Figure Legend: From: Noncoding RNAs:New Players in Chronic Pain Anesthes. 2014;121(2):409-417. doi:10.1097/ALN.0000000000000265 Figure Legend: Formation of mature microRNA (miRNA). miRNA is transcribed from the genome (DNA) via RNA polymerase II (Pol II). The resulting pri-miRNA transcript is then cleaved via the endonuclease Drosha to create a 60–70 nucleotide long pre-miRNA. This transcript is then removed from the nucleus via exportin-5 to the cytoplasm where it is cleaved by Dicer, another endonuclease. The resulting double-stranded mature miRNA is unwound by a helicase or cleaved by Ago2. The single-stranded mature miRNA then acts as the core of RNA-induced silencing complex. This complex guides the miRNA to its target sequence located within the 3’-untranslated region (3’-UTR) of the target messenger RNA (mRNA). Incomplete or complete base-pairing results in degradation of the mRNA or inhibition of translation. Date of download: 10/22/2017 Copyright © 2017 American Society of Anesthesiologists. All rights reserved.