mRNAs. Often, miRNA expression is limited to specific neuronal compartments such as axons, dendrites, and cell body to locally regulate protein synthesis in response to various stimuli.
Objective: Increasing evidences suggest that miRNAs are involved in the regulation of neuronal proliferation, differentiation, migration, development, and many other processes. This article reviews recent findings on the role of miRNAs in synapse formation and function.
Conclusions: Many studies have elucidated the role of miRNAs in diverse neuronal physiological and pathological processes. A better understanding of the mechanisms involved in miRNA functioning at the synapse will be beneficial in formulating novel therapeutic strategies.
Keywords: Axon; Dendritic spine; Gene expression; MicroRNA; Synapse.