Evolutionary developmental genetics of Norway spruce variety Picea abies 'Acrocona'

被子植物花在进化过程中的快速起源和多样化仍然是一个科学谜团。要解决这一问题，可能需要探索被子植物的姐妹群--现存的裸子植物--生殖器官形成的遗传基础。遗憾的是，现存的裸子植物都是木本植物，需要多年才能进入繁殖阶段，因此很难调查。然而，天然同源异性云杉品种‘Acrocona’的两个分离种群为研究裸子植物的发育遗传学提供了一个独特的机会，其特征是雌性球果的早熟发育在错误的位置，即新梢的末端位置，以及偶尔的两性球果的发育。为了更深入地了解裸子植物生殖发育的分子遗传学基础，我们想要比较花发育控制基因的同源基因和近亲在Acrocona分离的一个群体的突变体和野生型植物中的表达模式。此外，这些基因中选定的一个子集将位于与其他Acrocona种群一起生成的云杉染色体连锁图谱上，用于旨在通过候选基因方法进行基因克隆的表型共分离研究，并将ACROCONA基因作为第一个测试案例。我们的项目是第一批通过分子遗传学研究发育控制基因在裸子植物生殖中的作用的项目之一。

The rapid origin and diversification of the angiosperm flower during evolution is still a scientific mystery. To solve it may require that the genetic basis of reproductive organ formation in the putative sister group of the angiosperms, extant gymnosperms, is explored. Unfortunately, all extant gymnosperms are woody plants that require many years to enter the reproductive stage and hence are not easy to investigate. However, a unique opportunity to study the developmental genetics of gymnosperms is provided by two segregating populations of the natural homeotic and heterochronic spruce variety ‘Acrocona’, which is characterised by the precocious development of female cones at wrong, i.e. terminal positions of shoots, and by the occasional development of hermaphroditic cones. We want to compare the expression patterns of orthologues and close relatives of flower developmental control genes in mutant and wild-type plants of one of the populations segregating for Acrocona in order to get deeper insights into the molecular genetic basis of reproductive development in a gymnosperm. In addition, a selected subset of these genes will be located on a spruce chromosomal linkage map generated with the other Acrocona population for phenotypic co-segregation studies aiming at gene cloning by candidate gene approaches, and using the ACROCONA gene here as a first test case. Our project is among the very first studying the role of developmental control genes in gymnosperm reproduction by means of molecular genetics.