在美国科学院院刊刊登的一则文章中，英国哥伦比亚大学植物学教授帕特里克?基林（Patrick Keeling）阐述了Chromera的基因组，以及它在疟疾和腰鞭毛虫藻进化历史中扮演的角色。
“在显微镜下，Chromera就像是简单的小褐色球，”基林说。“其实，海洋中到处都是褐色和绿色的小球，它们常常因为有更多迷人的有机生物而被忽略掉，但是它却比它那些浮华的‘表兄弟’更有趣。”
Chromera第一次被描述到是在2008年的《自然》杂志中，它在珊瑚中作为一种珊瑚的共生体被发现。尽管Chromera有一个分隔空间——质体，它和其他藻类及植物一样能产生光合作用，Chromera和包括疟疾在内的顶复门寄生虫很接近。Chromera可能将这两者联系到一起。
现在，基林和博士生简 扬欧斯科维克（Jan Janouskovec）、博士后阿勒斯 霍拉克和来自捷克共和国的同事们一起，已经把Chromera的质体基因组排序，并且找到了传承到顶复门寄生虫和腰鞭毛虫身上的特质，这种特质把这两个后裔联系在了一起。
“这些微小的有机生物对人类的各个方面都产生了巨大影响，”基林说。从某方面来说，腰鞭毛虫和Chromera对珊瑚共生使用的手段已经变成了一个传染机制，如同疟疾对人体健康细胞的影响。
“解析它们的进化源头不仅是解决一个长期存有争议的科学问题，也为对抗疾病和环境问题提供了至关重要的信息。”(生物谷Bioon.com)
生物谷推荐原文出处：
PNAS doi: 10.1073/pnas.1003335107
A common red algal origin of the apicomplexan, dinoflagellate, and heterokont plastids
Jan Janou?koveca, Ale? Horáka, Miroslav Oborníkb, Julius Luke?b, and Patrick J. Keelinga,1
Jan Janou?koveca, Ale? Horáka, Miroslav Oborníkb, Julius Luke?b, and Patrick J. Keelinga,1
The discovery of a nonphotosynthetic plastid in malaria and other apicomplexan parasites has sparked a contentious debate about its evolutionary origin. Molecular data have led to conflicting conclusions supporting either its green algal origin or red algal origin, perhaps in common with the plastid of related dinoflagellates. This distinction is critical to our understanding of apicomplexan evolution and the evolutionary history of endosymbiosis and photosynthesis; however, the two plastids are nearly impossible to compare due to their nonoverlapping information content. Here we describe the complete plastid genome sequences and plastid-associated data from two independent photosynthetic lineages represented by Chromera velia and an undescribed alga CCMP3155 that we show are closely related to apicomplexans. These plastids contain a suite of features retained in either apicomplexan (four plastid membranes, the ribosomal superoperon, conserved gene order) or dinoflagellate plastids (form II Rubisco acquired by horizontal transfer, transcript polyuridylylation, thylakoids stacked in triplets) and encode a full collective complement of their reduced gene sets. Together with whole plastid genome phylogenies, these characteristics provide multiple lines of evidence that the extant plastids of apicomplexans and dinoflagellates were inherited by linear descent from a common red algal endosymbiont. Our phylogenetic analyses also support their close relationship to plastids of heterokont algae, indicating they all derive from the same endosymbiosis. Altogether, these findings support a relatively simple path of linear descent for the evolution of photosynthesis in a large proportion of algae and emphasize plastid loss in several lineages (e.g., ciliates, Cryptosporidium, and Phytophthora).
