首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到17条相似文献,搜索用时 218 毫秒
1.
莪术CPD染色和45S rDNA荧光原位杂交核型分析   总被引:1,自引:0,他引:1  
为了对莪术[Curcuma zedoaria (Christm.) Roscoe]的染色体进行识别并对该物种基因组的结构及进化进行初步研究,利用改进的火焰干燥法及荧光原位杂交技术,对莪术中期染色体的长度,着丝粒的位置及随体的数目进行分析。PI和DAPI组合(CPD)染色后和相继的45S rDNA探针荧光原位杂交结果显示,莪术具有五对45S rDNA位点,三对位于8,22,31号染色体末端的CPD带区,二对位于4,30号染色体的短臂上。第五号短臂为富含GC对的非45S rDNA位点。该实验建立了莪术的经典核型,为非整倍体,核型公式为2n=62+1=40m+12sm+1m,其核型不对称性为2A型。  相似文献   

2.
簇毛麦和中间偃麦草rRNA基因位点双色荧光原位杂交分析   总被引:4,自引:0,他引:4  
簇毛麦和中间偃麦草是小麦改良的重要抗源,为了对导入的外源染色体及片段进行有效鉴定,应用分带和双色荧光原位杂交,将25S-5.8S-18S rRNA、5S rDNA基因分别定于簇毛麦染色体1V短臂和5V短臂上。分别在中间偃麦草的3对、4对染色体上观察到25S-5.8S-18S rRNA和5S rRNA基因,其中有2对染色体在其短臂上有两种核糖体RNA基因。  相似文献   

3.
以加拿大披碱草为材料,通过染色体原位杂交的方法,确定加拿大披碱草的45S rDNA在染色体上的位置,旨在为加拿大披碱草育种提供依据.结果表明,45S rDNA在加拿大披碱草的染色体上检测出4个位点(绿色),它们分别位于第2对染色体短臂末端和第5对染色体短臂次缢痕上,即核仁组织区(NOR),且杂交信号强弱较一致.  相似文献   

4.
为给葱的染色体的识别提供新标记,建立葱的分子细胞遗传学核型,本研究采用去壁火焰干燥法制备了分散且形态良好的葱中期染色体,并进行了CPD(PI和DAPI组合)染色和45S rDNA荧光原位杂交(FISH),根据葱染色体的形态特征,结合CPD染色和FISH结果,对葱进行了核型分析。CPD染色结果:葱所有染色体臂末端都显示CPD带。FISH结果:有一对45S rDNA位点(在第5对染色体上)。葱的核型公式:2n=2x=16=2sm+12m+2st(SAT)。研究表明:利用CPD染色和45S rDNA FISH,不仅能为染色体识别提供新标记,还能了解染色体GC丰富区的分布,为葱属植物的物种鉴定、系统分类与进化等研究提供DNA分子方面的证据。  相似文献   

5.
《种子》2020,(8)
以偏穗鹅观草(Roegneria komarovii)为试验材料,利用荧光原位杂交技术,进行5 S rDNA、45 S rDNA以及重复序列pAs 1 DNA的定位,观察荧光原位杂交信号的分布特征以及信号的强弱,对偏穗鹅观草进行染色体配对以及核型分析。结果表明:1)偏穗鹅观草的染色体组总长度为104.785 μm,平均绝对长度为7.485 μm,最长染色体与最短染色体长度比为2.030,臂比大于2∶1的染色体有0组,核型不对称系数为56.01%,具有2对随体,分别位于第6号染色体和第14号染色体的短臂上,故偏穗鹅观草的核型公式是2 n=4 x=28=26 m(4 SAT)+2 sm,核型类型属于1 B型。2) 5 S rDNA位于第6对染色体的短臂上和第11对染色体的长臂上;45 S rDNA位于第6对染色体的短臂上和第14对染色体的短臂上;有8对染色体检测到明显的pAs 1 DNA的荧光信号,大多分布于染色体的端部,少数定位于着丝粒区域。  相似文献   

6.
基于45S rDNA和雷蒙德氏棉gDNA为探针的草棉FISH核型研究   总被引:1,自引:0,他引:1  
 草棉基于荧光原位杂交(FISH)的核型公式为2n = 2x = 26 = 16m + 10sm (6 sat),短臂和长臂的相对长度分别为1.43~4.14和3.34~5.18,染色体长度比(最长与最短染色体的比值)是1.63。染色体组有6个随体,都定位在最后3条染色体的短臂上,其中位于第12和第13号染色体的随体在DAPI和罗丹明镜像中明显可见,但位于第11号染色体的随体在DAPI镜像中观察不到。检测到6个(3对)NOR信号,与随体同位,1对位于染色体端粒,2对紧接着丝粒。雷蒙德氏棉基因组DNA(gDNA)作探针时,在体细胞染色体上检测到GISH-NOR,其数量、位置和大小与45S探针的NOR相同,说明FISH核型比以前常规核型(非FISH核型)更精确。结合本试验室其它FISH资料,推断A基因组棉种在作为供体形成异源四倍体棉种以来,一些串连重复序列如rDNA可能发生了很大变化,包括扩增、易位或缺失等。对于D基因组特有的GISH-NOR的一个可能解释,就是D基因组棉种的rDNA拷贝数远远多于A基因组棉种。NOR或者GISH-NOR位点等方面的进一步研究,有助于探讨rDNA基因进化和功能,并作为一种标记应用于棉属构建染色体序号定位的物理图谱。  相似文献   

7.
花生的荧光显带和rDNA荧光原位杂交核型分析   总被引:1,自引:0,他引:1  
建立花生准确而详细的核型对于阐明其起源和开展其基因组研究十分重要。本研究采用DAPI显带和5S、45S rDNA探针双色荧光原位杂交对花生有丝分裂中期染色体进行了分析。结果表明,花生的单倍基因组总长度为(81.06±3.74) μm,最长染色体为(4.72±0.15) μm,最短染色体为(2.62±0.14)μm;有15对染色体显示了着丝粒区DAPI+带,其中10对为强带,5对为弱带;有2对5S rDNA位点和5对45S rDNA位点,其中1对5S与1对45S位点同线。综合染色体测量数据、DAPI+带和rDNA杂交信号,对花生染色体进行了准确配对和排列,建立了详细的分子细胞遗传学核型。花生的核型公式为2n=4x=40=38m+2sm(SAT),核型不对称类型属于2A型。  相似文献   

8.
总共944表达序列标记(ESTs)形成了2212个EST位点;这些位点被绘制在六倍体小麦(Triticum aestivum L.)的部分同源组1染色体上。为了表示EST分布情况,构成了EST缺失图和组1染色体的共有序列图。EST位点在染色体1A、1B和1D中表现为不规则分布,分别分布有660、826和726个EST。对全部3个染色体而言,其长臂上的EST位点数比短臂上的多一些。EST在染色体臂上的分布不是随机的,EST群出现在短臂的末端区域和长臂的中间区域。  相似文献   

9.
应用GISH与STS标记鉴定小麦-中间偃麦草抗黄矮病端体系   总被引:3,自引:3,他引:0  
由大麦黄矮病毒引起的小麦黄矮病毒病是一个严重病害,至今在小麦属内还没有发现抗源。中间偃麦草2Ai-2染色体携带一个高抗黄矮病基因,对该基因的染色体臂定位将为制定抗病基因向小麦转移策略,筛选、开发特定的、与抗性连锁的分子标记的研究提供重要信息。本文对由小麦-中间偃麦草二体附加系Z6衍生的3个抗黄矮病端体系进行鉴定,通过分析端体的遗传构成、筛选与端体共分离的STS标记以确定端体在遗传上的染色体臂归属,从而明确BYDV抗病基因的染色体位置。以拟鹅冠草基因组[Pseudoroegneria strigosa (M. Bieb.) Löve,St]DNA为探针,中国春基因组(Triticum aestivum L., ABD) DNA作封阻分别对抗病亲本Z6及抗病端体系N530的根尖体细胞染色体进行原位杂交,结果表明,N530体细胞中有2个端体显示出与Z6中外源染色体2Ai-2短臂相似, 而与长臂不同的杂交信号。以小麦第2同源群的5个RFLP探针的DNA序列为基础,设计了6对PCR引物,对小麦-中间偃麦草二体异附加系、二体代换系和端体系进行扩增,结果表明,基于短臂探针psr126,psr131序列设计的2对引物,可在含有2Ai-2染色体及端体的抗黄矮病材料中特异扩增,而基于长臂探针psr112序列设计的1对引物,可在含有2Ai-2染色体的抗黄矮病材料中特异扩增,但不能在端体系进行特异扩增,证明外源端体为2Ai-2染色体的短臂。本研究不仅将黄矮病抗性基因定位于2Ai-2染色体的短臂上, 而且由RFLP探针psr126、psr131和psr112序列转化的标记STS126 (sequence tagged site) STS131和STS112还可分别作为追踪2Ai-2染色体短臂和长臂的分子标记,用于抗病易位系辅助选择。  相似文献   

10.
由于缺乏明确的二倍体供体信息,燕麦属植物的起源和系统进化关系一直存在争议。利用荧光原位杂交(fluorescence in situ hybridization,FISH)方法,检测45S rDNA和5S rDNA在燕麦属不同倍性植物染色体上的位点信息;并依据已公开的45S rDNA ITS区全长DNA序列构建分子进化树。探讨燕麦属植物在不同基因组中45S rDNA的位点变化、进化规律以及分化机制,为探究燕麦属物种的起源与演化提供参考。  相似文献   

11.
水仙荧光原位杂交体系的建立   总被引:2,自引:0,他引:2  
摘要:建立以水仙染色体为靶、rDNA为探针的荧光原位杂交实验技术,为进一步利用荧光原位杂交技术分析水仙的亲缘和进化关系奠定了基础。水仙的染色体制片以去壁低渗-火焰干燥法较好,容易获得大量清晰、分散的有丝分裂中期相;切刻平移法地高辛标记探针、染色体和探针共变性90℃ 5 min能有效的进行水仙rDNA的染色体荧光原位杂交定位。  相似文献   

12.
Detailed karyotypes of Hydrangea macrophylla, Hydrangea paniculata and Hydrangea quercifolia were constructed on the basis of arm lengths and centromeric index, together with 45S rDNA fluorescence in situ hybridization. Although the chromosomes were small, they were well distinguishable for all species. Chromosome morphology and karyotypes were different for the three species. H. macrophylla had six metacentric (M), eight submetacentric (SM) and four subtelocentric (ST) chromosomes. The karyotype of H. paniculata contained seven M, 10 SM and one ST chromosomes and H. quercifolia had six M, 10 SM and two ST chromosomes. The variability among three species also was expressed by 45S rDNA signals. H. macrophylla had a nucleolar organizing region on chromosome 2, H. paniculata had 45S rDNA signals on chromosomes 2, 5 and 11 and H. quercifolia on chromosomes 3 and 8. Hybridization signal always was distally on the short arm but the strength of the signals was different for the three species. The chromosome portraits made in this study will be used to trace chromosome behaviour in interspecific hybrids resulting from breeding work between the three species.  相似文献   

13.
岷江百合根尖染色体的C-分带和FISH分析   总被引:5,自引:0,他引:5  
利用Giemsa C-分带和荧光原位杂交(FISH)的方法对岷江百合(L.regale)根尖染色体进行了研究.结果表明岷江百合的带型公式为:2n=24=4I 8CL 2I 6I 2I T 2I T ,每条染色体都显示出了可以明显区别的特征带,带纹强弱差异明显.以45S rDNA为探针对岷江百合根尖染色体进行了荧光原位杂交,杂交点数为5对,分别位于A、B、H和K 4对同源染色体的着丝点区域和一对G染色体的长臂上.通过Giemsa C-带和HSH的方法可以将岷江百合的每条染色体区分开来.  相似文献   

14.
In this study, Tulipa fosteriana was found to contain 45S rDNA repeat units of 9.7 and 9.5 kb, in which at least 7 types of 45S rDNAs were identified by restriction site analysis. For 5S rDNA, repeat units ranging from 364 bp to 396 bp were identified. The diploid cultivars (2n = 2x = 24) ‘Christmas Dream’ and ‘Queen of Night,’ representing the horticultural group T. gesneriana, and ‘Red Emperor’, belonging to T. fosteriana, were compared cytogenetically using cloned 5S and 45S rDNAs. Fluorescence in situ hybridization (FISH) analysis identified many rDNA sites located on each chromosome in the diploid genomes. For example, we identified 71 sites of 5S rDNA and 10 sites of 45S rDNA in ‘Red Emperor’. Additionally, FISH analyses enabled construction of karyotypes for these cultivars. Karyotype comparison of T. gesneriana cultivars showed conservation of repetitive rDNA unit positioning. A clear difference in chromosome size and signal pattern was observed between T. gesneriana and T. fosteriana cultivars. Here we demonstrate the unique nature of the highly repeated 5S rDNA units in these Tulipa species and the usefulness of FISH karyotyping with cloned 5S and 45S rDNAs to clearly distinguish between chromosomes from T. gesneriana and T. fosteriana. Hitoshi Mizuochi and Agnieszka Marasek contributed equally to this paper  相似文献   

15.
植物体细胞杂交是植物种质资源创制的重要方法。体细胞杂种在原生质体再生的过程中染色体会产生非常多的遗传变异。研究体细胞杂种的染色体行为为马铃薯体细胞杂种的创制和利用提供理论基础。本研究采用rDNA和端粒重复序列作为探针进行原位杂交(fluorescence in situ hybridization),并结合基因组原位杂交(genomic in situ hybridization),对马铃薯和茄子体细胞杂种染色体组成和变异进行了分析。原位杂交结果表明,体细胞杂种中存在马铃薯和茄子融合的染色体和双着丝粒染色体,并发现部分融合染色体是由马铃薯和茄子2号染色体末端对末端融合得到的。重排的双着丝粒染色体的着丝粒一个来源于马铃薯,一个来源于茄子。此外,体细胞杂种中来源于茄子的5S rDNA在体细胞杂种再生及稳定的过程中全部丢失。研究结果表明马铃薯与茄子在进行体细胞杂交的过程中,染色体是不稳定的,容易造成融合后代出现双着丝粒和染色体重排等现象。体细胞杂种的染色体会通过染色体重排、双着丝粒、rDNA均一化等多种形式使其染色体趋于稳定。  相似文献   

16.
The karyotypes of species in the genus Clivia were analyzed by using Giemsa C-banding, fluorochrome staining, silver impregnation and in situ hybridization. Banded ideograms were established with computer aided image analysis. A chromosome number of 2n = 22 and a similar basic karyotype, based on relative chromosome length and arm ratio, was found in all the four species. There were clear differences in banding pattern between the species which allowed their karyotypes, and consequently the species, to be unambiguously identified. Apart from at the centromere, heterochromatin was mainly distributed on the short arms of the smaller chromosomes. Amounts of heterochromatin in C. miniata and C. gardenii were greater than in the other two species. The number of pairs of rDNA sites, identified by in situ hybridization, ranged from one to three. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

17.
Resynthesized Brassica napus L. is an important source for broadening genetic diversity and producing lines with desired characteristics. It is also a fine model to study the processes of genomic reorganizations in recently formed polyploids. We firstly performed molecular cytogenetic characterization of newly resynthesized rapeseed (B. rapa ssp. narinosa × B. oleracea ssp. capitata) and its parental species, and also examined genomic changes in hybrids of the succeeding generations grown under pressure of selection of yellow-seeded progeny. For karyotype studies, FISH/GISH with 45S, 5S rDNA, C genome specific BoB014O06 BAC clone and genomic DNA of parental B. rapa was performed. Synthetic S0–S2 hybrids had common rapeseed karyotypes (2n = 38) including 14 loci of 45S rDNA sites and 10 loci of 5S rDNA. Progeny selection led to gradual deletion of C genome chromosomes in hybrid karyotypes. So, in karyotypes of S6 and S7 hybrids, the chromosome number was reduced to 2n = 20–22, and only chromosomes of A genome bearing 10–13 loci of 45S rDNA and 8–10 loci of 5S rDNA, variations in chromosome number, chromosome rearrangements as well as examples of trisomy and monosomy were revealed. Our findings indicate an enhanced genome instability in resynthesized rapeseed lines developed under the pressure of selection which might lead to chromosome rearrangements or/and deletions and even elimination of the whole parental genome in hybrids in succeeding generations. The approach can be useful for the development of rapeseed lines with trisomy, chromosome addition/substitution lines important for genetics and plant breeding.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号