Cotton AnnGh3 Encoding an Annexin Protein is Preferentially Expressed in Fibers and Promotes Initiation and Elongation of Leaf Trichomes in Transgenic Arabidopsis

The annexins are a multifamily of calcium-regulated phospholipid-binding proteins. To investigate the roles of annexins in fiber development, four genes encoding putative annexin proteins were isolated...     

Cotton LIM domain‐containing protein GhPLIM1 is specifically expressed in anthers and participates in modulating F‐actin

As one form of actin binding protein (ABP), LIM domain protein can trigger the formation of actin bundles during plant growth and development. In this study, a cDNA (designated GhPLIM1) encoding a LIM domain protein with 216 amino acid residues was identified from a cotton flower cDNA library. Quantitative RT‐PCR indicated that GhPLIM1 is specifically expressed in cotton anthers, and its expression levels are regulated during anther development of cotton. GhPLIM1:eGFP transformed cotton cells display a distributed network of eGFP fluorescence, suggesting that GhPLIM1 protein is mainly localised to the cell cytoskeleton. In vitro high‐speed co‐sedimentation and low co‐sedimentation assays indicate that GhPLIM1 protein not only directly binds actin filaments but also bundles F‐actin. Further biochemical experiments verified that GhPLIM1 protein can protect F‐actin against depolymerisation by Lat B. Thus, our data demonstrate that GhPLIM1 functions as an actin binding protein (ABP) in modulating actin filaments in vitro, suggesting that GhPLIM1 may be involved in regulating the actin cytoskeleton required for pollen development in cotton.     

陆地棉SUPERMAN类似锌指蛋白基因的克隆与表达分析

锌指蛋白是生物体内数量最多的转录调控因子,它在动植物的生长发育中都起到十分重要的作用。SUPERMAN类锌指蛋白只含有1个锌指结构。我们根据这类蛋白的保守结构域设计简并引物,通过RT-PCR从棉花中获得了3个这个家族成员的EST,得到1个锌指蛋白基因的全长序列,该基因的编码区长744 bp,编码长248个氨基酸的多肽,其氨基酸序列与GenBank中登录的一个拟南芥RBE蛋白有40%的同源性。此基因被命名为GZFP。它含有保守的锌指结构并在多肽链的C-端具有富含亮氨酸的保守结构域,GZFP含有核定位信号并且没有内含子。GZFP基因在棉花花蕾、子房、花瓣和根中的表达量要高于木质部、韧皮部、叶片、纤维和种子。GZFP基因的表达量很低,在GenBank中没有任何和它同源的EST序列存在。对GZFP 5′侧翼区进行分析发现有数个花粉和根特异表达相关元件,4个与Dof蛋白作用的核心序列,4个与光诱导相关的元件。      

棉花GhAQP1基因克隆及其在胚珠发育中的特异表达

从棉花cDNA文库中筛选分离了1个编码PIP1类水孔蛋白的CDNA序列,编码287个氨基酸,命名为GhAQP1。该基因全长2096bp,编码区内含有2个内含子,分别位于编码第五和第六跨膜螺旋的碱基序列内。Northern杂交结果显示,GhAQP1基因主要在胚珠中表达,在开花后9d的胚珠中表达量最高,表明其表达不仅具有组织特异性,而且是受胚珠发育调节的。     

Response of the enzymes to nitrogen applications in cotton fiber (Gossypium hirsutum L.) and their relationships with fiber strength

To investigate the response of key enzymes to nitrogen (N) rates in cotton fiber and its relationship with fiber strength, experiments were conducted in 2005 and 2006 with cotton cultivars in Nanjing. Three N rates 0, 240 and 480 kgN/hm2, signifying optimum and excessive nitrogen application levels were applied.The activities and the gene expressions of the key enzymes were affected by N, and the characteristics of cellulose accumulation and fiber strength changed as the N rate varied. Beta-1,3-glucanase activity in cotton fiber declined from 9 DPA till boll opening, and the beta-1, 3-glucanase coding gene expression also followed a unimodal curve in 12—24 DPA. In 240 kgN/hm² condition, the characteristics of enzyme activity and gene expression manner for sucrose synthase and beta-1,3-glucanase in developing cotton fiber were more favorable for forming a longer and more steady cellulose accumulation process, and for high strength fiber development.     

Nucleolar size at early stages of cotton fiber development in relation to final fiber dimension

Changes in nucleolar size and nucleolar vacuolation at early stages of fiber development and final fiber dimensions were determined for cotton of different species: Gossypium hirsutum L. cv. B49, Gossypium barbadense L. cv. Menoufi and Gossypium arboreum L. cv. Virnar. Size of the nucleolus in combination with its vacuolation at an early stage of development was found to be clearly associated with the final result of fiber development.     

RiceAntherNet: a gene co‐expression network for identifying anther and pollen development genes

In plants, normal anther and pollen development involves many important biological events and complex molecular regulatory coordination. Understanding gene regulatory relationships during male reproductive development is essential for fundamental biology and crop breeding. In this work, we developed a rice gene co‐expression network for anther development (RiceAntherNet) that allows prediction of gene regulatory relationships during pollen development. RiceAntherNet was generated from 57 rice anther tissue microarrays across all developmental stages. The microarray datasets from nine rice male sterile mutants, including msp1‐4, ostdl1a, gamyb‐2, tip2, udt1‐1, tdr, eat1‐1, ptc1 and mads3‐4, were used to explore and test the network. Among the changed genes, three clades showing differential expression patterns were constructed to identify genes associated with pollen formation. Many of these have known roles in pollen development, for example, seven genes in Clade 1 (OsABCG15, OsLAP5, OsLAP6, DPW, CYP703A3, OsNP1 and OsCP1) are involved in rice pollen wall formation. Furthermore, Clade 1 contained 12 genes whose predicted orthologs in Arabidopsis have been reported as key during pollen development and may play similar roles in rice. Genes in Clade 2 are expressed earlier than Clade 1 (anther stages 2–9), while genes in Clade 3 are expressed later (stages 10–12). RiceAntherNet serves as a valuable tool for identifying novel genes during plant anther and pollen development. A website is provided ( https://www.cpib.ac.uk/anther/riceindex.html ) to present the expression profiles for gene characterization. This will assist in determining the key relationships between genes, thus enabling characterization of critical genes associated with anther and pollen regulatory networks.     

一个陆地棉bZIP蛋白cDNA的克隆及表达分析

利用PCR筛选方法从陆地棉纤维cDNA文库中筛选到一个全长cDNA序列,命名为GhbZIP。其编码产物长度为645个氨基酸残基,序列中含有两个未知功能的保守区域DUF630和DUF632,而DUF632区中有一个类似碱性亮氨酸拉链基元;此外氨基酸序列中还存在一个富脯氨酸区和一个富苯丙氨酸区,因此该蛋白具有植物碱性亮氨酸拉链蛋白的结构特征。亲水性分析表明,GhbZIP为一个典型的膜蛋白。GhbZIP基因主要是在开花3d之后在胚珠和纤维细胞中表达,这表明该基因可能与棉纤维伸长过程中的基因表达调控有关。     

一年生陆地棉细胞核雄性不育系洞A的宿生栽培效应

植物细胞核雄性不育系具有易于恢复但保持困难的特点。根据广西南部冬季无霜冻的气候特点,在广西南宁进行了一年生陆地棉细胞核雄性不育系洞A的三年露地栽培。结果表明:二、三年生洞A在5月上旬开花、6月下旬吐絮,这是一年生洞A在相同环境条件下难以达到的;与一年生洞A相比,二、三年生洞A的子指、单株铃数、产量显著增加,但单铃重、衣分显著下降,僵瓣率显著增加;纤维品质基本没有显著变化。说明利用陆地棉细胞核雄性不育系在南亚热带的宿生栽培进行良种繁育具有较好的前景。     

一类新的编码PRPs基因的分离及其在棉花纤维等组织细胞中的表达

富含脯氨酸的细胞壁蛋白(proline-rich proteins,PRPs)在植物中广泛分布,它们在建造围绕特定细胞类型的细胞壁结构上起着很重要的作用.从棉花的cDNA文库中分离了5个编码富含脯氨酸的细胞壁蛋白质基因,这5个基因推断的氨基酸序列最普遍的特点就是脯氨酸含量非常高.根据氨基酸组成、富含脯氨酸的重复单元和结构域组织的特点,将这5个蛋白质分成2个亚类:一类(包括GhPRP3-6)与典型的PRPs结构相似,由N端疏水区(或信号肽)与不同富含脯氨酸的重复序列组成;另一类(GhPRPL)与典型的PRPs结构不同,这个蛋白质的N端为亲水序列,GhPRPL在靠近C端有8个5肽(类似PPKKE)的重复基序,与典型PRPs所含有的重复序列PPVYK非常相似.实时RT-PCR(Real-time RT-PCR)分析表明,GhPRP3和GhPRP5在10dpa纤维中特异表达,而GhPRPL在子叶中优势表达.GhPRP4和GhPRP6在所分析的组织中都有表达,GhPRP4mRNA在下胚轴中最丰富,在花药中次之,而GhPRP6在10dpa纤维中表达最强,在10dpa胚珠中次之.此外,GhPRP3,GhPRP5基因表达受纤维发育调节,表明它们可能在棉纤维发育中起重要作用.