CoMPLEX, University College London, UK.
BMC Evol Biol. 2010 Dec 16;10:388. doi: 10.1186/1471-2148-10-388.
Sex determination networks evolve rapidly and have been studied intensely across many species, particularly in insects, thus presenting good models to study the evolutionary plasticity of gene networks.
We study the evolution of an unlinked gene capable of regulating an existing diploid sex determination system. Differential gene expression determines phenotypic sex and fitness, dramatically reducing the number of assumptions of previous models. It allows us to make a quantitative evaluation of the full range of evolutionary outcomes of the system and an assessment of the likely contribution of sexual conflict to change in sex determination systems. Our results show under what conditions network mutations causing differential regulation can lead to the reshaping of sex determination networks.
The analysis demonstrates the complex relationship between mutation and outcome: the same mutation can produce many different evolved populations, while the same evolved population can be produced by many different mutations. Existing network structure alters the constraints and frequency of evolutionary changes, which include the recruitment of new regulators, changes in heterogamety, protected polymorphisms, and transitions to a new locus that controls sex determination.
性别决定网络在许多物种中迅速进化，并受到了广泛研究，尤其是在昆虫中，因此为研究基因网络的进化可塑性提供了良好的模型。
我们研究了一个能够调节现有二倍体性别决定系统的非连锁基因的进化。差异基因表达决定了表型性别和适应性，大大减少了以前模型的假设数量。这使我们能够对系统的全部进化结果进行定量评估，并评估性冲突对性别决定系统变化的可能贡献。我们的研究结果表明，在何种条件下，导致差异调节的网络突变可以导致性别决定网络的重塑。
该分析表明了突变和结果之间的复杂关系：相同的突变可以产生许多不同的进化种群，而相同的进化种群也可以由许多不同的突变产生。现有的网络结构改变了进化变化的约束和频率，其中包括新调节因子的招募、异型性的改变、保护多态性以及向控制性别决定的新基因座的转变。
