The collection of components required to carry out the intricate processes involved in generating and maintaining a living, breathing and, sometimes, thinking organism is staggeringly complex. Where do all of the parts come from? Early estimates stated that about 100,000 genes would be required to make up a mammal; however, the actual number is less than one-quarter of that, barely four times the number of genes in budding yeast. It is now clear that the 'missing' information is in large part provided by alternative splicing, the process by which multiple different functional messenger RNAs, and therefore proteins, can be synthesized from a single gene.
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We apologize to the many authors whose publications are not cited directly because of space limitations. Research in our laboratories is supported by grants from the National Institutes of Health (T.W.N. and B.R.G.), the Raymond and Beverly Sackler Fund for the Arts and Sciences (B.R.G.) and the State of Connecticut's Stem Cell Research Fund (B.R.G.).
The authors declare no competing financial interests.
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Nilsen, T., Graveley, B. Expansion of the eukaryotic proteome by alternative splicing. Nature 463, 457–463 (2010). https://doi.org/10.1038/nature08909