Nature Reviews Genetics 15, 65 (2014)

In this In Brief, the incorrect journal was listed in the citation. The citation should have been: Chandrasekaran, S. & Price, N. D. Metabolic constraint-based refinement of transcriptional regulatory networks. PLoS Comput. Biol. 9, e1003370 (2013). The article has been corrected online. The editors apologize for this error.