MicroRNAs in Development and Disease

Abstract

LSayed D, Abdellatif M. MicroRNAs in Development and Disease. Physiol Rev 91: 827-887, 2011; doi:10.1152/physrev.00006.2010 are a class of posttranscriptional regulators that have recently introduced an additional level of intricacy to our understanding of gene regulation. There are currently over 10,000 miRNAs that have been identified in a range of species including metazoa, mycetozoa, viridiplantae, and viruses, of which 940, to date, are found in humans. It is estimated that more than 60% of human protein-coding genes harbor miRNA target sites in their 3= untranslated region and, thus, are potentially regulated by these molecules in health and disease. This review will first briefly describe the discovery, structure, and mode of function of miRNAs in mammalian cells, before elaborating on their roles and significance during development and pathogenesis in the various mammalian organs, while attempting to reconcile their functions with our existing knowledge of their targets. Finally, we will summarize some of the advances made in utilizing miRNAs in therapeutics.

Circulating Serum Exosomal miRNAs As Potential Biomarkers for Esophageal Adenocarcinoma

“…MicroRNAs (miRNAs) are small non-coding 21-23 nucleotide RNA molecules, which regulate the production of proteins from mRNA [5,6]. They are found in the cell free fraction of blood, including serum, and can be reliably measured from frozen stored samples [7].…”

miR-128 represses L1 retrotransposition by binding directly to L1 RNA

“…More than 60% of the human transcriptome has been predicted to be under miR regulation, thus making this post-transcriptional control pathway as important as protein pathways in the regulation of cell functions 2 . It is clear that miRs have essential roles in regulating diverse functions in normal and diseased cells 8,9 .L1 belongs to the most abundant class of autonomous transposable elements 10 . Human L1 contains two open reading frames, ORF1 and ORF2, which encode a protein with RNA-binding and nucleotide acid-chaperone activity (ORF1) 11 and a protein with endonuclease and reverse-transcriptase activities (ORF2) 12-15 , respectively.…”

“…More than 60% of the human transcriptome has been predicted to be under miR regulation, thus making this post-transcriptional control pathway as important as protein pathways in the regulation of cell functions 2 . It is clear that miRs have essential roles in regulating diverse functions in normal and diseased cells 8,9 .…”

HIV-1 RRE RNA acts as an RNA silencing suppressor by competing with TRBP-bound siRNAs

“…Since their identification, micro (mi)RNAs encoded by the cell have been shown to regulate various cellular pathways, including development, immune responses, inflammation and cell growth. 1 In mammals, miRNAs are transcribed in the nucleus as primary-miRNAs, which are processed by Drosha and DGCR8 into precursor (pre-) miRNAs. 2 Pre-miRNAs are then exported into the cytoplasm via an exportin-5 mediated pathway, where they are bound by Dicer and the TAR-RNA-Binding Protein (TRBP).…”