Evolutionary history of HOMEODOMAIN LEUCINE ZIPPER transcription factors during plant transition to land

First author: Facundo Romani; Affiliations: Universidad Nacional del Litoral (阿根廷国立利特瑞尔大学): Santa Fe, Argentina

Corresponding author: Javier E. Moreno

Plant transition to land required several regulatory adaptations. The mechanisms behind these changes remain unknown. Since the evolution of transcription factors (TFs) families accompanied this transition, we studied the HOMEODOMAIN LEUCINE ZIPPER (HDZ) TF family known to control key developmental and environmental responses. We performed a phylogenetic and bioinformatics analysis of HDZ genes using transcriptomic and genomic datasets from a wide range of Viridiplantae species (绿色植物). We found evidence for the existence of HDZ genes in chlorophytes (绿藻) and early‐divergent charophytes (轮藻) identifying several HDZ members belonging to the four known classes (I–IV). Furthermore, we inferred a progressive incorporation of auxiliary (附加的) motifs. Interestingly, most of the structural features were already present in ancient lineages. Our phylogenetic analysis inferred that the origin of classes I, III, and IV is monophyletic in land plants in respect to charophytes. However, class II HDZ genes have two conserved lineages in charophytes and mosses that differ in the CPSCE motif. Our results indicate that the HDZ family was already present in green algae. Later, the HDZ family expanded accompanying critical plant traits. Once on land, the HDZ family experienced multiple duplication events that promoted fundamental neo‐ and subfunctionalizations for terrestrial life.

植物从原始的水生状态向陆生的转变涉及到一些调控的适应，然而目前我们对于这种改变的分子机制还不清楚。转录因子的演化会随着这种植物向陆生的转变一起进行，作者在本文中详细研究了对于发育和环境响应非常重要的同源结构域亮氨酸拉链HDZ转录因子家族。作者通过利用转录组和基因组数据对于许多绿色植物的HDZ基因进行了进化和生信分析。分析显示HDZ基因在绿藻类植物和早期分化形成的轮藻类植物中就已经存在，这些HDZ基因分属于已知的I–IV类亚家族。此外，作者还鉴定到了一次HDZ基因进化过程中合并附属基序事件。有趣的是，大多数的结构特征在古老的植物支系中就已经存在。本文的进化分析显示HDZ基因家族I、III、IV都是轮藻单系起源，而II类HDZ基因在轮藻和苔藓中存在两个保守的支系，这两者主要区别在于CPSCE基序。本文的结果揭示了HDZ家族在绿藻中就已经存在。之后，HDZ随着植物重要的性状演化不断的扩增。植物进入陆地之后，HDZ家族经历了多次的复制事件，从而促进了HDZ基因适应陆地的新功能化或亚功能化。

doi: https://doi.org/10.1111/nph.15133

Journal: New Phytologist

First Published date: 10 April, 2018

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