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miRNA

noun \ ˌem-ˌī-ˌär-(ˌ)en-ˈā \

Definition of miRNA

genetics

: microrna

A major part of this regulation is performed by microRNAs (miRNAs), small RNA molecules encoded by the genome that are not translated into proteins; rather, they control the expression of genes.
—Sebastien S. Hebert et al.

First Known Use of mirna

2001

in the meaning defined above

See Words from the same year

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Medical Dictionary

miRNA

noun \ ˌem-ˌī-ˌär-ˌen-ˈā \

medical Definition of miRNA

: microrna

MicroRNAs (miRNAs) are 20- to 22-nucleotide RNAs that regulate the function of eukaryotic messenger RNAs (mRNAs) and play important roles in development, cancer, stress responses, and viral infections.
—J. Ross Buchan et al., Science, 21 Dec. 2007

Many of the noncoding RNAs, epitomized by the miRNA, have regulatory functions in normal cells. The aberrant expression of miRNA promotes tumorigenesis, metastasis, and other features of cancer.
—Frank J. Slack et al., The New England Journal of Medicine, 18 Dec. 2008

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