Expression analysis of LIM gene family in poplar, toward an updated phylogenetic classification.
Expression analysis of LIM gene family in poplar, toward an updated phylogenetic classification.
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DOI：
10.1186/1756-0500-5-102
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发表时间：
2012-02-17
影响因子：
1.8
通讯作者：
Pilate, Gilles
中科院分区：
文献类型：
--
作者：
Arnaud, Dominique;Dejardin, Annabelle;Pilate, Gilles
背景：植物LIM结构域蛋白可以作为木质素生物合成的转录激活因子和/或作为肌动蛋白结合和捆绑蛋白。植物LIM基因在系统发育亚群中进化，其表达谱不同：在整个植物中或特别是在花粉中。然而，几个白杨PtLIM基因属于uncharacterized单系亚群和LIM基因家族在木本plant. FININGS的表达模式还没有研究：在这项工作中，12个重复的白杨PtLIM基因的表达模式进行了研究，通过半定量RT-PCR在不同的营养和生殖组织。白杨PtLIM基因与其他植物一样，在树木或特定组织中广泛表达。PtXLIM 1a、PtXLIM 1b和PtWLIM 1b基因在次生木质部中优先表达，表明其在木材形成中具有特异功能。此外，这些基因和PtPLIM 2a基因的表达在张力木材中增加。Western-blot分析证实了PtXLIM 1a蛋白在木质部分化和张力木形成过程中的优先表达。属于花粉特异性PLIM 2和PLIM 2-like亚组的基因在花粉中强烈表达，但也在棉花毛中强烈表达。有趣的是，成对的重复PtLIM基因表现出不同的表达模式，表明特定组织中的亚功能化。结论：几种LIM基因在棉花毛和萌发花粉以及木质部纤维中的强表达表明植物LIM结构域蛋白参与了细胞的控制。扩展。白杨LIM基因的表达谱与已发表的密切相关的植物LIM基因的功能的比较表明，在木质素的生物合成，花粉管生长和机械应力响应领域的保守功能。基于这些结果，我们提出了一个新的命名白杨LIM结构域蛋白。
BACKGROUND: Plant LIM domain proteins may act as transcriptional activators of lignin biosynthesis and/or as actin binding and bundling proteins. Plant LIM genes have evolved in phylogenetic subgroups differing in their expression profiles: in the whole plant or specifically in pollen. However, several poplar PtLIM genes belong to uncharacterized monophyletic subgroups and the expression patterns of the LIM gene family in a woody plant have not been studied.FINDINGS: In this work, the expression pattern of the twelve duplicated poplar PtLIM genes has been investigated by semi quantitative RT-PCR in different vegetative and reproductive tissues. As in other plant species, poplar PtLIM genes were widely expressed in the tree or in particular tissues. Especially, PtXLIM1a, PtXLIM1b and PtWLIM1b genes were preferentially expressed in the secondary xylem, suggesting a specific function in wood formation. Moreover, the expression of these genes and of the PtPLIM2a gene was increased in tension wood. Western-blot analysis confirmed the preferential expression of PtXLIM1a protein during xylem differentiation and tension wood formation. Genes classified within the pollen specific PLIM2 and PLIM2-like subgroups were all strongly expressed in pollen but also in cottony hairs. Interestingly, pairs of duplicated PtLIM genes exhibited different expression patterns indicating subfunctionalisations in specific tissues.CONCLUSIONS: The strong expression of several LIM genes in cottony hairs and germinating pollen, as well as in xylem fibers suggests an involvement of plant LIM domain proteins in the control of cell expansion. Comparisons of expression profiles of poplar LIM genes with the published functions of closely related plant LIM genes suggest conserved functions in the areas of lignin biosynthesis, pollen tube growth and mechanical stress response. Based on these results, we propose a novel nomenclature of poplar LIM domain proteins.