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111.
叶色是与作物的光合速率及产量紧密相关的重要性状,利用叶色突变体研究叶绿体的发育过程及调控网络,有助于揭示叶色形成的机制。本研究在农杆菌介导的大麦幼胚遗传转化过程中,获得一个具有条纹叶片的突变体(msal),该突变株具有条纹白化的叶片、茎秆,叶鞘、幼穗及幼种,其叶绿素和类胡萝卜素含量均下降。叶绿体超微结构观察显示条纹叶片突变体细胞的叶绿体数量变少,呈狭长型,结构不完整。转录组分析表明在突变体中有1004个差异基因,其中388个表达量下调,609个表达量上调。GO富集分析显示细胞组份"叶绿体"的富集频率最高,为23.0%,P值为5.74e-07,表明"叶绿体"在转录水平上发生了改变。62个与叶绿体发育相关的差异基因在突变体中表达量均为上调,而与类胡萝卜素合成相关的差异基因表达量下调。我们推测该突变体抑制了类胡萝卜素的合成,影响了叶绿体发育,而作为补偿机制激活了叶绿体相关发育基因的表达。 相似文献
112.
113.
Hironori Katayama Shiho Adachi Toshiya Yamamoto Chiyomi Uematsu 《Genetic Resources and Crop Evolution》2007,54(7):1573-1585
Iwateyamanashi (Pyrus ussuriensis var. aromatica) is one of the Pyrus species which grows wild in Japan. The number of Iwateyamanashi trees has been decreasing, so conservation and evaluation
is urgently needed. Over 500 accessions of Pyrus species collected from Iwate in northern Tohoku region are maintained at Kobe University as an Iwateyamanashi germplasm collection.
In order to investigate the genetic diversity, five SSR (simple sequence repeat) markers, developed from Japanese and European
pear were examined for 86 Pyrus individuals including 58 accessions from Iwate. These SSR loci could discriminate between all the Iwate accessions except
for 10 that bear seedless fruit, as well as determine the genetic diversity in Iwateyamanashi germplasms. High levels of variation
were detected in 41 alleles and the mean observed heterozygosity across 5 loci was 0.50 for the Iwate accessions. Seedless
accessions sharing identical SSR genotype with the local pear variety “Iwatetanenashi” were supposed to have been propagated
vegetatively via grafting. In an UPGMA phenogram, Japanese pear varieties (P. pyrifolia) were clustered into two groups with some Iwate accessions including seedless ones. Another 38 Iwate accessions were not
clustered clearly, and there was no clear relationship between these accessions and geographical distribution or morphological
characters. Allele frequency revealed that the Iwate accessions were genetically more divergent than the Japanese pear varieties.
Most Japanese pears possessed a 219 bp deletion at a spacer region between the accD and psaI genes in the chloroplast DNA (cpDNA), but other Pyrus species and two Iwateyamanashi trees did not. In the Iwate accessions, 79.3% had a deletion type cpDNA and others had a standard
type cpDNA without deletion. These results are indicative of the wide range of genetic diversity in the Iwate accessions which
include Japanese pear varieties. A combination of SSR and cpDNA analyses revealed high heterogeneity in Iwateyamanashi and
coexistence of Iwateyamanashi and hybrid progeny with P. pyrifolia. These could be reasons for the wide range of continuous morphological variation described previously. 相似文献
114.
Ali M. Missaoui Andrew H. Paterson Joseph H. Bouton 《Genetic Resources and Crop Evolution》2006,53(6):1291-1302
Information regarding the amount of genetic diversity is necessary to enhance the effectiveness of breeding programs and germplasm conservation efforts. Genetic variation between 21 switchgrass genotypes randomly selected from two lowland (‘Alamo’ and ‘Kanlow’) and one upland (‘Summer’) synthetic cultivars were estimated using restriction fragment length polymorphism (RFLP) markers. Comparison of 85 RFLP loci revealed 92% polymorphism between at least two genotypes from the upland and lowland ecotypes. Within ecotypes, the upland genotypes showed higher polymorphism than lowland genotypes (64% vs. 56%). ‘Kanlow’ had a lower percent of polymorphic loci than ‘Alamo’ (52% vs. 60%). Jaccard distances revealed higher genetic diversity between upland and lowland ecotypes than between genotypes within each ecotype. Hierarchical cluster analysis using Ward's minimum variance grouped the genotypes into two major clusters, one representing the upland group and the other the lowland group. Phylogenetic analysis of chloroplast non-coding region trnL (UAA) intron sequences from 34 switchgrass accessions (6 upland cultivars, 2 lowland cultivars, and 26 accessions of unknown affiliation) produced a neighbor-joining dendrogram comprised of two major clusters with 99% bootstrap support. All accessions grouped in the same cluster with the lowland cultivars (‘Alamo’ and ‘Kanlow’) had a deletion of 49 nucleotides. Phenotypic identification of greenhouse-grown plants showed that all accessions with the deletion are of the lowland type. The deletion in trnL (UAA) sequences appears to be specific to lowland accessions and should be useful as a DNA marker for the classification of upland and lowland germplasm. 相似文献
115.
由核基因编码的叶绿体前体蛋白能否正确定向和转运到叶绿体,对叶绿体的功能十分重要。采用酵母双杂交方法,筛选豌豆的cDNA表达文库,分析检测与Rubisco小亚基前体蛋白(preSSU)相互作用并参与其调控的蛋白。结果表明,共有6种不同类型的蛋白与preSSU互作,分别为组氨酸蛋白激酶基因、转运蛋白复合体、转录和翻译相关蛋白及复合体、信号传导相关基因和光合合成相关基因。通过与相关蛋白的相互作用,preSSU也许参与了植物抗逆信号传导系统,并在植物的生长发育、成熟和衰老过程中起重要作用。 相似文献
116.
小麦突变体返白系返白阶段叶绿体超微结构变化研究 总被引:3,自引:0,他引:3
分别采取返白系返白前期(全绿苗)、返白中期(全白苗)和复绿苗5个不同叶龄叶片,通过电镜系统观察了各叶龄叶片的叶绿体超微结构,结果表明,返白过程中,返白系幼叶中的幼龄质体发育停滞于前质体阶段,随着叶龄增加,已发育的质体体积虽有一定程度增大,但质体内部结构不能形成甚至退化;复绿过程中,幼叶中的质体恢复发育,叶龄较大的叶片中(如全卷叶)存在着发育程度不同的质体,小的质体可能恢复发育,最终导致叶片复绿,而较大的质体则空化。说明返白过程中幼龄质体发育停滞,或已发育的部分质体内部结构退化是叶片白化的原因,停滞发育的前质体恢复发育是复绿的主要细胞学特征。 相似文献
117.
以高产杂交稻两优培九和常规杂交稻汕优63为材料,研究10℃夜间低温处理对水稻幼苗叶绿体自发荧光强度及抗氧化系统的影响。与同时期的常温对照相比,两优培九的SOD、GR、CAT、POD酶活性的上升幅度要强于汕优63,而汕优63的GSH、ASA含量的上升幅度要强于两优培九。两优培九的O2-和MDA的积累少,叶绿体自发荧光强度降低程度小于汕优63。表明两优培九幼苗的抗冷性优于汕优63。胁迫后期,两优培九中一些保护酶类活性低于对照,O2-产生速率和MDA含量高于对照,表明此时活性氧清除系统的平衡已被破坏。 相似文献
118.
Wen Xu Feng ZhangBeibei Lu Xiaoyan CaiBeiwei Hou Zhenyu FengXiaoyu Ding 《Scientia Horticulturae》2011
Nine pairs of polymorphic chloroplast microsatellite primers were developed for Dendrobium officinale Kimura et Migo, an endangered herb. Levels of polymorphism were tested across a total of 55 individuals from four natural populations (12–15 individuals per population). Allele numbers varied from two to four per locus, while the number of haplotypes ranged from four to six per population. Transferability of the nine polymorphic chloroplast microsatellite primers was checked on an additional set of 51 Dendrobium individuals (belonging to 17 different species). Three markers could be transferable to all the species tested, while the remaining six markers successfully cross-amplified in most species tested. Moreover, polymorphism of the nine chloroplast microsatellite primers was tested across Dendrobium moniliforme (L.) Sw. and Dendrobium loddigesii Rolfe. All of them were polymorphic in D. moniliforme, while seven of which were polymorphic in D. loddigesii. These polymorphic chloroplast microsatellite primers developed for D. officinale will be a useful tool for the study of genetic diversity, population genetic structure, evolution of D. officinale and establishment of effective conservation strategies. 相似文献
119.
双价抗虫基因共转化烟草叶绿体的研究 总被引:5,自引:0,他引:5
分别构建苏云金芽孢杆菌晶体毒蛋白基因 [BtCryIA(C) ]和水稻巯基蛋白酶基因 (Oryzacystatin ,OC)叶绿体转化载体 ,其中Bt基因叶绿体转化载体以烟草叶绿体基因trnH psbA trnK为同源片段 ,以水稻 (OryzasativaL .)叶绿体 psbA基因启动子和终止子为调控基因 ;OC基因叶绿体表达载体以烟草叶绿体基因片段 psbA ORF5 12为同源片段 ,以烟草叶绿体 16S启动子和终止子为调控基因 ;两载体均以壮观霉素抗性基因 (aadA)为筛选基因。利用基因枪方法 ,共转化烟草叶片 ,获得壮观霉素抗性植株。经Southern、Western检测、表达蛋白活性测定证明 ,双价抗虫基因己整合到烟草叶绿体中并得到表达。转基因植株抗棉铃虫试验表明 ,转基因植株具有显著杀虫活性 相似文献
120.
低钾胁迫对玉米自交系苗期叶绿体结构及光合响应影响 总被引:2,自引:0,他引:2
研究低钾胁迫对玉米苗期叶绿体结构及光合响应的影响。玉米自交系种子A(不耐低钾)和B(耐低钾)以3个不同钾离子浓度(5μmol/L,100μmol/L,1000μmol/L)进行液体培养,连续培养50天。测定其叶绿体形态结构,光强、CO2、温度对光合响应曲线。低钾处理初期,B叶绿体基粒数多于A,并且片层密度加厚;低钾处理后期,B与A叶绿体结构与形态趋向一致。B的CO2饱和点上升、光饱和点上升,CO2同化能力增加及光能利用率、温度效应增加。低钾胁迫时,耐低钾自交系B通过叶绿体基粒数增多,净光合速率升高,CO2饱和点、光饱和点上升,CO2同化能力及光能利用率、温度效应增加,提高其光合作用,从而适应低钾胁迫。 相似文献