microRNA

noun
mi·​cro·​RNA | \ ˌmī-krō-ˌär-(ˌ)en-ˈā How to pronounce microRNA (audio) \
variants: or less commonly micro-RNA

Definition of microRNA

genetics
: a short segment of RNA that suppresses gene expression by binding to complementary segments of messenger RNA and interfering with the formation of proteins by translation (see translation sense 2) The 2006 Nobel Prize honored the discovery of RNA interference … and RNAi has helped shed light on the fact that cells naturally use RNA molecules just 20 to 22 nucleotides long, dubbed microRNAs, to regulate gene expression.— Jennifer Couzin

called also miRNA

First Known Use of microRNA

2001, in the meaning defined above

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The first known use of microRNA was in 2001

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Cite this Entry

“MicroRNA.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/microRNA. Accessed 27 Jan. 2021.

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More Definitions for microRNA

microRNA

noun
mi·​cro·​RNA | \ ˌmī-krō-ˌär-en-ˈā How to pronounce microRNA (audio) \
variants: also micro-RNA

Medical Definition of microRNA

: a short segment of RNA that suppresses gene expression by binding to complementary segments of messenger RNA and interfering with the formation of proteins during translation These microRNAs (miRNAs)—21 to 25 nucleotides in length—are negative regulators of gene expression.— Paul S. Meltzer, Nature, 9 June 2005

called also miRNA

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