title: A non-canonical landscape of the microRNA system.
abstract: Microribonucleic acids, best known as microRNAs or miRNAs, are small, non-coding RNAs with important regulatory roles in eukaryotic cells. Here, I present a broad review on highly relevant but generally non-depicted features of miRNAs, among which stand out the non-conventional miRNA seed sites, the unusual messenger RNA (mRNA) target regions, the non-canonical miRNA-guided mechanisms of gene expression regulation, and the recently identified new class of miRNA ligands. Furthermore, I address the miRNA uncommon genomic location, transcription, and subcellular localization. Altogether, these unusual features and roles place the miRNA system as a very diverse, complex, and intriguing biological mechanism.
authors.affiliation: Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná Curitiba, Brazil.
authors.forename: Gabriel A
authors.initials: GA
authors.lastname: Cipolla
keywords: 5′UTR; RNA activation; coding sequence; miRNA; miRNA*; non-canonical; subcellular localization; transcriptional silencing