摘要
割手密作为甘蔗育种中重要的野生亲本,具有适应范围广、抗病和抗逆性强的优势。为了确定5S r DNA在不同倍性割手密基因组中的分布位点的数目、区域与拷贝数,本研究应用荧光原位杂交技术在云南82-114(2n=10x=80)和福建89-1-19(2n=13x=104)两份不同倍性割手密材料的间期核和中期染色体上进行5S r DNA定位研究。结果表明:5S r DNA在这两个割手密无性系中的位点数、分布位置以及信号的强弱变化较大。其中,云南82-114割手密有10个信号位点,且基本都在着丝粒附近;福建89-1-19割手密有13个信号位点,部分靠近着丝粒,还有少部分在着丝粒附近的长臂上;同一细胞中不同染色体上的杂交信号有强弱之分,差异明显;而且割手密的5S r DNA位点数与倍性具有相关性,在染色体上没有固定的分布模式,5S r DNA在不同染色体上的拷贝数存在较大的差异。研究结果揭示了割手密染色体结构多样性和5S r DNA拷贝数多样性,可在分子水平上为染色体提供有效的识别标记,有助于物种的进化及亲缘关系的分析。
As an important wild parental line in sugarcane breeding, Saccharum spontaneum(S. spontaneum) has good advantages of adapting to a wide range of surroundings and disease-resistant, strong resistance. The objective was to determine the number, location and copy number of 5S r DNA sites in the different ploidy S. spontaneum. The S. spontaneum chromosome localization of 5S r DNA was studied by fluorescence in situ hybridization on interphase nuclei and metaphase chromosomes of two different ploidy S. spontaneum materials, that is Yunnan82-114(2n=10x=80) and Fujian89-1-19(2n=13x=104). The results showed that the number of 5S r DNA site signal loci situation on chromosome and the intensity of the signal somewhat varied in the two S. spontaneums. Among them, ten 5S r DNA sites in tota1 were detected in Yunnan82-114, and occurred on the whole near the centromere region instead of the arms; Thirteen 5S r DNA sites in tota1 were detected in Fujian89-1-19, most occurred close to the centromere region, and a few located at the long arms near by the centromere region; Hybridization signals on different chromosomes in the same cell showing strong or weak obviously. The 5S r DNA loci was correlated with ploidy and its chromosomal distribution patterns were highly varied among the S. spontaneum materials, and there was a big difference in the copy number of 5S r DNA on different chromosomes. The results of this study revealed the diversity of chromosome structure and the 5S r DNA copy number of S. spontaneum. It has provided effective identification of chromosome at the molecular level, contributed to the evolution genetic relationship analysis of different species.
出处
《基因组学与应用生物学》
CAS
CSCD
北大核心
2015年第8期1761-1768,共8页
Genomics and Applied Biology
基金
国家甘蔗产业体系专项资金(CARS-20-1-5)
国家自然科学青年基金(31401440)共同资助
关键词
割手密
5SrDNA
染色体
倍性
荧光原位杂交
Saccharum spontaneum
5SrDNA
Chromosome
Ploidy
Fluorescent in situ hybridization
