由纽约大学进化生物学教授Sandie Baldauf和Dundee大学生化教授Professor Pauline Schaap率领的研究小组获得了现有的100种阿米巴虫（social amoeba）的分子图谱，由此现有的阿米巴虫（social amoeba）全部家族谱系（family tree）成功绘制完成，这是一个重大突破，为研究地球上的生命形式进化过程提供了重要线索。文章刊登于10月27日Science杂志。
利用新得到的家谱，研究人员设计出一种模型系统，用于解释单细胞生命怎样进行信号传递的，以及怎样依据环境条件改变而相互作用产生多细胞结构的。先前一直没有任何有关Dictyostelia阿米巴虫的分子数据（Dictyostelia阿米巴虫是一个巨大的、古老的阿米巴虫亚家族）。
阿米巴虫是一组遗传差异显著的生命形式，差异比真菌家族的还要大，与所有动物的差异相似。进化和信息传递研究在多细胞有机体中很难进行，阿米巴虫为这两种研究提供了极好的模型系统。
Dundee大学生命科科学院细胞分化和发育生物学教授Schaap说：“这给我们提供了分子水平研究物种进化和突变的起点。家谱的实用性使我们能够重演产生多细胞的信号机制的进化事件，为我们鉴别调节大多数基础发育事件的核心原始过程，提供了一件有力工具。”
纽约大学生物学部Baldauf教授说：“我们研究植物和动物的进化已经有很长一段时间的历史了，但是我们所有的生态系统依赖于单细胞有机体。如果想知道生命的基础，我们应该关注单细胞生命。”
“阿米巴虫是动物最亲的单细胞亲戚，因此弄清它们的工作和进化机制非常重要，有助于我们研究动物进化过程。我们已经为研究生命模式进化建立了一种新的模式系统。”
“我们已经编撰了字典，现在我们知道了单词的意思，但是我们还需要造句。”
研究小组通过扩大和对比所有已知的阿米巴虫的高度保守基因，绘制得到了阿米巴虫家谱。现有的家谱都是基于各个物种多细胞结构的外观。然而，Dundee 和York大学研究人员获得阿米巴虫家谱完全植根于分子数据。通过将现有的阿米巴虫的所有信息——细胞、多细胞形式、行为等加入分子树测绘分析，显示细胞特化增强，有机体大小是阿米巴虫进化的主要趋势。
Schaap教授及其同事目前正研究在产生新细胞类型和形态特征的进化过程中，重要基因的功能是怎样改变的。Baldauf及其同事接下来的任务是研究阿米巴虫的起源，寻找新的种类，并将它们按顺组排列在家谱上。同时，美国和德国的一些研究小组已获得资助，对York 和Dundee大学研究的阿米巴虫的基因组进行测序。
英文原文：
Scientists’ cell discovery unearths evolutionary clues
The full family tree of the species known as social amoebas has been plotted for the first time - a breakthrough which will provide important clues to the evolution of life on earth.
Researchers, headed by biochemist Professor Pauline Schaap, of the University of Dundee, and evolutionary biologist Professor Sandie Baldauf, of the University of York, have produced the first molecular ‘dictionary’ of the 100 or so known species of social amoeba.
Using this family tree, they have devised a model system to establish how single cell organisms communicate and interact to create multi-cellular structures in response to changing environmental conditions. Previously, there was almost no molecular data for social amoeba - Dictyostelia - which are a hugely diverse and ancient group.
Social amoebas are a group of organisms with a genetic diversity that is greater than that of fungi and similar to that of all animals. They offer an excellent experimental system for studying aspects of evolution and communication that are not easy to study in more complex multi-cellular organisms.
The York and Dundee teams have worked with field biologists in Germany, the US and Japan, and their research is published today (Friday 27th October 2006) in the prestigious international journal Science.
"This provides a starting point in allowing us to examine what happens at the molecular level as species evolve and mutate," said Professor Schaap, of the Division of Cell and Developmental Biology in the College of Life Sciences at Dundee.
"The availability of a family tree allows us to reconstruct the evolution of the signalling mechanisms that generate multicellularity. It also provides a powerful tool to identify core ancestral processes that regulate the most basic aspects of development."
Professor Baldauf, of the Department of Biology at York, said: "We have investigated the evolution of plants and animals for a very long time but our whole eco-system depends on single cell organisms. If we want to look at the fundamentals of life we have to look at single cell organisms."
"Amoebas are some of the closest single cell relatives of animals so understanding how they work and evolve is important because it helps us to understand how animals evolve. We have developed a new model system for the study of the evolution of forms."
"We have written the dictionary. Now we know what the words are -- but we still have to construct the sentences."
The research teams were able to build the family tree by amplifying and comparing highly conserved genes from all known species of social amoeba.
The existing family tree of the social amoeba was based on how the multicellular structures of each species look on the outside. However, this tree was completely uprooted by the molecular data gathered by the researchers in Dundee and York.
By plotting all existing information of the amoebas’ cellular and multi-cellular shapes and behaviour to the molecular tree, it appeared that increased cell specialization and organism size is a major trend in the evolution of social amoeba.
Professor Schaap and her team are now working to establish how the regulation and function of genes with important roles in development was altered and elaborated during the course of evolution to generate novel cell-types and morphological features.
The next step for Professor Baldauf and her team will be to investigate the origin of these amoebas, and also to search for new species and to establish their position on the family tree. Meanwhile, a number of research projects, including teams in the USA and Germany, have won sponsorship to sequence the genomes of social amoeba species identified by the work in York and Dundee.
The Dundee-York project was funded under the Biotechnology and Biological Sciences Research Council (BBSRC) CODE (COmparative DEvelopment) initiative and took four years to complete.
