messenger RNA

American  

noun

Genetics.

1. a single-stranded molecule of RNA that is synthesized in the nucleus from a DNA template and then enters the cytoplasm, where its genetic code specifies the amino acid sequence for protein synthesis. mRNA

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messenger RNA British  

noun

1. Sometimes shortened to: mRNA.  biochem a form of RNA, transcribed from a single strand of DNA, that carries genetic information required for protein synthesis from DNA to the ribosomes See also transfer RNA genetic code

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messenger RNA Scientific  

/ mĕs′ən-jər /

1. See under RNA

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Etymology

Origin of messenger RNA

First recorded in 1960–65

Example Sentences

Kennedy and other health officials have criticized messenger RNA, or mRNA, technology that Moderna and other companies used for Covid-19 vaccines.

From The Wall Street Journal • Feb. 10, 2026

Using messenger RNA as an intermediary in their actions, the vaccines instruct the body how to manufacture parts of a pathogen that its immune system can recognize and fight.

From Los Angeles Times • Aug. 12, 2025

A cell transcribes the ORF sequence into messenger RNA, which travels to cellular factories called ribosomes that assemble amino acid sequences into proteins.

From Science Magazine • Nov. 24, 2024

But studies later suggested that the pricier messenger RNA vaccines made by Pfizer-BioNTech and Moderna provided better protection against COVID-19 and its many variants, and most countries switched to those shots.

From Seattle Times • May 8, 2024

Notably, Brenner and Jacob later discovered the messenger RNA was a facsimile of the DNA chain—a copy made from the original.

From "The Gene" by Siddhartha Mukherjee