A tinkerer's tales | Nature Reviews Genetics

Access through your institution Buy or subscribe The three articles examine the routes that evolution takes in creating an adaptive function. One study, by Prud'homme, Gompel and

colleagues, concentrated on the black spot that exists on the male wing of some _Drosophila_ species. The wing spot has evolved independently in two lineages, where it is used to woo

females, and in both cases the evolution of the pattern involves the _yellow_ pigmentation gene. What is most interesting is that the _cis_-regulatory elements that have been used in the two

cases are distinct, indicating that evolution can use different mechanisms to reach a convergent, adaptive endpoint. The repeated use of the _yellow_ gene in different lineages raises

another theme in evolution — constraint. That constraint exists was the strong conclusion to emerge from the work of Weinreich and colleagues when they addressed a related issue: how many

paths can a protein take towards a fitter state? Their choice was the evolution of bacterial β-lactamase, which can evolve a 100,000-fold increase in antibiotic resistance by acquiring just

five point mutations. Of the 120 hypothetical trajectories to drug-resistant alleles, 102 are inaccessible to evolution. This prediction was based on the probability of fixation of mutant

combinations; in fact, the situation is more extreme than this, because of the 18 plausible combinations as few as 2 are probable, indicating that the path to adaptive protein evolution is

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taxes which are calculated during checkout ADDITIONAL ACCESS OPTIONS: * Log in * Learn about institutional subscriptions * Read our FAQs * Contact customer support REFERENCES ORIGINAL

RESEARCH PAPERS * Bridgham, J. T. et al. Evolution of hormone-receptor complexity by molecular exploitation. _Science_ 312, 97–101 (2006) Article  CAS  Google Scholar  * Weinreich, D. M. et

al. Darwinian evolution can follow only very few mutational paths to fitter proteins. _Science_ 312, 111–114 (2006) Article  CAS  Google Scholar  * Prud'homme, B. & Gompel, N. et

al. Repeated morphological evolution through cis-regulatory changes in a pleiotropic gene. _Nature_ 440, 1050–1053 (2006) Article  CAS  Google Scholar  FURTHER READING * Thornton, J.

Resurrecting ancient genes: experimental analysis of extinct molecules. _Nature Rev. Genet_. 5, 366–375 (2004) Article  CAS  Google Scholar  * DePristo, M. A. et al. Missense meanderings in

sequence space: a biophysical view of protein evolution. _Nature Rev. Genet._ 6, 678–687 (2005) Article  CAS  Google Scholar  Download references Authors * Tanita Casci View author

publications You can also search for this author inPubMed Google Scholar RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Casci, T. A tinkerer's

tales. _Nat Rev Genet_ 7, 411 (2006). https://doi.org/10.1038/nrg1874 Download citation * Published: 09 May 2006 * Issue Date: 01 June 2006 * DOI: https://doi.org/10.1038/nrg1874 SHARE THIS

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