蚂蚁翅多型性基因网络中发育系统漂变的动力学:一个数学模型
The dynamics of developmental system drift in the gene network underlying wing polyphenism in ants: a mathematical model.
作者信息
Nahmad Marcos, Glass Leon, Abouheif Ehab
机构信息
Department of Physics, McGill University, Montreal, Quebec H3A 2T8, Canada.
出版信息
Evol Dev. 2008 May-Jun;10(3):360-74. doi: 10.1111/j.1525-142X.2008.00244.x.
Understanding the complex interaction between genotype and phenotype is a major challenge of Evolutionary Developmental Biology. One important facet of this complex interaction has been called "Developmental System Drift" (DSD). DSD occurs when a similar phenotype, which is homologous across a group of related species, is produced by different genes or gene expression patterns in each of these related species. We constructed a mathematical model to explore the developmental and evolutionary dynamics of DSD in the gene network underlying wing polyphenism in ants. Wing polyphenism in ants is the ability of an embryo to develop into a winged queen or a wingless worker in response to an environmental cue. Although wing polyphenism is homologous across all ants, the gene network that underlies wing polyphenism has evolved. In winged ant castes, our simulations reproduced the conserved gene expression patterns observed in the network that controls wing development in holometabolous insects. In wingless ant castes, we simulated the suppression of wings by interrupting (up- or downregulating) the expression of genes in the network. Our simulations uncovered the existence of four groups of genes that have similar effects on target gene expression and growth. Although each group is comprised of genes occupying different positions in the network, their interruption produces vestigial discs that are similar in size and shape. The implications of our results for understanding the origin, evolution, and dissociation of the gene network underlying wing polyphenism in ants are discussed.
理解基因型与表型之间的复杂相互作用是进化发育生物学面临的一项重大挑战。这种复杂相互作用的一个重要方面被称为“发育系统漂变”(DSD)。当一组相关物种中同源的相似表型由这些相关物种中各自不同的基因或基因表达模式产生时,就会发生发育系统漂变。我们构建了一个数学模型,以探究蚂蚁翅多型性潜在基因网络中发育系统漂变的发育和进化动态。蚂蚁的翅多型性是指胚胎根据环境线索发育成有翅蚁后或无翅工蚁的能力。尽管翅多型性在所有蚂蚁中都是同源的,但翅多型性潜在的基因网络已经进化。在有翅蚁 caste 中,我们的模拟重现了在全变态昆虫控制翅发育的网络中观察到的保守基因表达模式。在无翅蚁 caste 中,我们通过中断(上调或下调)网络中基因的表达来模拟翅的抑制。我们的模拟揭示了四组对靶基因表达和生长有相似影响的基因的存在。尽管每组基因在网络中占据不同位置,但它们的中断会产生大小和形状相似的残翅盘。我们讨论了这些结果对于理解蚂蚁翅多型性潜在基因网络的起源、进化和解离的意义。