microRNA

noun mi·cro·RNA \ ˌmī-krō-ˌär-(ˌ)en-ˈā \
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 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

See Words from the same year
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Medical Dictionary

microRNA

noun mi·cro·RNA \ ˌmī-krō-ˌär-en-ˈā \
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. MeltzerNature9 June 2005
called also miRNA

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