调控进化与形态多样性

Effects of regulatory evolution on morphological diversity

揭示导致生物体形态和结构多样性产生的原因和机制,是进化生物学研究的重要内容。进化发育生物学的研究表明,许多复杂的形态结构及其多样性,都是通过对古老调控网络的修饰或改造来完成的。也就是说,生物体形态和结构的多样化并不是像以前认为的是由基因编码区的变化造成的,而更多的是取决于基因的调控进化。作为控制基因表达的关键组分,基因调控区的顺式调控元件通过与特定反式作用因子结合,精细调控基因表达的时、空和量。因此,调控元件的获得、丢失、修饰或者改变都能引起基因表达模式的变化,是形态和结构多样性产生的主要原因。本文结合近年来国际上在基因的调控进化方面所取得的进展,总结了真核生物中基因调控的方式和特点,阐述了调控进化的基本式样,揭示了调控进化在生物进化(特别是形态和结构多样化)中的作用。

An important task in evolutionary biology is to understand the reason for and mechanisms of morphological diversification. Studies in evolutionary developmental biology have revealed that, rather than being invented repeatedly from scratch, many complex morphological structures have evolved by modification of ancient regulatory networks. In other words, morphological diversity is not always produced by changes in the protein-coding region of regulatory genes; rather, it largely depends on the evolution of gene regulation. As the main components of the regulatory regions of a gene, cis regulatory elements bind to specific ,trans factors and determine the precise expression of the gene in time, place and amount. As a result, gain, loss, change or modification of cis regulatory elements may lead to shifts in gene expression, which, in turn, generate morphological diversity. Here, by reviewing recent progress in this and related fields, we summarize the basic features of gene regulation in eukaryotes, elucidating its fundamental evolutionary pattern and revealing its importance in generating morphological diversity.