摘要
采用流式细胞术,以人(Homo sapiens)淋巴细胞DNA含量(7.00pg/2C)为标准,以鱼的红血细胞为材料,测定中国6种重要经济鱼类条纹斑竹鲨(Chiloscyllium plagiosum)、斜带石斑鱼(Epinephelus coioides)、赤点石斑鱼(Epinephelus akaara)、大黄鱼(Pseudosciaena crocea)、中华乌塘鳢(Bostrichthys sinensis)、大菱鲆(Scophthalmus maximus)的基因组大小(C-值)。结果显示,这6种经济鱼类的单倍体DNA含量分别为:条纹斑竹鲨(4.91±0.24)pg;斜带石斑鱼(1.25±0.04)pg;赤点石斑鱼(1.23±0.11)pg;大黄鱼(0.76±0.03)pg;中华乌塘鳢(0.85±0.04)pg;大菱鲆(0.65±0.01)pg。研究结果可为这6种经济鱼类的种质鉴定提供依据。此外,根据本研究的实验结果并结合其他鱼类的基因组大小资料,对鱼类基因组大小与其染色体数目及进化地位之间的相关性进行了探讨,对比分析显示,鱼类进化地位越高则DNA含量越少,同时鱼类基因组的大小差异存在复杂性,并不完全与染色体数目相关。本研究还就鱼类基因组大小的测定方法等问题提出建议,认为应采用流式细胞术和人淋巴细胞作为规范的检测方法和对照标准。
The study of the genome size is highly significant as it can not only help to instruct the hybridization and breeding program,but also aid to the whole-genome sequencing project of commercial fishes. Chiloscyllium plagiosum,Epinephelus coioides,E. akaara,Pseudosciaena crocea,Bostrichthys sinensis and Scophthalmus maximus,with high market value,are commercially important and popular fishes in China because of their delicious and nutritious meat. In China,E. coioides,P. crocea and S. maximus have been the key of the aquaculture industry over a large scale. Nevertheless,there are still limited data of the genome size despite of many corresponding researches on the heredity,evolution and breeding. In this paper,the genome size（ C-value） of these fishes was determined using a flow cytometry technique,and Human（ Homo sapiens）lymphocyte（ 3.50 pg/C） was serving as an internal control. The results showed C-values are 4.91±0.24,1.25±0.04,1.23±0.11,0.76±0.03,0.85±0.04,and 0.65±0.01 for C. plagiosum,E. coioides,E. akaara,P. crocea,B. sinensis and S. maximus,respectively. The results showed that the genome size of the class Chondrichthyes was significantly larger than that of Osteichthyes,and the genome size was found significantly different among these fishes except for E. coioides and E. akaara,which are in the same genus and have an affinity relationship between them. The C-values may be used as a criterion for species identification among these fishes. Base on our results and other data from genome-size database which were measured using the same method and control,the relationship between C-values and evolution status and chromosome amount of the fishes was discussed. Most of the data showed that with the higher evolution status of the fish,the lower C-value is presented. To a certain extent,the result demonstrated that C-value prefers to be more condensed along with the evolution of the genome. However,there are many complex factors which can influence the genome size of the fish. The point of view that the genome size positively correlates to the amount of chromosome is not always correct according to the data. In the present study,the amount of chromosome of P. crocea and B. sinensis are 48 and 46 respectively,while their relative genome sizes are 0.76 pg and 0.85 pg. Furthermore,the result also shows that there is more diversity on the genome size among species existing in original order such as the Chondrichthyes and Acipenseriformes of the Osteichthyes,which may be due to an age long evolution history of this fish. Finally,in order to avoid the disadvantages of poor accuracy and low comparability,we consider that the use of the flow cytometry technique and human lymphocyte as a control should be a more appropriate criterion for genome size determination protocol.
出处
《中国水产科学》
CAS
CSCD
北大核心
2010年第4期689-694,共6页
Journal of Fishery Sciences of China
基金
国家自然科学基金项目(40976094)
