# The life of an mRNA

> An mRNA is edited, sent to the right place, stored or read, and finally destroyed. Each step is a chance to control the protein it makes.

Source: https://khushisingh.in/explore/04-the-life-of-an-mrna/
Author: Khushi Singh (khushisingh.in). Licence: CC BY 4.0 for text and original illustrations, unless a credit says otherwise.
Evidence labels used on this site: established, strong evidence, emerging, hypothesis, debated. Where a page has Simple, Curious and Expert versions, all three follow.

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[Biology made simple](https://khushisingh.in/explore/) · How genes work · 4 of 8

About 2 minutes

**mRNA** is the messenger that carries a gene’s recipe to the ribosomes (Brenner et al. 1961). In plants, animals and fungi it is first edited: unneeded pieces are spliced out, and a cap and a tail are added. Some mRNAs are then carried to one part of the cell, to the tip of a nerve cell or the back of an egg, so that their protein is made exactly there; many wait, silent, in droplets of RNA and protein. (evidence: established)

Every mRNA is eventually destroyed: in bacteria most last a few minutes (Bernstein et al. 2002), in mammalian cells hours (Schwanhäusser et al. 2011). How long it lasts helps set how much protein is made. I see single mRNAs with smFISH, which lights each one up with dozens of small fluorescent probes (Raj et al. 2008).

*[Here the web page has an interactive activity; open the source URL to use it.]*

**In my research:** [Imaging single mRNAs in RNA–protein condensates →](https://khushisingh.in/research/oskar-condensates/)

## Sources

1. Brenner S, Jacob F, Meselson M (1961) An unstable intermediate carrying information from genes to ribosomes for protein synthesis. Nature 190:576–581. [doi:10.1038/190576a0](https://doi.org/10.1038/190576a0)
2. Bernstein JA, Khodursky AB, Lin PH, Lin-Chao S, Cohen SN (2002) Global analysis of mRNA decay and abundance in Escherichia coli at single-gene resolution using two-color fluorescent DNA microarrays. PNAS 99:9697–9702. [doi:10.1073/pnas.112318199](https://doi.org/10.1073/pnas.112318199)
3. Schwanhäusser B, et al. (2011) Global quantification of mammalian gene expression control. Nature 473:337–342. [doi:10.1038/nature10098](https://doi.org/10.1038/nature10098)
4. Raj A, van den Bogaard P, Rifkin SA, van Oudenaarden A, Tyagi S (2008) Imaging individual mRNA molecules using multiple singly labeled probes. Nature Methods 5:877–879. [doi:10.1038/nmeth.1253](https://doi.org/10.1038/nmeth.1253)