MicroRNAs in neurodegenerative disorders.

MicroRNAs (miRNAs) are endogenous, small, noncoding RNAs regulating eukaryotic gene expression at the post-transcriptional level. During the last decade, considerable advances have been made in our understanding the biogenesis of miRNAs, the molecular mechanisms by which they regulate gene expression and their functional role in various physiological situations. miRNAs are abundant in the brain where they have crucial roles in development and synaptic plasticity. Accumulating evidence from postmortem brain analyses and animal model studies has begun to suggest that miRNA dysfunction contributes to neurodegenerative disorders. Here, we discuss several examples of investigations demonstrating the role of miRNAs in neurodegenerative disorders. As the expression of disease-causing genes is regulated by certain miRNA(s), changes in these miRNAs could lead to the accumulation of disease-causing proteins, and subsequently to neuronal dysfunction and death. Detailed understanding of these mechanisms can provide potential new therapeutic approaches to slow down or halt the progression of neurodegenerative diseases.