Peripheral Signatures of Psychiatric Disorders: MicroRNAs

Abstract

MicroRNAs (miRNAs) are 22 nucleotide long RNA transcripts, their synthesis starts in nucleus and continues in cytoplasm. As being critical for post-transcriptional regulators of gene expression they have been investigated in psychiatric disorders. There are numerous studies performed in peripheral tissues for psychiatric disorders. Here in this article, we aimed to review some common miRNAs denoted significant in at least two studies and their relevance to psychiatric research. We focused on miR-320, miR-106, miR-34, miR-223, miR-107, and miR-134.

Keywords: Biomarker.; Blood; MicroRNA; Plasma; Psychiatry; Serum.

Fig. 1

The synthesis of microRNAs (miRNAs) starts in the nucleus. RNA polymerase II synthesizes primiRNAs with 5′ cap and 3′ polyA tail. Drosha and its co-factor DiGeorge syndrome critical region protein 8 (DGCR8) remove 5′ cap and 3′ polyA tail and form premiRNAs. PremiRNAs are transported by exportin 5/Ran GTP system.

Fig. 2

The maturation of microRNAs (miRNAs) in the cytoplasm. Dicer and its co-factor trans-activator RNA binding protein (TRBP) perform cleavage. Mature miRNAs incorporate to RNA-induced silencing complex (RISC). miRNAs usually point mRNAs 1) to degrade or 2) prevents them from translation. In rare cases miRNAs may 3) increase gene expression.