New insights into evolution of gene expression

Major organ-altering evolutionary events such as development of the hominoid brain are also associated with gene expression shifts. However, although gene duplication is well-known to play an important role in expression pattern shifts, the evolutionary dynamics of expression patterns with and without gene duplication remain poorly understood.

"An important question is whether long-term expression in one organ predisposes genes to be subsequently utilized in other organs. The answer is yes," says Dr. Kenji Fukushima from Julius-Maximilians-Universität (JMU) Würzburg in Bavaria, Germany. "There are preadaptive propensities in the evolution of vertebrate gene expression, and the propensity varies with the presence and type of gene duplication."

Kenji Fukushima now reports this and other findings with his co-author David D. Pollock (University of Colorado, School of Medicine, Aurora, USA) in the journal Nature Communications.

Complex history of gene family trees

For their study the scientists amalgamated 1,903 RNA-seq datasets from 182 research projects. The date include six organs (brain, heart, kidney, liver, ovary, and testis) from 21 vertebrate species, ranging from freshwater fish and frogs to lizards, birds, rodents and humans. So they revealed a complex history of gene family trees. This allowed them to analyse the evolutionary expression of a broad set of genes.