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之谜。为了解决这个问题，可能需要探索被子植物的姐妹类群——现存裸子植物生殖器官形成的遗传基础。不幸的是，所有现存的裸子植物都是木本植物，需要很多年才能进入繁殖阶段，因此不容易研究。然而，一个独特的机会来研究裸子植物的发育遗传学是由两个分离种群的自然同源和异时云杉品种“Acrocona”提供的，其特点是雌性球果的早熟发育在错误的位置，即芽的末端位置，并通过偶尔的雌雄同体球果的发展。为了深入了解裸子植物生殖发育的分子遗传学基础，我们希望通过比较花发育控制基因的同源基因和近缘基因在一个分离种群中突变型和野生型植株中的表达模式。此外，这些基因的一个选择子集将被定位在云杉染色体连锁图上，与其他Acrocona群体产生表型共分离研究，旨在通过候选基因方法克隆基因，并使用Acrocona基因作为第一个测试案例。我们的项目是最早用分子遗传学的方法研究发育控制基因在裸子植物繁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.