Cloning of a down-regulated gene encoding small GTP binding protein in hybrid wheat

Previous studies showed that differential gene expression between wheathybrids and their parents was responsible for the heterosis. To provide an insight into the molecular basis of wheat heterosis, one cDNA, designated TaRab, was identified from the cDNA library of wheat seedling leaves. The sequence comparison in GenBank revealed that TaRab is homologous to a group of genes encoding Rab-GTP binding protein. Semi-quantitative RT-PCR analysis indicated that TaRab was expressed in all plant tissues examined, but at slightly higher level in leaves. Further analysis exhibited that TaRab displayed lower expression in hybrid than in its patents in both roots and leaves, which was in agreement with the original results of suppression subtractive hybridization. TaRab was located on chromosome 7B and C-7DS5-0.36 by in silico mapping. The relationship between differential expression of TaRab and the molecular basis of wheat heterosis was also discussed.     

Cloning and expression profiles of 15 genes encoding WRKY transcription factor in wheat (Triticum aestivem L.)

WRKY proteins are involved in various physiological processes, including biotic and abiotic stress responses, hormone responses and development. However, no systematic identification, expression and function analysis of WRKY genes in wheat were reported. In this study, we isolated 15 wheat cDNAs with complete open reading frame (ORF) encoding putative WRKY proteins using in silico cloning. Phylogenetic analysis indicated that the 15 wheat WRKY genes belonged to three major WRKY groups. Expression analysis revealed that most genes expressed drastically in leaf, except TaWRKY10 which expressed in crown intensively. Four genes were strongly up-regulated with the senescence of leaves. Eight genes were responsive to low temperature, high temperature, NaCl or PEG treatment. Moreover, differential expression patterns were also observed between wheat hybrid and its parents, and some genes were more responsive to PEG treatment in the hybrid. These results demonstrated that wheat WRKY genes are involved in leaf senescing and abiotic stresses. And the changed expression of these WRKY genes in hybrid might contribute to the heterosis by improving the stress tolerance in hybrids.     

Cloning and expression profiles of 15 genes encoding WRKY transcription factor in wheat （Triticum aestivem L.）

WRKY proteins are involved in various physiological processes, including biotic and abiotic stress responses, hormone responses and development. However, no systematic identification, expression and function analysis of WRKY genes in wheat were reported. In this study, we isolated 15 wheat cDNAs with complete open reading frame （ORF） encoding putative WRKY proteins using in silico cloning. Phylogenetic analysis indicated that the 15 wheat WRKY genes belonged to three major WRKY groups. Expression analysis revealed that most genes expressed drastically in leaf, except Ta WRKYIO which expressed in crown intensively. Four genes were strongly up-regulated with the senescence of leaves. Eight genes were responsive to low temperature, high temperature, NaCl or PEG treatment. Moreover, differential expression patterns were also observed between wheat hybrid and its parents, and some genes were more responsive to PEG treatment in the hybrid. These results demonstrated that wheat WRKY genes are involved in leaf senescing and abiotic stresses. And the changed expression of these WRKY genes in hybrid might contribute to the heterosis by improving the stress tolerance in hybrids.     

Cloning and expression pro?les of 15 genes encoding WRKY transcription factor in wheat (Triticum aestivem L.)

WRKY proteins are involved in various physiological processes, including biotic and abiotic stress responses, hormone responses and development. However, no systematic identi?cation, expression and function analysis of WRKY genes in wheat were reported. In this study, we isolated 15 wheat cDNAs with complete open reading frame (ORF) encoding putative WRKY proteins using in silico cloning. Phylogenetic analysis indicated that the 15 wheat WRKY genes belonged to three major WRKY groups. Expression analysis revealed that most genes expressed drastically in leaf, except TaWRKY10 which expressed in crown intensively. Four genes were strongly up-regulated with the senescence of leaves. Eight genes were responsive to low temperature, high temperature, NaCl or PEG treatment. Moreover, differential expression patterns were also observed between wheat hybrid and its parents, and some genes were more responsive to PEG treatment in the hybrid. These results demonstrated that wheat WRKY genes are involved in leaf senescing and abiotic stresses. And the changed expression of these WRKY genes in hybrid might contribute to the heterosis by improving the stress tolerance in hybrids. 2007 National Natural Science Foundation of China and Chinese Academy of Sciences. Published by Elsevier Limited and Science in China Press. All rights reserved.     

Cloning and expression pro?les of 15 genes encoding WRKY transcription factor in wheat (Triticum aestivem L.)

WRKY proteins are involved in various physiological processes, including biotic and abiotic stress responses, hormone responses and development. However, no systematic identi?cation, expression and function analysis of WRKY genes in wheat were reported. In this study, we isolated 15 wheat cDNAs with complete open reading frame (ORF) encoding putative WRKY proteins using in silico cloning. Phylogenetic analysis indicated that the 15 wheat WRKY genes belonged to three major WRKY groups. Expression analysis revealed that most genes expressed drastically in leaf, except TaWRKY10 which expressed in crown intensively. Four genes were strongly up-regulated with the senescence of leaves. Eight genes were responsive to low temperature, high temperature, NaCl or PEG treatment. Moreover, differential expression patterns were also observed between wheat hybrid and its parents, and some genes were more responsive to PEG treatment in the hybrid. These results demonstrated that wheat WRKY genes are involved in leaf senescing and abiotic stresses. And the changed expression of these WRKY genes in hybrid might contribute to the heterosis by improving the stress tolerance in hybrids. 2007 National Natural Science Foundation of China and Chinese Academy of Sciences. Published by Elsevier Limited and Science in China Press. All rights reserved.     

Relationship between differ- ential gene expression pat- terns in functional leaves of maize (Zea mays L.) at milk filling stage and heterosis using cDNA-AFLP

The genetic mechanism of heterosis has been one of the most challenging subjects in life science since the 20th century. However, because of the complexity of its genetic basis and the limitations of research methods and means, there was no substantial progress in the research of heterosis from the beginning of the 20th century to the 1990s. The development in molecular biology and bio- technology, especially that in quantitative trait loci (QTL) mapping methods, has made it possible to resea…     

Relationship between differential gene expression patterns in functional leaves of maize (<Emphasis Type="Italic">Zea mays</Emphasis> L.) at milk filling stage and heterosis using cDNA-AFLP

To understand the molecular mechanism of maize heterosis ,differential gene expression patterns in the functional leaves of 35 maize hybrids relative to their parents involving 10 elite inbreds at milk filling stage were analyzed hy using cDNA-AFLP,the correlation analyses of various differential expression patterns with the performance and heterosis of main maize agronomic traits were evaluated.The main results were as follows:For uniparental specific expression ,significant positive correlations were detected with the performance of seed weight per ear and 100-seed weight at 0.01 and 0.05 probability levels respectively.For biparental specific expression ,significant negative correlations were detected with the performance of ear diameter and seed weight per ear at 0.01 probability level .For uniparental specific expression ,significant positive correlations were detected with the heterosis of ear diameter and seed weight per ear at 0.01 and 0.05 probability levls rspectively,For biparental specific expression .significant negtive correlation was detected with theheterosis of ear diameter at 0.05 probability level ,However,for F1-spectific expression,for fragments detected only in one parent and F1,and for fragments detected only in two parents or only in F1,no significant correlation was detected with the performance or heterosis of all agronomic traits surveyed.     

The relationship of differential expression of genes in GA biosynthesis and response pathways with heterosis of plant height in a wheat diallel cross

Heterosis in internode elongation and plant height is commonly observed in hybrid plants, but the molecular basis for the increased internode elongation in hybrids is unknown. In this study, midparent heterosis in plant height was determined in a wheat diallel cross involving 16 hybrids and 8 parents, and real-time PCR was used to analyze alterations in gene expression between hybrids and parents. Significant heterosis of plant height and the first internode in length were observed for all 16 hybrids, but the magnitude of heterosis was variable for different cross combinations. Analysis revealed that the heterosis of the first internode was significantly correlated to that of plant height （r = 0.56, P 〈 0.05）, suggesting that the increased elongation of the first internode is the major contributor to the heterosis in plant height. Real-time PCR analysis exhibited that significant difference in heterosis of gene ex- pression was observed among all cross combinations. Moreover, heterosis of the first internode in length was correlated significantly and positively with expression heterosis of KS, GA3ox2-1, GA20ox2, GA20ox1D, GA-MYB and GID1-1, but significantly and negatively with expression heterosis of GAI and GA2ox-1, which is consistent with our recently proposed model of GAs and heterosis in wheat plant height, suggesting the alteration of GA biosynthesis and response pathways might be responsible for the observed heterosis in plant height.     

高丹草及其亲本种子胚差异蛋白质组学分析

 高丹草是综合高粱和苏丹草双亲优良性状的一年生禾本科饲草,其杂种优势特别明显,但杂种优势形成机理还不明确。为了揭示高丹草杂种优势形成机理,本研究以杂种高丹草及其亲本的成熟胚为试材,利用Label free结合质谱技术,采用生物信息学分析方法在蛋白质组学水平进行研究。研究结果鉴定出差异蛋白124个,其中加性积累蛋白48个,占差异蛋白总数的38.71%,加性积累蛋白中上调蛋白19个,下调蛋白29个。鉴定出非加性积累蛋白为76个,占差异蛋白总数的61.29%,非加性积累蛋白的表达模式以超高亲表达所占比例最大（29个）,其次是偏高亲表达模式（18个）,偏低亲表达模式次之（14个）,另外还有超低亲表达模式（10个）,以及不属于该四种表达模式蛋白5个,因此,加性积累蛋白在高丹草成熟胚杂种优势形成上起主导作用。加性与非加性积累蛋白涉及多个功能组,主要是胁迫响应、碳水化合物代谢、转录调控、发育调控、信号转导、蛋白质代谢等功能类别。     

Analysis of gene expression patterns with cDNA microarray during late stage of spermatogenesis in mice

The differentiation process of round spermatids to spermatozoa during the late stage of spermatogenesis is called spermiogenesis. To explore spermiogenesis-related genes, cDNA microarray was used to study expression patterns of 1176 genes in pachytene spermatocytes, round spermatids and elongating spermatids of Balb/c mice. The results showed that 208 genes were detected in all the three cell types. Most of them were down-regulated from pachytene spermatocytes to round spermatids and elongating spermatids. However, up-regulation of 7 genes expression in round spermatids and 3 genes in elongating spermatids were found. Expression of 7 differentially expressed genes in cDNA arrays was further confirmed by semi-quantitative RT-PCR study. The RT-PCR results indicated that the expression of 6 genes was consistent with that in cDNA arrays, only one gene did not show differential expression by RT-PCR. These results may provide important clues for studying of expression, regulation, and function of spermiogenesis-related genes.     

新澄杂种西瓜及其亲本的同工酶分析

对良种西瓜“新澄”杂种及其亲本的酯酶、过氧化物酶同工酶进行分析研究的结果表明,杂种与其亲本的同工酶酶谱有显著差异,杂种除了具有双亲的“互补酶带”外,还出现双亲所没有的“杂种酶带”;同时发现杂种优势与酶谱的变化有密切相关.应用同工酶分析法鉴定这种价值昂贵的杂种种子的纯度,有一定的经济价值.     

用差异显示技术分离空心莲子草抗旱相关基因

采用mRNA差异显示技术,分离空心莲子草在干旱胁迫1 d后差异表达的基因,获得139个基因片段.经过Reverse Northern检测,初步证实有两个片段受干旱诱导表达上调.对其中一个片断克隆测序并进行核甘酸序列比对,显示与其他基因同源性都很低,表明可能是新的基因.半定量PCR技术证实该基因受干旱诱导表达上调.     

玉米大斑病菌StNPS6基因缺失突变体的转录组与蛋白质组差异表达分析

用T-DNA插入法构建一个玉米大斑病菌突变体库, 并筛选到一株致病力明显下降的突变体. 该突变体T DNA插入位点为非核糖体肽合成酶基因6（StNPS6基因）的上游启动子区. 先敲除StNPS6基因, 再对StNPS6基因敲除突变体和野生型进行转录组差异表达分析及蛋白质组差异表达分析. 结果表明: 在1 767个差异表达基因中的上调表达基因903个, 下调表达基因864个; 在突变体中鉴定30个差异表达蛋白质中的上调表达蛋白质8个, 下调表达蛋白质22个.     

Gene expression profiles of the developing human retina

Retinaplaysimportantrolesintheperception,proc-essandtransmissionofvisualsignalsandthefunctionsoftheretinadepend,toalargeextent,onitshighlyorganizedstructure.During3—6weeksinhumanembryogenesis,theneuralectodermgrowsoutfromthediencephalonstoformtheopticvesicleandtheninvaginatestoformtheopticcup.Theouterlayeroftheopticcupbecomesthenon-neuralretinalpigmentepithelium(RPE)andtheinnerlayerbecomestheneuralretina.RPEcellsproliferateslowlyandappeardifferentiatedandpigmentedasearlyas6—8weeksandremain…