中亚滨藜甜菜碱醛脱氢酶基因的表达特性

根据已发表的几种植物的甜菜碱醛脱氢酶（BADH）基因的同源保守区设计了一对兼并引物,通过RT-PCR方法从中亚滨藜中扩增出BADH基因的近5′端序列,共395bp,与菠菜、山菠菜、甜菜、千穗谷、大麦的BADHcDNA相应片段的同源性较高。以此片段为探针,对中亚滨藜的基因组进行Southern杂交分析,证明该基因可能是单拷贝的。Northern印迹杂交结果表明NaCl250mmol/L处理的植株的BADHmRNA水平比对照植株约高2倍,说明中亚滨藜中BADH基因的表达受盐诱导。     

盐生植物盐爪爪甜菜碱醛脱氢酶基因的克隆及在盐胁迫下的BADH 基因的表达

根据已发表的几种藜科植物甜菜碱醛脱氢酶(BADH) 基因的同源保守区设计了一对引物, 采用RT-PCR 方法从盐生植物盐爪爪( Kalidium foliatum) 中扩增出BADH 基因的1 个开放阅读框架, 其核苷酸序列长1 503 bp , 推测的氨基酸序列全长为500 个氨基酸残基。核苷酸序列与藜科几种盐生植物如滨藜、碱蓬、菠菜、山菠菜和甜菜等的同源性为81% , 与甜土植物水稻的同源性为69%。氨基酸序列与以上两类植物(盐生植物和甜土植物) 的同源性比对为80% 和71% , 说明BADH 基因在藜科盐生植物中是一种较高保守的基因。BADH 基因编码的多肽在高等植物中行使重要的功能。用不同浓度的NaCl 胁迫处理盐爪爪植株, BADH mRNA 的表达水平比对照植株高, 说明盐爪爪BADH 基因的表达受盐诱导, 间接说明甜菜碱醛脱氢酶催化合成的甜菜碱作为渗透调节的小分子物质, 它的积累与盐胁迫存在紧密关联, 本研究为进一步从生理和分子水平阐明盐爪爪的耐盐机制提供一定的参考。     

盐生植物盐爪爪甜菜碱醛脱氢酶基因的克隆及在盐胁迫下的BADH基因的表达

根据已发表的几种藜科植物甜菜碱醛脱氢酶(BADH)基因的同源保守区设计了一对引物,采用RT-PCR方法从盐生植物盐爪爪(Kalidium foliatum)中扩增出BADH基因的1个开放阅读框架,其核苷酸序列长1503bp,推测的氨基酸序列全长为500个氨基酸残基。核苷酸序列与藜科几种盐生植物如滨藜、碱蓬、菠菜、山菠菜和甜菜等的同源性为81%,与甜土植物水稻的同源性为69%。氨基酸序列与以上两类植物(盐生植物和甜土植物)的同源性比对为80%和71%,说明BADH基因在藜科盐生植物中是一种较高保守的基因。BADH基因编码的多肽在高等植物中行使重要的功能。用不同浓度的NaCl胁迫处理盐爪爪植株,BADHmRNA的表达水平比对照植株高,说明盐爪爪BADH基因的表达受盐诱导,间接说明甜菜碱醛脱氢酶催化合成的甜菜碱作为渗透调节的小分子物质,它的积累与盐胁迫存在紧密关联,本研究为进一步从生理和分子水平阐明盐爪爪的耐盐机制提供一定的参考。     

盐穗木甜菜碱醛脱氢酶基因（BADH）的克隆及其在盐胁迫下的表达分析

根据我们实验室已发表的植物甜菜碱醛脱氢酶基因（BADH）的同源保守区设计引物,通过RT—PCR扩增获得了由1503个核苷酸组成的盐穗木BADH基因开放阅读框,推测该基因编码500个氨基酸,分子量约为54．49kDa的多肽。推测的盐穗木BADH氨基酸序列中包含一段甜菜碱醛脱氢酶中高度保守的十肽序列（VTLELGGKSP）以及与酶功能有关的半胱氨酸残基（Cys）。序列比对结果显示,盐穗木BADH与盐地碱蓬、中亚滨藜、盐爪爪以及菠菜等的核苷酸序列同源性在81％以上,与水稻的同源性也达到68％。半定量RT—PCR分析结果表明,盐穗木BADH基因的表达受盐胁迫诱导,推测BADH可能与盐穗木具有较强的耐盐能力有关。     

中亚滨藜甜菜碱醛脱氢酶基因的表达特性

根据已发表的几种植物的甜菜碱醛脱氢酶（BADH）基因的同源保守区设计了一对兼并引物,通过RT-PCR方法从中亚滨藜中扩增出BADH基因的近5′端序列,共395bp,与菠菜、山菠菜、甜菜、千穗谷、大麦的BADHcDNA相应片段的同源性较高,以此片段为探针,对中亚滨藜的基因组进行Southern杂交分析,证明该基因可能是单拷贝的。Northern印迹杂交结果表明：NaCl250mmol/L处理的植株的BADHmRNA水平比对照植株约高2倍。说明中亚滨藜中BADH基因的表达受盐诱导。     

甘菊BADH基因cDNA的克隆及在盐胁迫下的表达

利用PCR、RT—PCR和PCR—RACE技术,从菊科植物甘菊（Dendranthema lavandulifolium）中克隆到2个甜菜碱醛脱氢酶（betaine aldehyde dehydrogenase,BADH）基因的同源基因,分别命名为DlBADH1和DlBADH2,GenBank登录号分别为DQ011151和DQ011152。DlBADH1的cDNA全长1821bp,其开放阅读框编码503个氨基酸的蛋白质;DlBADH2全长1918bp,编码506个氨基酸的蛋白质。两个基因核苷酸序列的同源性为97％,推导的氨基酸序列的同源性为98％。与已发表的其它植物BADH基因氨基酸序列的同源性在64％以上。在推导的氨基酸序列中,均含有醛脱氢酶所具有的高度保守的十肽（VTLELGGKSP）以及与酶功能有关的半胱氨酸残基（C）。在推导的氨基酸序列的系统关系中,甘菊位于其它双子叶植物和单子叶植物之间,与其植物分类的系统关系相吻合。RT—PCR—Southern半定量表达分析表明,甘菊BADH基因家族中存在表达受盐诱导的成员。     

甘菊BADH基因cDNA的克隆及在盐胁迫下的表达

利用PCR、RT-PCR和PCR-RACE技术,从菊科植物甘菊(Dendranthema lavandulifolium)中克隆到2个甜菜碱醛脱氢酶(betaine aldehyde dehydrogenase,BADH)基因的同源基因,分别命名为DlBADH1和DlBADH2,GenBank登录号分别为DQ011151和DQ011152.DlBADH1的cDNA全长1821 bp,其开放阅读框编码503个氨基酸的蛋白质;DlBADH2全长1918 bp,编码506个氨基酸的蛋白质.两个基因核苷酸序列的同源性为97%,推导的氨基酸序列的同源性为98%.与已发表的其它植物BADH基因氨基酸序列的同源性在64%以上.在推导的氨基酸序列中,均含有醛脱氢酶所具有的高度保守的十肽(VTLELGGKSP)以及与酶功能有关的半胱氨酸残基(C).在推导的氨基酸序列的系统关系中,甘菊位于其它双子叶植物和单子叶植物之间,与其植物分类的系统关系相吻合.RT-PCR-Southern半定量表达分析表明,甘菊BADH基因家族中存在表达受盐诱导的成员.     

菠菜甜菜碱醛脱氢酶基因的克隆和序列分析

以耐盐的菠菜mRNA为模板,经反转录合成甜菜碱醛脱氢酶(BADH)基因第一链cDNA。在人工合成的两端引物引导下,通过多聚酶链式反应(PCR),扩增获得双链cDNA。把重组有BADH基因的pUC19转化至E.coli DH5α菌株,亚克隆后测定了基因的全序列。所得到的BADH基因全长序列为1491bp,编码497个氨基酸。与文献报道的相比较,核苷酸序列同源性99.8％,氨基酸序列同源性达99.6％。在此基础上,构建了BADH基因的高等植物表达载体。     

甘菊BADH基因cDNA的克隆及在盐胁迫下的表达

利用PCR、RT-PCR和PCR-RACE技术,从菊科植物甘菊(Dendranthema lavandulifolium)中克隆到2个甜菜碱醛脱氢酶(betaine aldehyde dehydrogenase,BADH)基因的同源基因,分别命名为DlBADH1和DlBADH2,GenBank登录号分别为DQ011151和DQ011152。DlBADH1的cDNA全长1821 bp,其开放阅读框编码503个氨基酸的蛋白质;DlBADH2全长1918 bp,编码506个氨基酸的蛋白质。两个基因核苷酸序列的同源性为97%,推导的氨基酸序列的同源性为98%。与已发表的其它植物BADH基因氨基酸序列的同源性在64%以上。在推导的氨基酸序列中,均含有醛脱氢酶所具有的高度保守的十肽(VTLELGGKSP)以及与酶功能有关的半胱氨酸残基(C)。在推导的氨基酸序列的系统关系中,甘菊位于其它双子叶植物和单子叶植物之间,与其植物分类的系统关系相吻合。RT-PCR-Southern半定量表达分析表明,甘菊BADH基因家族中存在表达受盐诱导的成员。     

梭梭甜菜碱醛脱氢酶基因克隆及序列分析

采用RT-PCR、RACE等方法从超旱生、耐盐植物梭梭(Haloxylon ammodendron)中扩增出BADH基因的cDNA序列(命名为HaBADH),其开放阅读框为1 503 bp,推测的氨基酸序列全长为500个氨基酸残基,并含有醛脱氢酶所具有的高度保守的十肽(VTLELGGKSP)以及与酶功能有关的半胱氨酸残基(C).其核苷酸序列与藜科几种盐生植物如盐爪爪(Kalidium foliatum)、中亚滨藜(Atriplex centralasiatica)、三角叶滨藜(Atriplex triangularis)、菠菜(Spinacia oleracea)、山菠菜(Atriplex hortensis)和甜菜(Beta vulgaris)等的相似性均在85%以上,推导编码蛋白的氨基酸序列一致性均在87%以上,表明BADH基因在藜科植物中是一种比较保守的基因.研究结果为进一步从分子水平探明梭梭的抗旱、耐盐机制,挖掘并利用植物抗逆基因奠定基础.     

Expression of betaine aldehyde dehydrogenase gene and salinity tolerance in rice transgenic plants

Betaine as one of osmolytes plays an important role in osmoregulation of most high plants. Betaine aldehyde dehydrogenase C BADH) is the second enzyme involved in betaine biosynthesis. The BADH gene from a halophite, Atriplex hortensis, was transformed into rice cultivars by bombarment method. Totally 192 transgenic rice plants were obtained and most of them had higher salt tolerance than controls. Among transgenic plants transplanted in the saline pool containing 0.5% NaCl in a greenhouse, 22 survived, 13 of which set seeds, and the frequency of seed setting was very low, only 10% . But the controls could not grow under the same condition. The results of BADH ac-tivity assay and Northern blot showed that the BADH gene was integrated into chromosomes of transgenic plants and expressed.     

甜菜碱醛脱氢酶(BADH)基因转化小麦及其表达

采用基因枪法将山菠菜甜菜碱醛脱氢酶 (BADH)基因导入小麦 (TriticumaestivumL .)品种 ,并且得以表达。该基因由玉米Ubi1启动子控制。在盐胁迫条件下 ,多数转基因植株叶片的BADH活性比受体亲本提高 1～ 3倍 ,部分植株相对电导率比亲本明显低 ,表明转基因植株的细胞膜在胁迫时有受损较轻倾向。PCR和Southern杂交分析证实外源BADH基因已插入小麦基因组 ,平均转化频率为 4.1%。     

盐生植物--中亚滨藜的研究及用途

通过对中亚滨藜的生长情况观察,以及人工栽培试验数据分析,发现中亚滨藜能够改良土壤,幼苗含有较高的叶蛋白,有很高饲用价值,生物产量巨大,果实入药,有很大的开发潜力.     

野榆钱菠菜（Atriplex aucheri）的种子多型性及生态型

对野榆钱菠菜的花、果实及种子进行了观察,表明野榆钱菠菜具有1种雄花、2种雌花,却产生3种果实和种子。这3种种子在形状、大小、颜色、着生方式及包被其苞片的大小上均有差异。且该种植物种内的生态型在生长习性、结实率和种子类型上都存在很大的差异。     

A betaine aldehyde dehydrogenase gene in quinoa (<Emphasis Type="Italic">Chenopodium quinoa</Emphasis>): structure,phylogeny, and expression pattern

Betaine aldehyde dehydrogenase (BADH) is widely considered as a key enzyme in glycine betaine metabolism in higher plants. Several paralogous genes encoding different isozymes of BADH have been identified and characterized in some plants; however, until now, only limited information is available about BADH genes in quinoa (Chenopodium quinoa). Here, we report the molecular cloning, structural organization, phylogenetic evolution, and expression profile of a BADH gene (CqBADH1) from quinoa. The translated putative CqBADH1 protein included five conserved features of the ALDH Family 10. Comparisons between the cDNA and genomic sequences revealed that the CqBADH1 gene contained 15 exons and 14 introns. Comparative screening of introns in homologous genes demonstrated that the number and position of the BADH introns were highly conserved among the BADH genes in Amaranthaceae plants and in other more distantly related plant species. A phylogenetic analysis showed that CqBADH1 had the closest relationship with a protein from Atriplex canescens and belonged to the ALDH10 family. Expression profile analyses indicated that CqBADH1 was expressed only in root, and showed time-dependent expression profiles under NaCl-stress condition. Moreover, in quinoa, NaCl stress led to increased levels of CqBADH1 mRNA accompanied by the accumulation of glycine betaine. This is the first study to describe a BADH gene in quinoa.     

Genetic structure of Atriplex halimus populations in the Mediterranean Basin

BACKGROUND AND AIMS: The saltbush Atriplex halimus is a chenopodiaceous plant well adapted to dry saline habitats and widely distributed in the Mediterranean Basin. A study was carried out to analyse the genetic diversity of A. halimus at the level of the Mediterranean Basin. METHODS: To assess the intra- and interpopulational variation of A. halimus a total of 51 populations and six plants per populations was analysed with the RAPD-PCR technique. For the study of the phylogeny of the populations, 21 samples of A. halimus and seven samples of other species of Atriplex were analysed by the sequencing of the ITS (internal transcribed spacer) region of the ribosomal DNA. KEY RESULTS: The AMOVA analysis of the RAPD results showed that populations were divided into two discrete genetic groups, as the variation among groups accounted for 54.36 % of the total variance of the collection. At the same time, the intrapopulational diversity was high, as 301 out of 306 plants analysed constituted an individual RAPD haplotype. The sequencing of the ITS region also showed a significant separation of the two genetic groups, with a genetic distance of 0.023 nucleotide substitutions per site. Using A. breweri, A. canescens, A. glauca and A. prostrata as outgroups in the phylogenetic analysis, A. breweri and A. canescens are the species closest to A. halimus from this group, while A. prostrata is the most distant. CONCLUSIONS: The present work indicates that two genetic groups of A. halimus can be distinguished after analysing the genetic diversity of 51 populations from ten countries in the Mediterranean Basin.