Molecular cloning and localization of a novel cotton annexin gene expressed preferentially during fiber development
Molecular cloning and localization of a novel cotton annexin gene expressed preferentially during fiber development
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DOI：
10.1007/s11033-009-9919-2
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发表时间：
2010-10-01
影响因子：
2.8
通讯作者：
Guo, Wang Zhen
中科院分区：
文献类型：
--
作者：
Wang, Li Ke;Niu, Xiao Wei;Guo, Wang Zhen
膜联蛋白是一个多功能和结构相关的蛋白家族。这些蛋白在植物界普遍存在，是重要的钙依赖性膜结合蛋白，参与植物不同区域的极性发育，如根状体、根冠和花粉管尖端。本研究从棉花（Gossypium hirsutum）纤维cDNA文库中分离到一个新的棉膜联蛋白基因（命名为GhFAnnx）。GhFAnnx全长cDNA包括一个945 bp的开放阅读框，编码314个氨基酸的蛋白，计算分子质量为35.7 kDa，等电点为6.49。不同棉花品种TM-1、Hai7124和2个二倍体祖先棉花G. herbaceum （a基因组）和G. raimondii （d基因组）的基因组GhFAnnx序列显示，在异源四倍体棉花基因组中至少鉴定出2个GhFAnnx基因拷贝，每个基因在编码区具有6个外显子和5个内含子。本研究从cDNA文库中克隆的GhFAnnx基因定位在四倍体棉花a -亚基因组的第10染色体上。序列比对显示GhFAnnx包含70个氨基酸的4个重复序列。半定量逆转录聚合酶链反应显示GhFAnnx在不同发育纤维中优先表达，但在根、茎和叶中表达量较低。GhFAnnx在洋葱表皮细胞和棉纤维中的亚细胞定位表明，该蛋白普遍存在于洋葱表皮细胞中，但聚集在棉纤维尖端的边缘和内侧，有明亮的斑点。综上所述，GhFAnnx影响纤维的发育，并与棉纤维在伸长阶段的极性膨胀有关。
Annexins constitute a family of multifunction and structurally related proteins. These proteins are ubiquitous in the plant kingdom, and are important calcium-dependent membrane-binding proteins that participate in the polar development of different plant regions such as rhizoids, root caps, and pollen tube tips. In this study, a novel cotton annexin gene (designated as GhFAnnx) was isolated from a fiber cDNA library of cotton (Gossypium hirsutum). The full-length cDNA of GhFAnnx comprises an open reading frame of 945 bp that encodes a 314-amino acid protein with a calculated molecular mass of 35.7 kDa and an isoelectric point of 6.49. Genomic GhFAnnx sequences from different cotton species, TM-1, Hai7124 and two diploid progenitor cottons, G. herbaceum (A-genome) and G. raimondii (D-genome) showed that at least two copies of the GhFAnnx gene, each with six exons and five introns in the coding region, were identified in the allotetraploid cotton genome. The GhFAnnx gene cloned from the cDNA library in this study was mapped to the chromosome 10 of the A-subgenome of the tetraploid cotton. Sequence alignment revealed that GhFAnnx contained four repeats of 70 amino acids. Semi-quantitative reverse transcriptase-polymerase chain reaction revealed that GhFAnnx is preferentially expressed in different developmental fibers but its expression is low in roots, stems, and leaves. Subcellular localization of GhFAnnx in onion epidermal cells and cotton fibers suggests that this protein is ubiquitous in the epidermal cells of onion, but assembles at the edge and the inner side of the apex of the cotton fiber tips with brilliant spots. In summary, GhFAnnx influences fiber development and is associated with the polar expansion of the cotton fiber during elongation stages.