miR-155-3p: processing by-product or rising star in immunity and cancer?

Dawson, Owen; Piccinini, Anna Maria

Abstract

MicroRNAs (miRNAs) are key players in gene regulation that target specific mRNAs for degradation or translational repression. Each miRNA is synthesized as a miRNA duplex comprising two strands (5p and 3p). However, only one of the two strands becomes active and is selectively incorporated into the RNA-induced silencing complex in a process known as miRNA strand selection. Recently, significant progress has been made in understanding the factors and processes involved in strand selection. Here, we explore the selection and functionality of the miRNA star strand (either 5p or 3p), which is generally present in the cell at low levels compared to its partner strand and, historically, has been thought to possess no biological activity. We also highlight the concepts of miRNA arm switching and miRNA isomerism. Finally, we offer insights into the impact of aberrant strand selection on immunity and cancer. Leading us through this journey is miR-155, a well-established regulator of immunity and cancer, and the increasing evidence that its 3p strand plays a role in these arenas. Interestingly, the miR-155-5p/-3p ratio appears to vary dependent on the timing of the immune response, and the 3p strand seems to play a regulatory role upon its partner 5p strand.

Citation

Dawson, O., & Piccinini, A. M. (2022). miR-155-3p: processing by-product or rising star in immunity and cancer?. Open Biology, 12(5), 843-854. https://doi.org/10.1098/rsob.220070

• Journal Article Type: Review
• Acceptance Date: May 11, 2022
• Online Publication Date: May 25, 2022
• Publication Date: May 25, 2022
• Deposit Date: May 25, 2022
• Publicly Available Date: May 25, 2022
• Journal: Open Biology
• Electronic ISSN: 2046-2441
• Publisher: The Royal Society
• Peer Reviewed: Peer Reviewed
• Volume: 12
• Issue: 5
• Pages: 843-854
• DOI: https://doi.org/10.1098/rsob.220070
• Keywords: General Biochemistry, Genetics and Molecular Biology; Immunology; General Neuroscience
• Public URL: https://nottingham-repository.worktribe.com/output/8221467
• Publisher URL: https://royalsocietypublishing.org/doi/10.1098/rsob.220070
• Additional Information: Received: 2022-03-09; Accepted: 2022-05-11; Published: 2022-05-25