Sanchez-Puerta M Virginia, Delwiche Charles F
Department of Biology, Indiana University, 1001 E 3rd St., Bloomington, Indiana 47405, USADepartment of Cell Biology and Molecular Genetics, University of Maryland College Park, College Park, Maryland 20742-5815, USA.
J Phycol. 2008 Oct;44(5):1097-107. doi: 10.1111/j.1529-8817.2008.00559.x. Epub 2008 Sep 3.
Four eukaryotic lineages, namely, haptophytes, alveolates, cryptophytes, and heterokonts, contain in most cases photosynthetic and nonphotosynthetic members-the photosynthetic ones with secondary plastids with chl c as the main photosynthetic pigment. These four photosynthetic lineages were grouped together on the basis of their pigmentation and called chromalveolates, which is usually understood to imply loss of plastids in the nonphotosynthetic members. Despite the ecological and economic importance of this group of organisms, the phylogenetic relationships among these algae are only partially understood, and the so-called chromalveolate hypothesis is very controversial. This review evaluates the evidence for and against this grouping and summarizes the present understanding of chromalveolate evolution. We also describe a testable hypothesis that is intended to accommodate current knowledge based on plastid and nuclear genomic data, discuss the implications of this model, and comment on areas that require further examination.
四个真核生物谱系，即定鞭藻、囊泡藻、隐藻和不等鞭毛藻，在大多数情况下都包含光合和非光合成员——光合成员具有以叶绿素c作为主要光合色素的次生质体。这四个光合谱系基于色素沉着被归为一类，称为色藻，通常认为这意味着非光合成员中质体的丧失。尽管这类生物具有生态和经济重要性，但这些藻类之间的系统发育关系仅得到部分理解，所谓的色藻假说极具争议性。本综述评估了支持和反对这种分类的证据，并总结了目前对色藻进化的理解。我们还描述了一个可检验的假说，旨在根据质体和核基因组数据整合当前知识，讨论该模型的影响，并对需要进一步研究的领域进行评论。
