miRNA strand selection is the process that determines which of the two strands in a miRNA duplex becomes the active strand that is incorporated into the RISC (RNA-induced silencing complex) (named the guide strand, leading strand or miR) and which one gets degraded (the passenger strand or miR*). Thermodynamic features of the duplex appear to play an important role in this decision; the strand with the weakest binding at its 5′-end is more likely to become the guide strand. Other key characteristics of human miRNA guide strands are a U-bias at the 5′-end and an excess of purines, whereas the passenger strands have a C-bias at the 5′-end and an excess of pyrimidines. Several proteins are known to play a role in strand selection [Ago (Argonaute), DICER, TRBP (trans-activation response RNA-binding protein), PACT (protein activator of dsRNA-dependent protein kinase) and Xrn-1/2]; however, the mechanisms by which these proteins act are largely unknown. For several miRNAs the miR/miR* ratio varies dependent on cell type, developmental stage and in different disease states, suggesting that strand selection is a tightly controlled process. The present review discusses our current knowledge regarding the factors and processes involved in strand selection and the many questions that still remain.
Skip Nav Destination
Article navigation
August 2014
- Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
Conference Article|
August 11 2014
Regulation of miRNA strand selection: follow the leader?
Hedda A. Meijer;
Hedda A. Meijer
1
*Medical Research Council (MRC) Toxicology Unit, Hodgkin Building, Lancaster Road, Leicester LE1 9HN, U.K.
Search for other works by this author on:
Ewan M. Smith;
Ewan M. Smith
*Medical Research Council (MRC) Toxicology Unit, Hodgkin Building, Lancaster Road, Leicester LE1 9HN, U.K.
Search for other works by this author on:
Martin Bushell
Martin Bushell
1
*Medical Research Council (MRC) Toxicology Unit, Hodgkin Building, Lancaster Road, Leicester LE1 9HN, U.K.
Search for other works by this author on:
Biochem Soc Trans (2014) 42 (4): 1135–1140.
Article history
Received:
May 14 2014
Citation
Hedda A. Meijer, Ewan M. Smith, Martin Bushell; Regulation of miRNA strand selection: follow the leader?. Biochem Soc Trans 1 August 2014; 42 (4): 1135–1140. doi: https://doi.org/10.1042/BST20140142
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.