Towards a Monograph of Jakobid, Trimastigid and Metamonad Protists

雅各布鞭毛虫可能是活着的真核生物中最原始的物种之一。来自自由雅各布和美洲弯胞单胞菌两个种的线粒体基因组的信息表明，雅各布的祖先是最早获得线粒体的真核生物之一。因此，Jakobids可能代表了一个研究真核细胞起源和早期分化的信息模型系统。为了更好地了解这些生物，需要了解它们的分类、多样性以及与其他原生生物的关系。我们目前还没有这方面的知识。在这项“概念验证”研究中，将对现有的雅各布鞭毛虫的物种描述进行汇编和批判性分析，并在存在的情况下检查模式标本。有关Jakobidae物种的形态、超微结构和生活史的数据将从发表的论文和对来自自然的物种的新调查中获得。这些数据将被用于构建系统发育分析的数据矩阵。核小亚单位核糖体RNA基因序列将从培育的物种中获得，用作物种识别符(例如，用于后续的分子探针设计)，并与形态数据一起用于系统发育分析。这些类别的初步数据将从三类原生生物的样本分类群中收集，这三组原生生物在许多方面与雅克虫非常相似，可能是它们的近亲。这项工作有望描述几个新的雅克比亚种，并初步评估雅各布与其他原虫之间的关系。由此产生的专著、在线和印刷形式，以及相关出版物，应该为对早期生物进化和微生物多样性感兴趣的人提供一个受欢迎的资源。

The jakobid flagellates may be among the most ancestral of livingeukaryotes. Information from the mitochondrial genomes of two jakobidspecies, Jakoba libera and Reclinomonas americana, suggests that theancestors of jakobids were among the first eukaryotes to acquiremitochondria. The jakobids, therefore, may represent an informative modelsystem for the study of the origin and early divergence of eukaryotic cells. To better understand these organisms, a knowledge of their taxonomicdiversity and relationship to other protists is required. We do not havethis knowledge at present.In this "proof of concept" study, existing species descriptions of jakobidflagellates will be assembled and critically analyzed, with examination oftype specimens when these exist. Data on the morphology, ultrastructure,and life history of jakobid species will be obtained from published papersand from new investigations on species isolated from nature. These datawill be used to construct data matrices for phylogenetic analysis. Nuclearsmall-subunit ribosomal RNA gene sequences will be obtained from cultivatedspecies for use as species identifiers (e.g., for subsequent molecularprobe design) and, with the morphological data, for phylogenetic analyses.Preliminary data in these categories will be collected from exemplar taxa ofTrimastigida, Retortamonadida and Diplomonadida, three groups of protiststhat closely resemble the jakobids in many ways and may be their closestrelatives.This work is expected to result in the description of several new jakobidspecies and in preliminary assessments of the relationships of jakobids witheach other and with other protists. The resulting monograph, online and inprint form, together with associated publications, should provide a welcomeresource for persons interested in early organismal evolution and microbialdiversity.