金粟兰科物种花同源异型MADS-box基因的功能和进化特征

Duplicate genes may be retained by sub- and/or neo-functionalization through shifts in gene expression and/or coding sequence, and therefore contribute to innovations of organism morphological features. The MADS-box gene family in plants encoding key transcription factors, many of which play an important role in the regulation of the flower development, has undergone extensive gene duplication events. Given their critical roles in shaping flower architecture, functional diversification following gene duplication within the MADS-box gene family is believed to be responsible to a large extent for the morphological innovations of the land plants. The phylogeny suggests that the early angiosperm flowers had spiral phyllotaxis, with a small but indeterminate number of undifferentiated perianth organs. From this simple flower, a whorled floral arrangement, with a fixed number of sepals and petals, evolved quite early in angiosperm. Chloranthaceae, as basal angiosperms, consists of the genera Chloranthus, Sarcandra, Ascarina and Hedyosmum, in which the flowers of the derived Chloranthus, Sarcandra and Ascarina possess no perianth, whereas the ancestral Hedyosmum possesses a perianth in female flowers. Thus, the family is important for understanding the early diversification of angiosperms. Our interest is to learn more about the relationship between the phylogeny of MADS-box genes and the dramatic deviations of floral structures in the species of Chloranthaceae from the "standard" flower built-plan.

在被子植物的进化过程中，MADS-box基因家族成员的基因重复、功能分化、互作网络精细调控等等分子机理是导致被子植物花的形态多样性的重要推动力。阐明植物被子植物基部类群花器官发育的分子遗传机理，对于认识整个被子植物花多样性的进化研究是非常关键的。基部被子植物类群金粟兰科植物既具有最简单的花，也具有相对复杂的不完全花。本项目结合前期工作，对金粟兰科中亲缘关系相近、而花部形态差异较大的两个物种中的花同源异型MADS-box基因的功能进行遗传学和比较遗传学整合分析，为揭示MADS-box基因功能演化模式与花器官形态分化发育的关联提供新的分子遗传学证据。

在被子植物的进化过程中，MADS-box基因家族成员的基因重复、功能分化、互作网络精细调控等等分子机理是导致被子植物花的形态多样性的重要推动力。阐明植物被子植物基部类群花器官发育的分子遗传机理，对于认识整个被子植物花多样性的进化研究是非常关键的。基部被子植物类群金粟兰科植物既具有最简单的花，也具有相对复杂的不完全花。在本项目的资助下,对金粟兰科中亲缘关系相近、而花部形态差异较大的两个物种金粟兰和雪香兰中的花同源异型MADS-box基因的功能进行了遗传学和比较遗传学整合分析，为揭示MADS-box基因功能演化模式与花器官形态分化发育的关联提供了新的分子遗传学证据。