MicroRNAs: Meta-controllers of gene expression in synaptic activity emerge as genetic and diagnostic markers of human disease

University of Illinois, Department of Cell & Developmental Biology, Urbana, IL 61801, USA.
Pharmacology [?] Therapeutics (Impact Factor: 9.72). 04/2011; 130(1):26-37. DOI: 10.1016/j.pharmthera.2011.01.004
Source: PubMed


MicroRNAs are members of the non-protein-coding family of RNAs. They serve as regulators of gene expression by modulating the translation and/or stability of messenger RNA targets. The discovery of microRNAs has revolutionized the field of cell biology, and has permanently altered the prevailing view of a linear relationship between gene and protein expression. The increased complexity of gene regulation is both exciting and daunting, as emerging evidence supports a pervasive role for microRNAs in virtually every cellular process. This review briefly describes microRNA processing and formation of RNA-induced silencing complexes, with a focus on the role of RNA binding proteins in this process. We also discuss mechanisms for microRNA-mediated regulation of translation, particularly in dendritic spine formation and function, and the role of microRNAs in synaptic plasticity. We then discuss the evidence for altered microRNA function in cognitive brain disorders, and the effect of gene mutations revealed by single nucleotide polymorphism analysis on altered microRNA function and human disease. Further, we present evidence that altered microRNA expression in circulating fluids such as plasma/serum can correlate with, and serve as, novel diagnostic biomarkers of human disease.

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Available from: Julie Saugstad, Jul 10, 2014
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    • "However, it is still unclear exactly how HDACs are involved in cartilage degradation. MicroRNAs (miRNAs, miRs) have emerged as fine-tuning regulators for diverse biological processes [14] [15]. During their biogenesis, the miRNA genes are transcribed into primary miRNAs (pri-miR), which are processed by Drosha and Dicer to generate miRNA duplexes consisting of a mature and a passenger miR strand [16]. "
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    • "miR-92a, miR-92a-1 * , miR-92a-2 * , and miR-92b are all members of the miR-92 family (also known as the miR-17 family) and were all up-regulated in mouse SN following chronic alcohol exposure (Most et al., unpublished results). miR-92b is involved in synaptic signaling (Ceman and Saugstad, 2011) and may be involved in the aberrant synaptic plasticity seen after alcohol exposure. In addition, miR-369 * is affected by alcohol. "
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    • "In addition, miRNAs have a proven high chemical stability for repeated frozen-thaw cycles and long periods of storage (Chen et al., 2008) Moreover, the miRNA quantification in body fluids as disease biomarkers has been explored in different human diseases including certain types of cancers (Lawrie et al., 2008; Hu et al., 2010). Indeed, biochemical analysis of serum or plasma have been suggested as a potential and noninvasive source of biomarkers for diagnosis and monitoring of progression and treatment response for neurodegenerative disorders (Ceman and Saugstad, 2011). Here, we explore alterations at the expression level of serum miRNAs in PD patients and their potential use as disease biomarkers. "
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