甘蓝染色体图谱的构建及SI基因的定位研究
摘要
荧光原位杂交是一种有力的细胞遗传学研究工具,现广泛应用于基因的定位、染色体结构的研究、细胞遗传图谱和染色体图谱的构建。甘蓝作为芸(?)属三个基本种之一,也是芸(?)属基因组计划研究对象之一,因此,利用荧光原位杂交技术,构建甘蓝的染色体图谱以及细胞遗传图谱,直观地展现基因、分子标记等在染色体上的具体位置,成为甘蓝分子细胞遗传学研究的主要内容。同时,自交不亲和作为甘蓝防止自交的一种重要生殖隔离方式,其信号传导途径除受一个带有复等位基因的多态性S位点(S-locus)控制外,还与另一些信号传导元件(MLPK.ARCl.SSP等)密切相关。但是,关于这条信号传导途径相关元件编码基因与S位点之间的连锁关系、以及它们在甘蓝染色体上的具体位置分布情况还有待研究。本研究以自交不亲和甘蓝为材料,采用荧光原位杂交技术,将重复序列5S rDNA.标记位点(pO147、pR94和pN120)以及自交不亲和基因MLPK和SRK分别进行染色体定位研究,旨在构建甘蓝染色体图谱以及细胞遗传图谱,明确自交不亲和基因在染色体的具体位置及连锁关系,这对芸(?)属基因组计划和自交不亲和的机理研究具有非常重要的意义。
主要研究结果如下.
1.靶DNA载体的制备：利用甘蓝的根尖、花蕾、以及幼叶,成功地制备出不同伸长度的靶DNA载体,包括甘蓝根尖和绒毡层细胞的中期染色体、粗线期染色体和伸展DNA纤维。
A.甘蓝根尖中期染色体制备：在暗培养条件下采用变温同步化处理根尖,明显提高了根尖细胞中期分裂相；根尖预处理采用的是0.002 mol／L 8-羟基喹啉预处理1 h,获得了最佳的效果；2%纤维素酶和2%果胶酶混合液在37℃水浴锅中酶解约40～90min,并进行前后低渗,可以获得分散良好、背景较低的根尖中期染色体分裂相；
B.绒毡层细胞中期染色体以及粗线期染色体的制备：以田间采取的花蕾为材料,70%乙醇中-20℃保存备用,保存时间在3个月内；选取具有理想分裂相的花药,在2%(w／v)纤维素酶和2%(w／v)果胶酶的混合酶液中酶解60 min,可以获得染色体分散、背景较低的染色体制片；
C.伸展DNA纤维的制备：采用匀浆法获得分布均匀、杂质较少、密度适中的细胞核；采用分子梳理法制备出伸展度良好、密度合适以及平行的DNA纤维。
2. FISH体系的建立：通过荧光原位杂交相关参数的探索,建立了适合不同伸长度的靶DNA载体FISH体系。对中期和粗线期染色体制片采用相同的处理步骤,而DNA纤维制片无需进行蛋白酶处理和预变性。
A.片子的预处理：100μ/mL的RNase A 37℃处理1 h可以增强杂交的信噪比；500ug/mL胃蛋白酶在37℃处理40 mmin可以有效的去除蛋白质；70%去离子甲酰胺中70℃变性2 min可获得较好的杂交效果。
B.杂交混合液组成：去离子甲酰胺50%；硫酸葡聚糖7.5%；2×SSC；1.5 ng/μL探针；0.5%SDS；0.5μg/Lц鱼精DNA。
C.洗脱条件：重复拷贝基因,洗脱温度42℃,洗脱时间8 min；低拷贝或单拷贝基因,洗脱温度37℃,洗脱时间5 min；如果靶DNA为DNA纤维时,洗脱温度40℃,洗脱时间5 min。
3.甘蓝根尖中期染色体的核型分析：甘蓝体细胞染色体数2n=18,其核型公式为K(2n)=18=12m+6sm,其中1、2、4、5、6和8号染色体为中部着丝粒染色体,3、7和9号染色体为近中部着丝粒染色体；7号染色体的短臂末端具有随体；甘蓝的核型属于2A型,即对称型核型。
4.高分辨率5S rDNA-FISH研究：以羽衣甘蓝为实验材料,采用荧光原位杂交技术将DIG标记的5S rDNA探针定位于不同分辨率的绒毡层细胞中期染色体、粗线期染色体以及伸长DNA纤维上,目的是明确羽衣甘蓝5S rDNA在染色体的分布和具体拷贝数情况,为进一步利用FISH进行基因定位和细胞遗传图谱构建奠定基础。在中期染色体和粗线期染色体上,都同时获得3个杂交信号位点(a、b、c),且位于2号染色体的长臂近着丝粒区域,其信号强度为b>a>c；而在伸长DNA纤维上,出现了3种不同长度的念珠状长链(a、b、c),其物理大小分别为257 kb、359 kb和134 kb,粗略估算出3个5S rDNA位点的拷贝数分别为510、712和266。
5.甘蓝2号染色体细胞遗传图普的构建：以甘蓝第4连锁群上的3个标记位点(p0147、pR94和pN120)和5S rDNA为探针,并分别用生物素和地高辛标记,然后与甘蓝绒毡层细胞中期染色体和粗线期染色体进行双色荧光原位杂交,构建甘蓝2号染色体细胞遗传图谱,明确分子标记在染色体上的真实距离。
A.标记探针的获得：采用探针加长法即将p0147的序列长度增加为8 kb左右,pR94的长度增加到2.5 kb,pN120的长度增加为3.2 kb,提高了杂交的检出率。
B.采用3种长度的探针对杂交检出率的探索：探针长度为2 kb时,其检出率为9.8%；探针长度为4.5 kb时,检出率约有提高,达到16.7%,而当探针长度达到8 kb时,探针的检出率增长为20.2%。
C.2号染色体细胞遗传图谱：探针pO147、pR94和pN120均定位于甘蓝2号染色体的短臂(2S),细胞遗传位置分别为为2S.13、2S.9和2S.15。
6.自交不亲和基因MLPK和SRK的定位：以MLPK和SRK基因序列为探针,分别在甘蓝绒毡层细胞中期染色体、减数分裂粗线期染色体上进行双色荧光原位杂交,确定MLPK和SRK在染色体上的分布情况和拷贝数。MLPK位于第2条染色体的短臂中部,细胞遗传位置为2S.17；SRK位于甘蓝的4号染色体的长臂中部,细胞遗传位置为4L.80。在中期染色体上,MLPK探针的检出率为10.2%,SRK探针的检出率为12.2%；在粗线期染色体上,MLPK的信号检出率为26.9%,SRK探针的检出率为33.7%。
7.甘蓝染色体图谱：第4连锁群的遗传标记位点(pR94、pO147、pN120)、自交不亲和基因MLPK以及高度重复的5S rDNA序列都同时位于甘蓝的2号染色体上,SRK基因位于7连锁群即第4号染色体的长臂。
Fluorescence in situ hybridization (FISH) is a powerful cytogenetic technique that can be used to detect and localize the genes on chromosomes, which is widely used to study the localization of genes and the structure of chromosome, construct the cytogenetic and chromosomal maps. Brassica oleracea is one of the three diploid Brassica species and researched by multinational Brassica Genome Project (MBGP). Therefore, the main content of molecular cytogenetic study is to construct the chromosomal or cytogenetic maps of B.oleracea and directly show the positions of genes and genetically maped markers on chromosomes by FISH. Simultaneously, self-incompatibility is one of the most important means to prevent selfing and thus encourage outcrossing. Besides, the mechanism of signal transduction is controlled by a single locus termed S, which has many different alleles, it is closely related to the other signal transduction elements (MLPK,ARC1, SSP, et al). However, the linkage relationships between these elements and SI genes and their positions on chromosomes are poorly described and further reseached. In this research, self-incompatibility B.oleracea var. acephala was used as the experimental material, The probes of the repeated sequence 5S rDNA, markers (pO147, pR94 and pN120) and SI genes (MLPK and SRK) were located on chromosomes of B.oleracea by FISH,, our aim is to construct chromosomal and cytogenetic maps and determine the localization on chromosome and the linkage relationship of SI genes, it is very important to MBGP and the mechanism of SI.
The study results were as follows:
1. Target DNA preparations:it was successfully prepared different extension degree in B.oleracea root tips, buds and Young leaves, including metaphase chromosomes from the mitotic divisions of root tips and tapetal cells, pachytene chromosomes from the pollen mother cells and the extended DNA fibers (EDF).
A. Preparations of metaphase chromosomes of root tips:the Synchronous processing of B. oleracea root tips with varying temperature greatly improved cell divisions at metaphase; It could obtain the best pretreatment effect with 0.002 mol/L 8-hydroxy quinoline for 1 h; the root tips were treated with digestion for 40-90 min in the mixture of 2%(W/V) Cellulase and 2%(W/V) Pectinase at 37℃, it was obtained the Good dispersion and low background cell division of root tips.
B. Preparations of metaphase chromosomes of tapetal cell and pachytene chromosomes: flower buds were taken from plants and stored in 70%ethanol at 4℃for up to 3 months; the anthers were digested in enzyme mixture 2%cellulase and 2%pectinase at 37℃for 60 min.
C. Preparations of extended DNA fibers:nuclei with uniform distribution, equal density and little impurities were obtained by the method of homogenization; the good extension, moderate density and parallel DNA fibers were successfully prepared by molecular combing.
2. FISH system:it was found to be applied to targets DNA of different extension degree and different types of probes by the research of correlative parameters during FISH, the procedures of FISH were basically identical in metaphase and pachytene chromosomes. However, the slides of EDFs were not pretreated and pre-denatured.
A. Pretreatment of targets DNA on slides:in order to improve the signal-to-noise ratio in hybridization, it must be done by incubation the preparation in RNase A (100μg/mL) at 37℃for 60 min; the protein that surrounds the target nucleic acid was digested for 40 min at 37℃in 2×SSC by pepsin (500 ug/ml); the good hybridization results were obtained by the denaturation for 2min in 70%deionized formamide at 70℃.
B. The hybridization mixture:50%deionized formamide; 7.5%dextran sulfate; 2x SSC,1.5 ng/μL probes,0.5%SDS, and 0.5/μg/μL herring sperm DNA.
C. Posthybridization washes:for repetitive probes, the slides were washed at 42℃for 8 min; for unique probes, it is washed at 37℃for 5 min; if target DNA is DNA fibers, it is washed at 40℃for 5 min..
3. The karyotype analysis of metaphase chromosomes:the chromosome numbers were 18, the karyotype formula was K(2n)=18=12m+6Sm, chromosome 1,2,4,5,6, and 8 are metacentric chromosome, chromosome 3,7,9 were sub-metacentric chromosome, chromosome 7 has a statellite in the short arm; The chromosome type of B.oleracea belonged to 2A type, that is a symmetrical karyotype.
4. High-resolution 5S rDNA-FISH:B.oleracea var. acephala was used as the experimental material,5S rDNA probe was labeled by PCR-DIG (PCR-Digoxigenin), By FISH,5S rDNA probe was located on the metaphase chromosomes of tapetal cell, pachytene chromosomes and extended DNA fibers (EDF). The aim is to localize 5S rDNA on the chromosomes of Brassica oleracea var. acephala by FISH and estimate the copy number of 5S rDNA, further provide a basis for the location of genes and the construction of cytogenetic map of chromosome 2 by FISH. In the metaphase chromosomes of tapetal cell and pachytene chromosomes, It was observed that three closely adjacent 5S rDNA hybridization signal sites (a, b, c) located near to the centromere in the long arm of the submetacentric chromosome 2, the intensity of signals is b>a>c. In the extended DNA fibers, it was estimated that the physical size of three different stretches of beads-on-string (a, b, c) is of the order of-257 kb,359 kb and 134 kb respectively. It was proved that B.oleracea var. acephala contains three tandem repeat sites, and estimated that the copies number of three 5S rDNA locus are about 510,712 and 266 respectively.
5. Construction of a cytogenetic map of B.oleracea chromosome 2. Three markers (pO147, pR94 and pN120) mapped to linkage group 04 and 5S rDNA as FISH probes, which hybridized to the metaphase chromosomes from tapetal cells and pachytene chromosomes from PMC by double FISH. The aim is to construct the cytogenetic map of B. oleracea chromosome 2 and show the positions of genetically mapped markers on chromosome.
A. Labeled probes:the length of probes (pO147, pR94 and pN120) is about 8 kb,.5kb,3.2kb, respectively
B. The relationship between the rate of detected hybridization signals and the probe length: when a 2 kb fragment was used as a probe, the rate of detection is 9.8%; However, the probes are 4.5kb and 8 kb in length, the rate of detection is 16.7%and 20.2% respectively.
C. The cytogenetic map of B.oleracea chromosome 2:The probe pO147 was detected on 2S and mapped at cytogenetic position 2S.13; the probes (pR94 and pN120) mapped at cytogenetic position 2S.9 and 2S.15, respectively.
6. Localization of MLPK and SSP genes for self-incompatibility:the MLPK probe was hybridized on the short arm of chromosome 2 and mapped at cytogenetic position 2S.17; SRK signal was detected at a single locus on the long arm of chromosome 4 and mapped at cytogenetic position 4L.80. The rate of the hybridization signals of MLPK and SRK probe is 10.2%and 12.2 in metaphase chromosomes, respectively, in the pachytene chromosomes, however, the rate is 26.9%and 33.7%, respectively.
7. Construction of chromosomal map:the markers (pR94、pO147、pN120) on linkage group 04, self-incompatibility genes MLPK and 5S rDNA were detected on chromosome 2, SRK is located in the long arm of chromosome 2.
主要研究结果如下.
1.靶DNA载体的制备：利用甘蓝的根尖、花蕾、以及幼叶,成功地制备出不同伸长度的靶DNA载体,包括甘蓝根尖和绒毡层细胞的中期染色体、粗线期染色体和伸展DNA纤维。
A.甘蓝根尖中期染色体制备：在暗培养条件下采用变温同步化处理根尖,明显提高了根尖细胞中期分裂相；根尖预处理采用的是0.002 mol／L 8-羟基喹啉预处理1 h,获得了最佳的效果；2%纤维素酶和2%果胶酶混合液在37℃水浴锅中酶解约40～90min,并进行前后低渗,可以获得分散良好、背景较低的根尖中期染色体分裂相；
B.绒毡层细胞中期染色体以及粗线期染色体的制备：以田间采取的花蕾为材料,70%乙醇中-20℃保存备用,保存时间在3个月内；选取具有理想分裂相的花药,在2%(w／v)纤维素酶和2%(w／v)果胶酶的混合酶液中酶解60 min,可以获得染色体分散、背景较低的染色体制片；
C.伸展DNA纤维的制备：采用匀浆法获得分布均匀、杂质较少、密度适中的细胞核；采用分子梳理法制备出伸展度良好、密度合适以及平行的DNA纤维。
2. FISH体系的建立：通过荧光原位杂交相关参数的探索,建立了适合不同伸长度的靶DNA载体FISH体系。对中期和粗线期染色体制片采用相同的处理步骤,而DNA纤维制片无需进行蛋白酶处理和预变性。
A.片子的预处理：100μ/mL的RNase A 37℃处理1 h可以增强杂交的信噪比；500ug/mL胃蛋白酶在37℃处理40 mmin可以有效的去除蛋白质；70%去离子甲酰胺中70℃变性2 min可获得较好的杂交效果。
B.杂交混合液组成：去离子甲酰胺50%；硫酸葡聚糖7.5%；2×SSC；1.5 ng/μL探针；0.5%SDS；0.5μg/Lц鱼精DNA。
C.洗脱条件：重复拷贝基因,洗脱温度42℃,洗脱时间8 min；低拷贝或单拷贝基因,洗脱温度37℃,洗脱时间5 min；如果靶DNA为DNA纤维时,洗脱温度40℃,洗脱时间5 min。
3.甘蓝根尖中期染色体的核型分析：甘蓝体细胞染色体数2n=18,其核型公式为K(2n)=18=12m+6sm,其中1、2、4、5、6和8号染色体为中部着丝粒染色体,3、7和9号染色体为近中部着丝粒染色体；7号染色体的短臂末端具有随体；甘蓝的核型属于2A型,即对称型核型。
4.高分辨率5S rDNA-FISH研究：以羽衣甘蓝为实验材料,采用荧光原位杂交技术将DIG标记的5S rDNA探针定位于不同分辨率的绒毡层细胞中期染色体、粗线期染色体以及伸长DNA纤维上,目的是明确羽衣甘蓝5S rDNA在染色体的分布和具体拷贝数情况,为进一步利用FISH进行基因定位和细胞遗传图谱构建奠定基础。在中期染色体和粗线期染色体上,都同时获得3个杂交信号位点(a、b、c),且位于2号染色体的长臂近着丝粒区域,其信号强度为b>a>c；而在伸长DNA纤维上,出现了3种不同长度的念珠状长链(a、b、c),其物理大小分别为257 kb、359 kb和134 kb,粗略估算出3个5S rDNA位点的拷贝数分别为510、712和266。
5.甘蓝2号染色体细胞遗传图普的构建：以甘蓝第4连锁群上的3个标记位点(p0147、pR94和pN120)和5S rDNA为探针,并分别用生物素和地高辛标记,然后与甘蓝绒毡层细胞中期染色体和粗线期染色体进行双色荧光原位杂交,构建甘蓝2号染色体细胞遗传图谱,明确分子标记在染色体上的真实距离。
A.标记探针的获得：采用探针加长法即将p0147的序列长度增加为8 kb左右,pR94的长度增加到2.5 kb,pN120的长度增加为3.2 kb,提高了杂交的检出率。
B.采用3种长度的探针对杂交检出率的探索：探针长度为2 kb时,其检出率为9.8%；探针长度为4.5 kb时,检出率约有提高,达到16.7%,而当探针长度达到8 kb时,探针的检出率增长为20.2%。
C.2号染色体细胞遗传图谱：探针pO147、pR94和pN120均定位于甘蓝2号染色体的短臂(2S),细胞遗传位置分别为为2S.13、2S.9和2S.15。
6.自交不亲和基因MLPK和SRK的定位：以MLPK和SRK基因序列为探针,分别在甘蓝绒毡层细胞中期染色体、减数分裂粗线期染色体上进行双色荧光原位杂交,确定MLPK和SRK在染色体上的分布情况和拷贝数。MLPK位于第2条染色体的短臂中部,细胞遗传位置为2S.17；SRK位于甘蓝的4号染色体的长臂中部,细胞遗传位置为4L.80。在中期染色体上,MLPK探针的检出率为10.2%,SRK探针的检出率为12.2%；在粗线期染色体上,MLPK的信号检出率为26.9%,SRK探针的检出率为33.7%。
7.甘蓝染色体图谱：第4连锁群的遗传标记位点(pR94、pO147、pN120)、自交不亲和基因MLPK以及高度重复的5S rDNA序列都同时位于甘蓝的2号染色体上,SRK基因位于7连锁群即第4号染色体的长臂。
Fluorescence in situ hybridization (FISH) is a powerful cytogenetic technique that can be used to detect and localize the genes on chromosomes, which is widely used to study the localization of genes and the structure of chromosome, construct the cytogenetic and chromosomal maps. Brassica oleracea is one of the three diploid Brassica species and researched by multinational Brassica Genome Project (MBGP). Therefore, the main content of molecular cytogenetic study is to construct the chromosomal or cytogenetic maps of B.oleracea and directly show the positions of genes and genetically maped markers on chromosomes by FISH. Simultaneously, self-incompatibility is one of the most important means to prevent selfing and thus encourage outcrossing. Besides, the mechanism of signal transduction is controlled by a single locus termed S, which has many different alleles, it is closely related to the other signal transduction elements (MLPK,ARC1, SSP, et al). However, the linkage relationships between these elements and SI genes and their positions on chromosomes are poorly described and further reseached. In this research, self-incompatibility B.oleracea var. acephala was used as the experimental material, The probes of the repeated sequence 5S rDNA, markers (pO147, pR94 and pN120) and SI genes (MLPK and SRK) were located on chromosomes of B.oleracea by FISH,, our aim is to construct chromosomal and cytogenetic maps and determine the localization on chromosome and the linkage relationship of SI genes, it is very important to MBGP and the mechanism of SI.
The study results were as follows:
1. Target DNA preparations:it was successfully prepared different extension degree in B.oleracea root tips, buds and Young leaves, including metaphase chromosomes from the mitotic divisions of root tips and tapetal cells, pachytene chromosomes from the pollen mother cells and the extended DNA fibers (EDF).
A. Preparations of metaphase chromosomes of root tips:the Synchronous processing of B. oleracea root tips with varying temperature greatly improved cell divisions at metaphase; It could obtain the best pretreatment effect with 0.002 mol/L 8-hydroxy quinoline for 1 h; the root tips were treated with digestion for 40-90 min in the mixture of 2%(W/V) Cellulase and 2%(W/V) Pectinase at 37℃, it was obtained the Good dispersion and low background cell division of root tips.
B. Preparations of metaphase chromosomes of tapetal cell and pachytene chromosomes: flower buds were taken from plants and stored in 70%ethanol at 4℃for up to 3 months; the anthers were digested in enzyme mixture 2%cellulase and 2%pectinase at 37℃for 60 min.
C. Preparations of extended DNA fibers:nuclei with uniform distribution, equal density and little impurities were obtained by the method of homogenization; the good extension, moderate density and parallel DNA fibers were successfully prepared by molecular combing.
2. FISH system:it was found to be applied to targets DNA of different extension degree and different types of probes by the research of correlative parameters during FISH, the procedures of FISH were basically identical in metaphase and pachytene chromosomes. However, the slides of EDFs were not pretreated and pre-denatured.
A. Pretreatment of targets DNA on slides:in order to improve the signal-to-noise ratio in hybridization, it must be done by incubation the preparation in RNase A (100μg/mL) at 37℃for 60 min; the protein that surrounds the target nucleic acid was digested for 40 min at 37℃in 2×SSC by pepsin (500 ug/ml); the good hybridization results were obtained by the denaturation for 2min in 70%deionized formamide at 70℃.
B. The hybridization mixture:50%deionized formamide; 7.5%dextran sulfate; 2x SSC,1.5 ng/μL probes,0.5%SDS, and 0.5/μg/μL herring sperm DNA.
C. Posthybridization washes:for repetitive probes, the slides were washed at 42℃for 8 min; for unique probes, it is washed at 37℃for 5 min; if target DNA is DNA fibers, it is washed at 40℃for 5 min..
3. The karyotype analysis of metaphase chromosomes:the chromosome numbers were 18, the karyotype formula was K(2n)=18=12m+6Sm, chromosome 1,2,4,5,6, and 8 are metacentric chromosome, chromosome 3,7,9 were sub-metacentric chromosome, chromosome 7 has a statellite in the short arm; The chromosome type of B.oleracea belonged to 2A type, that is a symmetrical karyotype.
4. High-resolution 5S rDNA-FISH:B.oleracea var. acephala was used as the experimental material,5S rDNA probe was labeled by PCR-DIG (PCR-Digoxigenin), By FISH,5S rDNA probe was located on the metaphase chromosomes of tapetal cell, pachytene chromosomes and extended DNA fibers (EDF). The aim is to localize 5S rDNA on the chromosomes of Brassica oleracea var. acephala by FISH and estimate the copy number of 5S rDNA, further provide a basis for the location of genes and the construction of cytogenetic map of chromosome 2 by FISH. In the metaphase chromosomes of tapetal cell and pachytene chromosomes, It was observed that three closely adjacent 5S rDNA hybridization signal sites (a, b, c) located near to the centromere in the long arm of the submetacentric chromosome 2, the intensity of signals is b>a>c. In the extended DNA fibers, it was estimated that the physical size of three different stretches of beads-on-string (a, b, c) is of the order of-257 kb,359 kb and 134 kb respectively. It was proved that B.oleracea var. acephala contains three tandem repeat sites, and estimated that the copies number of three 5S rDNA locus are about 510,712 and 266 respectively.
5. Construction of a cytogenetic map of B.oleracea chromosome 2. Three markers (pO147, pR94 and pN120) mapped to linkage group 04 and 5S rDNA as FISH probes, which hybridized to the metaphase chromosomes from tapetal cells and pachytene chromosomes from PMC by double FISH. The aim is to construct the cytogenetic map of B. oleracea chromosome 2 and show the positions of genetically mapped markers on chromosome.
A. Labeled probes:the length of probes (pO147, pR94 and pN120) is about 8 kb,.5kb,3.2kb, respectively
B. The relationship between the rate of detected hybridization signals and the probe length: when a 2 kb fragment was used as a probe, the rate of detection is 9.8%; However, the probes are 4.5kb and 8 kb in length, the rate of detection is 16.7%and 20.2% respectively.
C. The cytogenetic map of B.oleracea chromosome 2:The probe pO147 was detected on 2S and mapped at cytogenetic position 2S.13; the probes (pR94 and pN120) mapped at cytogenetic position 2S.9 and 2S.15, respectively.
6. Localization of MLPK and SSP genes for self-incompatibility:the MLPK probe was hybridized on the short arm of chromosome 2 and mapped at cytogenetic position 2S.17; SRK signal was detected at a single locus on the long arm of chromosome 4 and mapped at cytogenetic position 4L.80. The rate of the hybridization signals of MLPK and SRK probe is 10.2%and 12.2 in metaphase chromosomes, respectively, in the pachytene chromosomes, however, the rate is 26.9%and 33.7%, respectively.
7. Construction of chromosomal map:the markers (pR94、pO147、pN120) on linkage group 04, self-incompatibility genes MLPK and 5S rDNA were detected on chromosome 2, SRK is located in the long arm of chromosome 2.
引文
[1]陈瑞阳,李懋学.关十植物核型分析的标准化问题.武汉植物学研究,1985,3(4)：297-302.
[2]Stebbins G L.Chromosome evolution in higher plants. London:Edward Arnold,1971.
[3]周雪雁,关伟军,马月辉,刘佳林.染色体显带技术及其在生物学研究中的意义.上海畜牧兽牧通讯,2004,5：2-3.
[4]Endo T R. Complete identification of common wheat chromosomes by means of the c-banding technique. Genetics,1986,61-93.
[5]王晓惠,罗鹏.芥蓝和结球甘蓝染色体组型及C-带带型的研究.植物学报,1987,29(2)：149-155.
[6]Armstrong S J, Fransz P, Marshall D F and Jones G H. Physical mapping of DNA repetitive sequences to mitotic and meiotic chromosomes of Brassica oleracea var.alboglabra by fluorescence in situ hybridization. Heredity, 1998,81:666-673.
[7]Howell E C, Barker G C, Jones G H, Kearsey M J, King G J, Kop E P, Ryder C D, Teakle G R, Vicente J G and Armstrong S J. Integration of the cytogenetic and genetic linkage maps of Brassica oleracea. Genetics,2002,161: 1225-1234.
[8]工太霞,吴春红,黄进勇,魏文辉.甘蓝rDNA及Cotl DNA荧光原位杂交及其核型分析.武汉大学学报(理学版),2006,52(2)：230-230.
[9]陈晓丹,朱利泉,王永,荣小营等.芸(?)属A基因组DNA封阻下的甘蓝C染色体组核型分析.农业生物技术学报,2009,17(3)：504-509.
[10]Charlesworth D, Vekemans X, Castric V and Glemin S. Plant self-incompatibility systems:a molecular evolutionary perspective. New Phytologist,2005,168:61-69.
[11]Franklin F C H, Lawrence M J and Franklin-Tong V E. Cell and molecular biology of self-incompatibility in flowering plants. Int. Rev. Cytol,1995,158:1-64.
[12]McClure B A, Haring V, Ebert P R, Anderson M A, Simpson R J, Sakiyama F and Clarke A E. Style selfincompatibility gene products of Nicotiana alata are ribonucleases. Nature,1989,342:955-957.
[13]Franklin-Tong V E and Franklin F C H. The different mechanisms of gametophytic self-incompatibility. Philos. Trans. R. Soc. Lond. B. Biol. Sci.2003,358(1434):1025-1032.
[14]Sijacic P, Wang X, Skirpan A L, Wang Y, Dowd P E, McCubbin A G, Huang S, and Kao T. Identification of the pollen determinant of S-RNase-mediated self-incompatibility. Nature,2004,429:302-305.
[15]Foote H C, Ride J P, Franklin-Tong V E, Walker E A, Lawrence M J, Franklin F C. Cloning and expression of a distinctive class of self-incompatibility (S) gene from Papaver rhoeas L. Proc Natl Acad Sci. USA,1994,91: 2265-69
[16]Franklin-Tong V E, Ride J P, Read N D, Trewawas A J and Franklin F C H. The self-incompatibility response in Papaver rhoeas is mediated by cytosolic free calcium. Plant J,1993,4:163-177.
[17]Franklin-Tong V E, Hackett G and Hepler P K. Ratioimaging of Ca21 in the self-incompatibility response in pollen tubes of Papaver rhoeas. Plant J,1997,12:1375-1386.
[18]Franklin-Tong V E, Holdaway-Clarke T L, Straatman K R, Kunkel J G and Hepler P K. Involvement of extracellular calcium influx in the self-incompatibility response of Papaver rhoeas. Plant J,2002,29:333-345.
[19]Rudd J J, Franklin F C H, Lord J M and Franklin-Tong V E. Increased phosphorylation of a 26-kD pollen protein is induced by the self-incompatibility response in Papaver rhoeas. Plant Cell,1996,8:713-724.
[20]Snowman B N, Kovar D R, Shevchenko G, Franklin-Tong V E and Staiger C J. Signal-mediated depolymerization of actin in pollen during the self-incompatibility response. Plant Cell,2002,14:2613-2626.
[21]Thomas S G and Franklin-Tong V E. Self-incompatibility triggers programmed cell death in Papaver pollen. Nature,2004,429:305-309.
[22]Goodwillie C. The genetic control of self-incompatibility in Linanthus parviflorus (Polemoniaceae). Heredity, 1997,79:424-432.
[23]Hiscock S J, and Tabah D A.The different mechanisms of sporophytic self-incompatibility. Philos. Trans. R. Soc. Lond. B. Biol. Sci,2003,358(1434):1037-1045.
[24]Schopfer C R, Nasrallah M E and Nasrallah J B. The male determinant of self-incompatibility in Brassica..Science,1999,266:1697-1700.
[25]Takayama S, Shiba H, Iwano M, Shimosato H,. Che F-S, Kai N, Watanabe M, Suzuki G, Hinata K andlsogai A. The pollen determinant of self-incompatibility in Brassica campestris. Proc. Natl Acad. Sci USA,2000,97: 1920-1925.
[26]Stein J C, Howlett B, Boyes D C, NasrallahM E and Nasrallah J B. Molecular cloning of a putative receptor kinase gene encoded by the self-incompatibility locus of Brassica oleracea. Proc. Natl Acad. Sci. USA,1991,88: 8816-8820.
[27]Nasrallah J B and Nasrallah M E. Pollen-stigma signalling in the sporophytic self-incompatibility response. Plant Cell,1993,5:1325-1335.
[28]Takayama S, Shimosato H, Shiba H, Funato M, Che F E, Watanabe M, Iwano M and Isogai A. Direct ligand-receptor complex interaction controls Brassica self-incompatibility. Nature,2001,413:534-538.
[29]Murase K, Shiba H, Iwano M, Che F S, Watanabe M, Isogai A and Takayama S. A membrane-anchored protein kinase involved in Brassica self-incompatibility signaling. Science,2004,303(5663):1516-9.
[30]Harper L C, Cande W Z. Mapping a new frontier:development of integrated cytegenetic maps in plants. Funct integr Genomic,2000,1:89-98.
[31]Wang C J and Chen C C. Cytogenetic mapping in maize Cytogenet. Genome Res,2005,109:63-69.
[32]McClintock B. The relation of homozygous deficiencies to mutations and allelic series in maize. Genetics,1944, 29:478-502.
[33]Weber D and Helentjaris T. Mapping RFLP loci in maize using B-A translocations. Genetics,1989,121: 583-590.
[34]Kunzel G, Korzun L and Meister A. Cytologically integrated physical restriction fragment length polymorphism maps for the barley genome based on translocation breakpoints. Genetics,2000,154:397-412.
[35]Zhong X B, Bodeau J, Fransz P F, Williamson V M, van Kammen A, de Jong J H and Zabel P. FISH to meiotic pachytene chromosomes of tomato locates the root-knot nematode resistance gene Mi-1 and the acid phosphatase gene Aps-1 near the junction of euchromatin and pericentromeric heterochromatin of chromosome arms 6S and 6L, respectively. Theor. Appl. Genet,1999,98:365-370.
[36]Fransz P F, Armstrong S, de Jong J H, Parnell L D, van Drunen C, Dean C, Zabel P, Bisseling T and Jones G H. Integrated cytogenetic map of chromosome arm 4S of A. thaliana:Structural organization of heterochromatic knob and centromere region. Cell,2000,100:367-376.
[37]Cheng Z, Buell C R, Wing R A, Gu M and Jiang J. Toward a cytological characterization of the rice genome. Genome Res,2001,11:2133-2141.
[38]Kulikova O, Gualtieri G, Geurts R, Kim D J, Cook D, Huguet T, de Jong J H, Fransz P F and Bisseling T. Integration of the FISH pachytene and genetic maps of Medicago truncatula. Plant J,2001,27:49-58.
[39]Howell E C, Barker G C, Jones G H, Kearsey M J, King G J, Kop E P, Ryder C D, Teakle G R, Vicente J G and Armstrong S J. Integration of the cytogenetic and genetic linkage maps of Brassica oleracea. Genetics,2002,161: 1225-1234.
[40]Islam-Faridi M N, Childs K L, Klein P E, Hodnett G, Menz M A, Klein R R, Rooney W L, Mullet J E, Stelly D M and Price H J. A molecular cytogenetic map of sorghum chromosome 1. Fluorescence in situ hybridization analysis with mapped bacterial artificial chromosomes. Genetics,2002,161:345-353.
[41]Koumbaris G L and Bass H W. A new single-locus cytogenetic mapping system for maize (Zea mays L.): Overcoming FISH detection limits with marker-selected sorghum (S. propinquum L.) BAC clones. Plant J,2003, 35:647-659.
[42]Wang C R, Harper L, Cande W Z. High-Resolution Single-Copy Gene Fluorescence in Situ Hybridization and Its Use in the Construction of a Cytogenetic Map of Maize Chromosome 9. The Plant Cell,2006,18:529-544.
[43]Li L-J, Song Y-C, Yan H-M, Liu L-H. Chromosome location of two RFLP markers umc22 and umcl22 tightly linked to the Htl gene in maize. Acta Bot Sin,1998,40:1093-1097.
[44]Wang L, Song Y-C, Ning S-B, Li L-J, Liu L-H, Gu M-Q Guo L-Q. Identification of Zea diploperennis chromatins introgressed to maize via genomic in situ hybridization. Acta Bot Sin,1999,41:1264-1268.
[45]Nath J, Johnson K L. Fluorescence in situ hybridization (FISH):DNA probe production and hybridization criteria. Biotech Histochem,1998,73:6-22.
[46]Gall J and Pardue M. Formation and detection of RNA · DNA hybrid molecules in cytological preparations. Proc. Natl. Acad. Sci USA,1969,63:378-383.
[47]Langer P R, Waldrop A A and Ward D C. Enzymatic synthesis of biotin-labeled polynucleotides:Novel nucleic acid affinity probes. Proc.Natl. Acad. Sci USA,1981,78:6633-6637.
[48]Rayburn A L, Gill B S.Use of biotin-labeled probes to map specific DNA sequences on wheat chromosomes. J Hered,1985,76:78-81.
[49]De Jong J H, Fransz P F, Zabel P. High resolution FISH in plants techniques and applications. Trends Plant Sci, 1999,4:258-263.
[50]Jiang J and Gill B S.New 18S.26S ribosomal RNA gene loci:chromosomal landmarks for the evolution of polyploid wheats. Chromosoma,1994,103:179-185.
[51]Fransz P F, Alonso2Blanco C, Liharska T B, PeetersA J M, Zabel P et al. High-resolution physical mapping in A rabidopsis thaliana and tomato by fluorescence in situ hybridization to extended DNA fibers. Plant J,1996,9: 421-430.
[52]Schwarzacher T, Anamthawat-Jonsson K, Harrison G E, IslamA K M R,JiaJ Z, King I P, Leitch A R, Miller T E, Reader S M, Rogers W J, Shi M, Heslop-HarrisonJ S. Genomic in situ hybridization to identify alien chromosomes and chromosome segments in wheat. Theo Appl Genet,1992,84:778-786.
[53]Islam-Faridi M N, Mujeeb-Kazi A. Visualizationof Secale cereale DNA in wheat germplasm by FISH. Theor Appl Genet,1995,90:595-600.
[54]陈瑞阳，宋文芹,李秀兰.植物染色体标本制停车场的去壁、低渗法及其在细胞遗传学中的意义.遗传学报,1982,9(2)：151-159.
[55]Hasterok R, Wolny E, Hosiawa M, Kowalczyk M, et al. Comparative analysis of rDNA distribution in chromosomes of various species of Brassicaceae. Annals of Botany,2006,97(2):205-216.
[56]Wang C J, Harper L and Cande W Z. High-resolution single-copy gene fluorescence in situ hybridization and its use in the construction of a cytogenetic map of maize chromosome 9. Plant Cell,2006,18:529-544.
[57]Yang K, Qi H Y, Zhu L Q, Wang X J. Localization of S genes on extended DNA fibers (EDFs) in Brassica oleracea by high-resolution FISH. Acta Genet Sin,2006,33(3):277-284.
[58]钟筱波,Fransz P F, Wennekes J, vanKammen J A, de Jong H, Zabel P.在植物粗线期染色体和DNA纤维上的荧光原位杂交技术.遗传学报,1998,25(2)：142-149.
[59]Kato A. An improved method for chromosome counting in maize. Biotech Histochem,1997,72(5):249-52.
[60]Adeleke MTV, Pillay M, Okoli B E. An improved method for examining meiotic chromosomes in Musa L. Hortscience,2002,37(6):959-961.
[61]Martinez-Gomez P, Sanchez-Perez R, Vaknin Y, Dicenta F, Gradziel T M. Improved technique for counting chromosomes in almond. Scientia Horticulturae,2005,105(1):139-143.
[62]Parra L and Windle B. High resolution visual mapping of stretehed DNA by fluorescence in hybridization. Nature Genet,1993,5:17-21.
[63]Bensimon A and CremerT. High-resolution comparative hybridization to combed DNA fibers. Hum Genet, 1997,99:374-380.
[64]Heiskanen M, Karhu R, Hellsten E et al. High resolution mapping using fluorescence in situ hybridization to extended DNA fibers prepared from agarose-embeded cells. Biotechni-ques,1999,17:928-933.
[65]Miehalet X, Ekong R, Fougerousse F. Dynamic Molecular combing:Stretehing theWhole Human Genome for High-Resolution Studies. Seience,1997,277(5):1518-1523.
[66]Mesbah M, Wennekes-van eden J, de Jong J H. FISH to mitotic chromosomes and extended DNA fibres of Beta proeumbens in aseries of monosomic addition to beet (B.vulgaris). Chromosome Researeh,2000,8:285-293.
[67]Liao X B, Clemens K R, Tennant L, Wright P E, Gottesfeld J M. Specific interaction of the first three zinc fingers of TFIIIAwith the internal control region of the Xenopus 5S RNAgene. J Mol Biol,1992,223:857-871.
[68]Pieler T, Hamm J and Roeder R G. The 5S gene internal control region is composed of three distinct sequence elements, organized as two functional domains with variable spacing. Cell,1987,48:91-100.
[69]Cloix C, Tutois S, Mathieu O, Cuvillier C, Espagnol M C, Picard G, Tourmente S. Analysis of 5S rDNA arrays in Arabidopsis thaliana:physical mapping and chromosome-specific polymerPhisMs. Genome Res,2000,10: 679-690.
[70]Szymanski M, Barciszewska M Z, et al.5S Ribosomal RNA Database. Nucleic Acids Res,2002,30:176-178.
[71]Gerlach W L and Dyer T A. Sequence organization of the repeating units in the nucleus of wheat which contain 5S rRNA genes. Nucleic Acids Res,1980,8:4851-4865.
[72]Baum B R and Appels R. Evolutionary change at the 5S rDNA loci of species in the Triticea. Plant Syst Evol, 1992,183:195-208.
[73]Bhatia S, Singh K, Jagannathan V and Lakshmikumaran M..Organization and sequence analysis of the 5S rRNA genes in Brassica campestris. Plant Sci,1993,92:47-55.
[74]Wang Y W, Tseng P F, Tai P Y, Chang C J. Phylogenetic position of Raphanus in relation to Brassica species based on 5S rRNA spacer sequence data. Bot. Bull. Acad. Sin,1998,39:153-160.
[75]Fransz P F, Stam M, Montijn B, Hoopen R T, Wiegant J, Kooter J M, Oud O and Nanninga N. Detection of single-copy genes and chromosome rearrangements in Petunia hybrida by fluorescence in situ hybridization. Plant J,1996,9:767-774.
[76]Lavania U C, Yamamoto M, Mukai Y. Extended chromatin and DNA fibers from active plant nuclei for high-resolution FISH. Journal of Histochemistry and Cytochemistry,2003,51:1249-1253.
[77]Lavania U C, Basu S, Srivatava S, Mukai Y, Lavania S. In situ chromosomal localization of rDNA sites in "Safed Musli" chlorophytum Ker-Gawl and their physical measurement by Fiber FISH. Journal of Heredity,2005, 96(2):1-6.
[78]Li Z Y, Huang S L, Jin W W, Song Y C, Li L J. Determination of copy number for 5S rDNA and centromeric sequence RCS2 in rice by Fiber-FISH. Chin Sci Bull,2002.47(3):214-217.
[79]Li Z Y, Qin R, J W W, Xiong Z Y, Song Y C. FISH analysis of pachytene chromosome and DNA fiber of telomere sequence in rice (Oryza sativa L.indica).Acta Genetica Sinica,2005,32(8):832-836.
[80]Valarik M, Bartos J, Kovarova P, Kubalakova M, de Jong J H, Dolezel J. High-resolution FISH on super-stretched flow-sorted plant chromosomes. The Plant Journal,2004,37:940-950.
[81]Murata M, Heslop-Harrison J S, Motoyoshi F. Physical mapping of the 5S ribosomal RNA genes in Arabidopsis thaliana by multicolor fluorescence in situ hybridization with cosmid clones. The Plant Journal,1997,12:31-37.
[82]Fransz P, Armstrong S J, Alonso-Blanco C, Fisher T C, Torres-Ruiz R A, Jones G. Cytogenetics for the model system Arabidopsis thaliana. The Plant Journal,1998,13:867-876.
[83]Snowdon R J, Friedrich T, Friedt W, kohler W. Identifying the chromosomes of the A-and C-genome diploid Brassica species B. rapa (syn. campestris) and B. oleraceain their amphidiploid B. napus. Theoretical and Applied Genetics,2002,104:533-538.
[84]Hoda B M, Martin A, Schubert. Chromosomal localization of rDNA in the Brassicaceae. Genome,2005,48: 341-346.
[85]Levan A, Fedga K, Sandberg A A. Nomenclature for centromeric position on chromosome. Hereditas,1964,52 (2):201-220.
[86]Fukui K, Nakayama S, Ohmido N, Yoshiaki H, Yamabe M. Quantitative karyotyping of three diploid Brassica species by imaging methods and localization of 45 s rDNA loci on the identified chromosomes. Theoretical and Applied Genetic,1998,96:325-330.
[87]Morinaga T. Interspecific hybridisation in Brassica. VI. The cytology of Flhybrids of B. juncea and B. nigra. Cytologia,1934:6:62-67.
[88]U N. Genome analysis in Brassica with special reference to the experimental formation of B. napus and peculiar mode of fertilisation. J Japan Bot,1935,7:389-452.
[89]ROBbelen G. Beitrage zur Analyse des Brassica-Genoms. Chromosoma,1960,11:205-228.
[90]Olin-Fatih M, Heneen W G. C-banded karyotypes of Brassica campestrisB.oleracea, B.napus. Genome,1992, 35:283-289.
[91]Cheng B F, Heneen W K, Chen B Y. Mitotic karyotypes of Brassica campestris and Brassica alboglabra and identification of the B. alboglabra in an addition line. Genome,1995,38:313-319.
[92]Sastri D C, Hilu K, Appels R, Lagudah E S, Playford J, Baum B R. An overview of evolution in plant 5S DNA. Plant Systematics and Evolution,1992,183:169-181.
[93]Wang X H, Luo Peng. Studies on the karyotypes and C-banding partterns of Chinese kale (Brassica albolabra) and cabbage (B. oleracea var. capitata). Acta Botanica Sinica,1987,29(2):149-155.
[94]Snowdon R J, Friedrich T, Friedt W, kohler W. Identifying the chromosomes of the A-and C-genome diploid Brassica species B.rapa (syn. campestris) and B.oleraceain their amphidiploid B.napus. Theoretical and Applied Genetics,2002,104:533-538.
[95]Xuan S X, Shen S X, Zhao J J, Zhang C H, Chen X P, Qie L J. Location of 25S rDNA and 5S rDNA in Chinese Cabbage-pe-tsai Metaphase Chromosome. Scientia Agricultura Sinica,2007,40(4):782-787.
[96]Schrader O, Budahn H, Ahne R. Detection of 5S and 25S rRNA genes in Sinapis alba, Raphanus sativus and Brassica napus by double fluorescence in situ hybridization. Theoretical and Applied Genetics,2000,100: 665-669.
[97]Hasterok R, Maluszynska J. Nucleolar dominance does not occur in root tip cells of allotetraploid Brassica species. Genome,2000,43:574-579.
[98]Liu Y, Wang C. Origin, Classification and Evolution of Brassica oleracea L. Northern Horticulture,2006,4: 58-60.
[99]Liao D. Gene conversion drives within genic sequences:concerted evolution of ribosomal RNA genes in bacteria and archaea. Journal of Molecular Evolution,2000,51:305-317.
[100]Rong X Y, Zhu L Q, Wang Y, Gao Q G, Chen X D, Yang Y, Wang X J. Localization of MLPK and SSP genes for self-Incompatibility of Brassica oleracea by fluorescence in situ hybridization. Acta Agronomica Sinica,2009, 35(5):802-808.
[101]Campell B R, Song Y, Posch T E, Cullis C A, Town C D. Sequence and organization of 5S ribosomal RNA-encoding genes of Arabidopsis thaliana. Gene,1992,112:225-228.
[102]Rijke F M, Florijn R J, Tanke H J and Raap A K. DNA Fiber-FISH Staining Mechanism. Histochemistry and Cytochemistry,2002,48(6):743-745.
[103]Frans M, Florijn R J,Tanke H J, Raap A K. DNA Fiber-FISH staining mechanism. Journal of Histochemistry and Cytochemistry,2000,48:743-746.
[104]Pennisi E. A bonanza for plant genomics. Science,1998,282:652-654.
[105]Sebastian R L, Howell E C, King G J, Marshall D F and Kearsey M J. An integrated AFLP and RFLP Brassica oleracea linkage map from two morphologically distinct doubled-haploid mapping populations. Theor Appl. Genet,2000,100:75-81.
[106]Kunzel G, Korzun L and Meister A. Cytologically integrated physical restriction fragment length polymorphism maps for the barley genome based on translocation breakpoints. Genetics,2000,154:397-412.
[107]Islam-Faridi M N, Childs K L, Klein P E, Hodnett G, Menz M A, Klein R R, Rooney W L, Mullet J E, Stelly D M and Price H J. A molecular cytogenetic map of sorghum chromosome 1. Fluorescence in situ hybridization analysis with mapped bacterial artificial chromosomes. Genetics,2002,161:345-353.
[108]Koumbaris G L and Bass H W. A new single-locus cytogenetic mapping system for maize (Zea mays L.): Overcoming FISH detection limits with marker-selected sorghum (S. propinquum L.) BAC clones. Plant J,2003, 35:647-659.
[109]Fransz P F, Stam M, Montijn B, Hoopen R T, Wiegant J, Kooter J M, Oud O and Nanninga N. Detection of single-copy genes and chromosome rearrangements in Petunia hybrida by fluorescence in situ hybridization. Plant J,1996,9:767-774.
[110]Dong F, Song J, Naess S K, Helgeson J P and Gebhardt C. Development and applications of a set of chromosome-specific cytogenetic DNA markers in potato. Theor. Appl. Genet,2000,101:1001-1007.
[111]Gustafson J P, Dille J E. The chromosome location of Oryza sativa recombination linkage group. Proc Nat Acad Sci USA,1992,89:8646-8650.
[112]Fuchs J, Schubert I. Localization of seed protein genes on metaphase chromosomes of Vicia faba via fluorescence in situ hybridization. Chromosome Research,1995,3:94-100.
[113]Hanson R E, Zwick M S, Choi S, Islam-Faridi M N and Mcknight T D. Fluorescent in-situ hybridization of a bacteria] artificial chromosome. Genome,1995,38:646-651.
[114]Ohmido N, Akiyama Y and FukuiK. Physical mapping of unique nucleotide sequences on identified rice chromosomes. Plant Mol. Biol,1998,38:1043-1052.
[115]Lagercrantz U. Comparative mapping between Arabidopsis thaliana and Brassica nigra indicates that Brassica genomes have evolved through extensive genome replication accompanied by chromosomal fusions and frequent rearrangements. Genetics,1998,150:1217-1228.
[116]Ryder C D, Smith L B, Teakle G R and G J, King. Contrasting genome organisation:two regions of the Brassica oleracea genome compared with collinear regions of the Arabidopsis thaliana genome. Genome,2001, 44:808-817.
[117]Jackson S, Cheng A Z, Wang M L, Goodman H M and Jiang J. Comparative fluorescence in situ hybridization mapping of a 431-kb Arabidopsis thaliana bacterial artificial chromosome contig reveals the role of chromosome duplications in the expansion of the Brassica rapa genome. Genetics,2000,156:833-838.
[118]Kamisugi Y, Nakayama S, ONeil C M, Mathias R J, Trick M, Fukui K. Visualization of the Brassica self-incompatibility S-locus on identified oilseed rape chromosomes. Plant Mol. Biol.1998,38:1081-1087.
[2]Stebbins G L.Chromosome evolution in higher plants. London:Edward Arnold,1971.
[3]周雪雁,关伟军,马月辉,刘佳林.染色体显带技术及其在生物学研究中的意义.上海畜牧兽牧通讯,2004,5：2-3.
[4]Endo T R. Complete identification of common wheat chromosomes by means of the c-banding technique. Genetics,1986,61-93.
[5]王晓惠,罗鹏.芥蓝和结球甘蓝染色体组型及C-带带型的研究.植物学报,1987,29(2)：149-155.
[6]Armstrong S J, Fransz P, Marshall D F and Jones G H. Physical mapping of DNA repetitive sequences to mitotic and meiotic chromosomes of Brassica oleracea var.alboglabra by fluorescence in situ hybridization. Heredity, 1998,81:666-673.
[7]Howell E C, Barker G C, Jones G H, Kearsey M J, King G J, Kop E P, Ryder C D, Teakle G R, Vicente J G and Armstrong S J. Integration of the cytogenetic and genetic linkage maps of Brassica oleracea. Genetics,2002,161: 1225-1234.
[8]工太霞,吴春红,黄进勇,魏文辉.甘蓝rDNA及Cotl DNA荧光原位杂交及其核型分析.武汉大学学报(理学版),2006,52(2)：230-230.
[9]陈晓丹,朱利泉,王永,荣小营等.芸(?)属A基因组DNA封阻下的甘蓝C染色体组核型分析.农业生物技术学报,2009,17(3)：504-509.
[10]Charlesworth D, Vekemans X, Castric V and Glemin S. Plant self-incompatibility systems:a molecular evolutionary perspective. New Phytologist,2005,168:61-69.
[11]Franklin F C H, Lawrence M J and Franklin-Tong V E. Cell and molecular biology of self-incompatibility in flowering plants. Int. Rev. Cytol,1995,158:1-64.
[12]McClure B A, Haring V, Ebert P R, Anderson M A, Simpson R J, Sakiyama F and Clarke A E. Style selfincompatibility gene products of Nicotiana alata are ribonucleases. Nature,1989,342:955-957.
[13]Franklin-Tong V E and Franklin F C H. The different mechanisms of gametophytic self-incompatibility. Philos. Trans. R. Soc. Lond. B. Biol. Sci.2003,358(1434):1025-1032.
[14]Sijacic P, Wang X, Skirpan A L, Wang Y, Dowd P E, McCubbin A G, Huang S, and Kao T. Identification of the pollen determinant of S-RNase-mediated self-incompatibility. Nature,2004,429:302-305.
[15]Foote H C, Ride J P, Franklin-Tong V E, Walker E A, Lawrence M J, Franklin F C. Cloning and expression of a distinctive class of self-incompatibility (S) gene from Papaver rhoeas L. Proc Natl Acad Sci. USA,1994,91: 2265-69
[16]Franklin-Tong V E, Ride J P, Read N D, Trewawas A J and Franklin F C H. The self-incompatibility response in Papaver rhoeas is mediated by cytosolic free calcium. Plant J,1993,4:163-177.
[17]Franklin-Tong V E, Hackett G and Hepler P K. Ratioimaging of Ca21 in the self-incompatibility response in pollen tubes of Papaver rhoeas. Plant J,1997,12:1375-1386.
[18]Franklin-Tong V E, Holdaway-Clarke T L, Straatman K R, Kunkel J G and Hepler P K. Involvement of extracellular calcium influx in the self-incompatibility response of Papaver rhoeas. Plant J,2002,29:333-345.
[19]Rudd J J, Franklin F C H, Lord J M and Franklin-Tong V E. Increased phosphorylation of a 26-kD pollen protein is induced by the self-incompatibility response in Papaver rhoeas. Plant Cell,1996,8:713-724.
[20]Snowman B N, Kovar D R, Shevchenko G, Franklin-Tong V E and Staiger C J. Signal-mediated depolymerization of actin in pollen during the self-incompatibility response. Plant Cell,2002,14:2613-2626.
[21]Thomas S G and Franklin-Tong V E. Self-incompatibility triggers programmed cell death in Papaver pollen. Nature,2004,429:305-309.
[22]Goodwillie C. The genetic control of self-incompatibility in Linanthus parviflorus (Polemoniaceae). Heredity, 1997,79:424-432.
[23]Hiscock S J, and Tabah D A.The different mechanisms of sporophytic self-incompatibility. Philos. Trans. R. Soc. Lond. B. Biol. Sci,2003,358(1434):1037-1045.
[24]Schopfer C R, Nasrallah M E and Nasrallah J B. The male determinant of self-incompatibility in Brassica..Science,1999,266:1697-1700.
[25]Takayama S, Shiba H, Iwano M, Shimosato H,. Che F-S, Kai N, Watanabe M, Suzuki G, Hinata K andlsogai A. The pollen determinant of self-incompatibility in Brassica campestris. Proc. Natl Acad. Sci USA,2000,97: 1920-1925.
[26]Stein J C, Howlett B, Boyes D C, NasrallahM E and Nasrallah J B. Molecular cloning of a putative receptor kinase gene encoded by the self-incompatibility locus of Brassica oleracea. Proc. Natl Acad. Sci. USA,1991,88: 8816-8820.
[27]Nasrallah J B and Nasrallah M E. Pollen-stigma signalling in the sporophytic self-incompatibility response. Plant Cell,1993,5:1325-1335.
[28]Takayama S, Shimosato H, Shiba H, Funato M, Che F E, Watanabe M, Iwano M and Isogai A. Direct ligand-receptor complex interaction controls Brassica self-incompatibility. Nature,2001,413:534-538.
[29]Murase K, Shiba H, Iwano M, Che F S, Watanabe M, Isogai A and Takayama S. A membrane-anchored protein kinase involved in Brassica self-incompatibility signaling. Science,2004,303(5663):1516-9.
[30]Harper L C, Cande W Z. Mapping a new frontier:development of integrated cytegenetic maps in plants. Funct integr Genomic,2000,1:89-98.
[31]Wang C J and Chen C C. Cytogenetic mapping in maize Cytogenet. Genome Res,2005,109:63-69.
[32]McClintock B. The relation of homozygous deficiencies to mutations and allelic series in maize. Genetics,1944, 29:478-502.
[33]Weber D and Helentjaris T. Mapping RFLP loci in maize using B-A translocations. Genetics,1989,121: 583-590.
[34]Kunzel G, Korzun L and Meister A. Cytologically integrated physical restriction fragment length polymorphism maps for the barley genome based on translocation breakpoints. Genetics,2000,154:397-412.
[35]Zhong X B, Bodeau J, Fransz P F, Williamson V M, van Kammen A, de Jong J H and Zabel P. FISH to meiotic pachytene chromosomes of tomato locates the root-knot nematode resistance gene Mi-1 and the acid phosphatase gene Aps-1 near the junction of euchromatin and pericentromeric heterochromatin of chromosome arms 6S and 6L, respectively. Theor. Appl. Genet,1999,98:365-370.
[36]Fransz P F, Armstrong S, de Jong J H, Parnell L D, van Drunen C, Dean C, Zabel P, Bisseling T and Jones G H. Integrated cytogenetic map of chromosome arm 4S of A. thaliana:Structural organization of heterochromatic knob and centromere region. Cell,2000,100:367-376.
[37]Cheng Z, Buell C R, Wing R A, Gu M and Jiang J. Toward a cytological characterization of the rice genome. Genome Res,2001,11:2133-2141.
[38]Kulikova O, Gualtieri G, Geurts R, Kim D J, Cook D, Huguet T, de Jong J H, Fransz P F and Bisseling T. Integration of the FISH pachytene and genetic maps of Medicago truncatula. Plant J,2001,27:49-58.
[39]Howell E C, Barker G C, Jones G H, Kearsey M J, King G J, Kop E P, Ryder C D, Teakle G R, Vicente J G and Armstrong S J. Integration of the cytogenetic and genetic linkage maps of Brassica oleracea. Genetics,2002,161: 1225-1234.
[40]Islam-Faridi M N, Childs K L, Klein P E, Hodnett G, Menz M A, Klein R R, Rooney W L, Mullet J E, Stelly D M and Price H J. A molecular cytogenetic map of sorghum chromosome 1. Fluorescence in situ hybridization analysis with mapped bacterial artificial chromosomes. Genetics,2002,161:345-353.
[41]Koumbaris G L and Bass H W. A new single-locus cytogenetic mapping system for maize (Zea mays L.): Overcoming FISH detection limits with marker-selected sorghum (S. propinquum L.) BAC clones. Plant J,2003, 35:647-659.
[42]Wang C R, Harper L, Cande W Z. High-Resolution Single-Copy Gene Fluorescence in Situ Hybridization and Its Use in the Construction of a Cytogenetic Map of Maize Chromosome 9. The Plant Cell,2006,18:529-544.
[43]Li L-J, Song Y-C, Yan H-M, Liu L-H. Chromosome location of two RFLP markers umc22 and umcl22 tightly linked to the Htl gene in maize. Acta Bot Sin,1998,40:1093-1097.
[44]Wang L, Song Y-C, Ning S-B, Li L-J, Liu L-H, Gu M-Q Guo L-Q. Identification of Zea diploperennis chromatins introgressed to maize via genomic in situ hybridization. Acta Bot Sin,1999,41:1264-1268.
[45]Nath J, Johnson K L. Fluorescence in situ hybridization (FISH):DNA probe production and hybridization criteria. Biotech Histochem,1998,73:6-22.
[46]Gall J and Pardue M. Formation and detection of RNA · DNA hybrid molecules in cytological preparations. Proc. Natl. Acad. Sci USA,1969,63:378-383.
[47]Langer P R, Waldrop A A and Ward D C. Enzymatic synthesis of biotin-labeled polynucleotides:Novel nucleic acid affinity probes. Proc.Natl. Acad. Sci USA,1981,78:6633-6637.
[48]Rayburn A L, Gill B S.Use of biotin-labeled probes to map specific DNA sequences on wheat chromosomes. J Hered,1985,76:78-81.
[49]De Jong J H, Fransz P F, Zabel P. High resolution FISH in plants techniques and applications. Trends Plant Sci, 1999,4:258-263.
[50]Jiang J and Gill B S.New 18S.26S ribosomal RNA gene loci:chromosomal landmarks for the evolution of polyploid wheats. Chromosoma,1994,103:179-185.
[51]Fransz P F, Alonso2Blanco C, Liharska T B, PeetersA J M, Zabel P et al. High-resolution physical mapping in A rabidopsis thaliana and tomato by fluorescence in situ hybridization to extended DNA fibers. Plant J,1996,9: 421-430.
[52]Schwarzacher T, Anamthawat-Jonsson K, Harrison G E, IslamA K M R,JiaJ Z, King I P, Leitch A R, Miller T E, Reader S M, Rogers W J, Shi M, Heslop-HarrisonJ S. Genomic in situ hybridization to identify alien chromosomes and chromosome segments in wheat. Theo Appl Genet,1992,84:778-786.
[53]Islam-Faridi M N, Mujeeb-Kazi A. Visualizationof Secale cereale DNA in wheat germplasm by FISH. Theor Appl Genet,1995,90:595-600.
[54]陈瑞阳，宋文芹,李秀兰.植物染色体标本制停车场的去壁、低渗法及其在细胞遗传学中的意义.遗传学报,1982,9(2)：151-159.
[55]Hasterok R, Wolny E, Hosiawa M, Kowalczyk M, et al. Comparative analysis of rDNA distribution in chromosomes of various species of Brassicaceae. Annals of Botany,2006,97(2):205-216.
[56]Wang C J, Harper L and Cande W Z. High-resolution single-copy gene fluorescence in situ hybridization and its use in the construction of a cytogenetic map of maize chromosome 9. Plant Cell,2006,18:529-544.
[57]Yang K, Qi H Y, Zhu L Q, Wang X J. Localization of S genes on extended DNA fibers (EDFs) in Brassica oleracea by high-resolution FISH. Acta Genet Sin,2006,33(3):277-284.
[58]钟筱波,Fransz P F, Wennekes J, vanKammen J A, de Jong H, Zabel P.在植物粗线期染色体和DNA纤维上的荧光原位杂交技术.遗传学报,1998,25(2)：142-149.
[59]Kato A. An improved method for chromosome counting in maize. Biotech Histochem,1997,72(5):249-52.
[60]Adeleke MTV, Pillay M, Okoli B E. An improved method for examining meiotic chromosomes in Musa L. Hortscience,2002,37(6):959-961.
[61]Martinez-Gomez P, Sanchez-Perez R, Vaknin Y, Dicenta F, Gradziel T M. Improved technique for counting chromosomes in almond. Scientia Horticulturae,2005,105(1):139-143.
[62]Parra L and Windle B. High resolution visual mapping of stretehed DNA by fluorescence in hybridization. Nature Genet,1993,5:17-21.
[63]Bensimon A and CremerT. High-resolution comparative hybridization to combed DNA fibers. Hum Genet, 1997,99:374-380.
[64]Heiskanen M, Karhu R, Hellsten E et al. High resolution mapping using fluorescence in situ hybridization to extended DNA fibers prepared from agarose-embeded cells. Biotechni-ques,1999,17:928-933.
[65]Miehalet X, Ekong R, Fougerousse F. Dynamic Molecular combing:Stretehing theWhole Human Genome for High-Resolution Studies. Seience,1997,277(5):1518-1523.
[66]Mesbah M, Wennekes-van eden J, de Jong J H. FISH to mitotic chromosomes and extended DNA fibres of Beta proeumbens in aseries of monosomic addition to beet (B.vulgaris). Chromosome Researeh,2000,8:285-293.
[67]Liao X B, Clemens K R, Tennant L, Wright P E, Gottesfeld J M. Specific interaction of the first three zinc fingers of TFIIIAwith the internal control region of the Xenopus 5S RNAgene. J Mol Biol,1992,223:857-871.
[68]Pieler T, Hamm J and Roeder R G. The 5S gene internal control region is composed of three distinct sequence elements, organized as two functional domains with variable spacing. Cell,1987,48:91-100.
[69]Cloix C, Tutois S, Mathieu O, Cuvillier C, Espagnol M C, Picard G, Tourmente S. Analysis of 5S rDNA arrays in Arabidopsis thaliana:physical mapping and chromosome-specific polymerPhisMs. Genome Res,2000,10: 679-690.
[70]Szymanski M, Barciszewska M Z, et al.5S Ribosomal RNA Database. Nucleic Acids Res,2002,30:176-178.
[71]Gerlach W L and Dyer T A. Sequence organization of the repeating units in the nucleus of wheat which contain 5S rRNA genes. Nucleic Acids Res,1980,8:4851-4865.
[72]Baum B R and Appels R. Evolutionary change at the 5S rDNA loci of species in the Triticea. Plant Syst Evol, 1992,183:195-208.
[73]Bhatia S, Singh K, Jagannathan V and Lakshmikumaran M..Organization and sequence analysis of the 5S rRNA genes in Brassica campestris. Plant Sci,1993,92:47-55.
[74]Wang Y W, Tseng P F, Tai P Y, Chang C J. Phylogenetic position of Raphanus in relation to Brassica species based on 5S rRNA spacer sequence data. Bot. Bull. Acad. Sin,1998,39:153-160.
[75]Fransz P F, Stam M, Montijn B, Hoopen R T, Wiegant J, Kooter J M, Oud O and Nanninga N. Detection of single-copy genes and chromosome rearrangements in Petunia hybrida by fluorescence in situ hybridization. Plant J,1996,9:767-774.
[76]Lavania U C, Yamamoto M, Mukai Y. Extended chromatin and DNA fibers from active plant nuclei for high-resolution FISH. Journal of Histochemistry and Cytochemistry,2003,51:1249-1253.
[77]Lavania U C, Basu S, Srivatava S, Mukai Y, Lavania S. In situ chromosomal localization of rDNA sites in "Safed Musli" chlorophytum Ker-Gawl and their physical measurement by Fiber FISH. Journal of Heredity,2005, 96(2):1-6.
[78]Li Z Y, Huang S L, Jin W W, Song Y C, Li L J. Determination of copy number for 5S rDNA and centromeric sequence RCS2 in rice by Fiber-FISH. Chin Sci Bull,2002.47(3):214-217.
[79]Li Z Y, Qin R, J W W, Xiong Z Y, Song Y C. FISH analysis of pachytene chromosome and DNA fiber of telomere sequence in rice (Oryza sativa L.indica).Acta Genetica Sinica,2005,32(8):832-836.
[80]Valarik M, Bartos J, Kovarova P, Kubalakova M, de Jong J H, Dolezel J. High-resolution FISH on super-stretched flow-sorted plant chromosomes. The Plant Journal,2004,37:940-950.
[81]Murata M, Heslop-Harrison J S, Motoyoshi F. Physical mapping of the 5S ribosomal RNA genes in Arabidopsis thaliana by multicolor fluorescence in situ hybridization with cosmid clones. The Plant Journal,1997,12:31-37.
[82]Fransz P, Armstrong S J, Alonso-Blanco C, Fisher T C, Torres-Ruiz R A, Jones G. Cytogenetics for the model system Arabidopsis thaliana. The Plant Journal,1998,13:867-876.
[83]Snowdon R J, Friedrich T, Friedt W, kohler W. Identifying the chromosomes of the A-and C-genome diploid Brassica species B. rapa (syn. campestris) and B. oleraceain their amphidiploid B. napus. Theoretical and Applied Genetics,2002,104:533-538.
[84]Hoda B M, Martin A, Schubert. Chromosomal localization of rDNA in the Brassicaceae. Genome,2005,48: 341-346.
[85]Levan A, Fedga K, Sandberg A A. Nomenclature for centromeric position on chromosome. Hereditas,1964,52 (2):201-220.
[86]Fukui K, Nakayama S, Ohmido N, Yoshiaki H, Yamabe M. Quantitative karyotyping of three diploid Brassica species by imaging methods and localization of 45 s rDNA loci on the identified chromosomes. Theoretical and Applied Genetic,1998,96:325-330.
[87]Morinaga T. Interspecific hybridisation in Brassica. VI. The cytology of Flhybrids of B. juncea and B. nigra. Cytologia,1934:6:62-67.
[88]U N. Genome analysis in Brassica with special reference to the experimental formation of B. napus and peculiar mode of fertilisation. J Japan Bot,1935,7:389-452.
[89]ROBbelen G. Beitrage zur Analyse des Brassica-Genoms. Chromosoma,1960,11:205-228.
[90]Olin-Fatih M, Heneen W G. C-banded karyotypes of Brassica campestrisB.oleracea, B.napus. Genome,1992, 35:283-289.
[91]Cheng B F, Heneen W K, Chen B Y. Mitotic karyotypes of Brassica campestris and Brassica alboglabra and identification of the B. alboglabra in an addition line. Genome,1995,38:313-319.
[92]Sastri D C, Hilu K, Appels R, Lagudah E S, Playford J, Baum B R. An overview of evolution in plant 5S DNA. Plant Systematics and Evolution,1992,183:169-181.
[93]Wang X H, Luo Peng. Studies on the karyotypes and C-banding partterns of Chinese kale (Brassica albolabra) and cabbage (B. oleracea var. capitata). Acta Botanica Sinica,1987,29(2):149-155.
[94]Snowdon R J, Friedrich T, Friedt W, kohler W. Identifying the chromosomes of the A-and C-genome diploid Brassica species B.rapa (syn. campestris) and B.oleraceain their amphidiploid B.napus. Theoretical and Applied Genetics,2002,104:533-538.
[95]Xuan S X, Shen S X, Zhao J J, Zhang C H, Chen X P, Qie L J. Location of 25S rDNA and 5S rDNA in Chinese Cabbage-pe-tsai Metaphase Chromosome. Scientia Agricultura Sinica,2007,40(4):782-787.
[96]Schrader O, Budahn H, Ahne R. Detection of 5S and 25S rRNA genes in Sinapis alba, Raphanus sativus and Brassica napus by double fluorescence in situ hybridization. Theoretical and Applied Genetics,2000,100: 665-669.
[97]Hasterok R, Maluszynska J. Nucleolar dominance does not occur in root tip cells of allotetraploid Brassica species. Genome,2000,43:574-579.
[98]Liu Y, Wang C. Origin, Classification and Evolution of Brassica oleracea L. Northern Horticulture,2006,4: 58-60.
[99]Liao D. Gene conversion drives within genic sequences:concerted evolution of ribosomal RNA genes in bacteria and archaea. Journal of Molecular Evolution,2000,51:305-317.
[100]Rong X Y, Zhu L Q, Wang Y, Gao Q G, Chen X D, Yang Y, Wang X J. Localization of MLPK and SSP genes for self-Incompatibility of Brassica oleracea by fluorescence in situ hybridization. Acta Agronomica Sinica,2009, 35(5):802-808.
[101]Campell B R, Song Y, Posch T E, Cullis C A, Town C D. Sequence and organization of 5S ribosomal RNA-encoding genes of Arabidopsis thaliana. Gene,1992,112:225-228.
[102]Rijke F M, Florijn R J, Tanke H J and Raap A K. DNA Fiber-FISH Staining Mechanism. Histochemistry and Cytochemistry,2002,48(6):743-745.
[103]Frans M, Florijn R J,Tanke H J, Raap A K. DNA Fiber-FISH staining mechanism. Journal of Histochemistry and Cytochemistry,2000,48:743-746.
[104]Pennisi E. A bonanza for plant genomics. Science,1998,282:652-654.
[105]Sebastian R L, Howell E C, King G J, Marshall D F and Kearsey M J. An integrated AFLP and RFLP Brassica oleracea linkage map from two morphologically distinct doubled-haploid mapping populations. Theor Appl. Genet,2000,100:75-81.
[106]Kunzel G, Korzun L and Meister A. Cytologically integrated physical restriction fragment length polymorphism maps for the barley genome based on translocation breakpoints. Genetics,2000,154:397-412.
[107]Islam-Faridi M N, Childs K L, Klein P E, Hodnett G, Menz M A, Klein R R, Rooney W L, Mullet J E, Stelly D M and Price H J. A molecular cytogenetic map of sorghum chromosome 1. Fluorescence in situ hybridization analysis with mapped bacterial artificial chromosomes. Genetics,2002,161:345-353.
[108]Koumbaris G L and Bass H W. A new single-locus cytogenetic mapping system for maize (Zea mays L.): Overcoming FISH detection limits with marker-selected sorghum (S. propinquum L.) BAC clones. Plant J,2003, 35:647-659.
[109]Fransz P F, Stam M, Montijn B, Hoopen R T, Wiegant J, Kooter J M, Oud O and Nanninga N. Detection of single-copy genes and chromosome rearrangements in Petunia hybrida by fluorescence in situ hybridization. Plant J,1996,9:767-774.
[110]Dong F, Song J, Naess S K, Helgeson J P and Gebhardt C. Development and applications of a set of chromosome-specific cytogenetic DNA markers in potato. Theor. Appl. Genet,2000,101:1001-1007.
[111]Gustafson J P, Dille J E. The chromosome location of Oryza sativa recombination linkage group. Proc Nat Acad Sci USA,1992,89:8646-8650.
[112]Fuchs J, Schubert I. Localization of seed protein genes on metaphase chromosomes of Vicia faba via fluorescence in situ hybridization. Chromosome Research,1995,3:94-100.
[113]Hanson R E, Zwick M S, Choi S, Islam-Faridi M N and Mcknight T D. Fluorescent in-situ hybridization of a bacteria] artificial chromosome. Genome,1995,38:646-651.
[114]Ohmido N, Akiyama Y and FukuiK. Physical mapping of unique nucleotide sequences on identified rice chromosomes. Plant Mol. Biol,1998,38:1043-1052.
[115]Lagercrantz U. Comparative mapping between Arabidopsis thaliana and Brassica nigra indicates that Brassica genomes have evolved through extensive genome replication accompanied by chromosomal fusions and frequent rearrangements. Genetics,1998,150:1217-1228.
[116]Ryder C D, Smith L B, Teakle G R and G J, King. Contrasting genome organisation:two regions of the Brassica oleracea genome compared with collinear regions of the Arabidopsis thaliana genome. Genome,2001, 44:808-817.
[117]Jackson S, Cheng A Z, Wang M L, Goodman H M and Jiang J. Comparative fluorescence in situ hybridization mapping of a 431-kb Arabidopsis thaliana bacterial artificial chromosome contig reveals the role of chromosome duplications in the expansion of the Brassica rapa genome. Genetics,2000,156:833-838.
[118]Kamisugi Y, Nakayama S, ONeil C M, Mathias R J, Trick M, Fukui K. Visualization of the Brassica self-incompatibility S-locus on identified oilseed rape chromosomes. Plant Mol. Biol.1998,38:1081-1087.