鮸染色体的识别及核型特征分析
邹 禹,郑 娇,张 静,刘贤德,王志勇,蔡明夷*

(集美大学 水产学院,农业部东海海水健康养殖重点实验室,福建 厦门 361021)

; 核型; 荧光原位杂交; 核糖体DNA; 端粒序列

Chromosome Identification and Karyotype Characterization of Miichthys miiuy
ZOU Yu,ZHENG Jiao,ZHANG Jing,LIU Xiande,WANG Zhiyong,CAI Mingyi*

(The Key Laboratory of Healthy Mariculture for the East China Sea,Ministry of Agriculture,Fisheries College,Jimei University,Xiamen 361021,China)

Miichthys miiuy; karyotype; fluorescence in situ hybridization(FISH); ribosomal DNA; telomere sequence

DOI: 10.6043/j.issn.0438-0479.201709007

备注

(Miichthys miiuy)是我国南方重要的海水养殖种类.针对细胞遗传标记匮乏的问题,利用荧光染色、硝酸银染色(银染)、荧光原位杂交(FISH)等方法分析了的核型特征,发现的核型含24对端部着丝粒鮸染色体(2n=48t),鮸染色体经碘化丙啶(PI)染色后,荧光强度呈现特定的二维分布模式; 利用图像分析软件可转化为更直观的3D-光强度图,为鮸染色体的识别、配对提供了丰富的信息.18S rDNA和5S rDNA双色FISH结果显示,的18S rDNA和5S rDNA均只有1对位点,分别位于1号染色体的近着丝粒区域和2号染色体的着丝粒区域.银染显示的核仁组织区域(NOR)和4',6-二脒基-2-苯基吲哚(DAPI)染色显示的暗带,均与18S rDNA位点的位置相同.的端粒序列FISH信号分布于所有染色体的两端,未发现臂间端粒信号.综上,通过PI染色和图像分析软件解决了染色体识别困难的问题,并使用FISH方法分析了的核型特征,研究结果丰富了的细胞遗传学标记,也为研究石首鱼类染色体进化提供了基础数据.

Miichthys miiuy is an important mariculture species in southern China.The karyotypic characteristics of M. miiuy were analyzed with fluorescence staining,silver staining and fluorescence in situ hybridization(FISH).The results showed that the karyotype of M. miiuy had 24 pairs of centromeric chromosomes(2n=48t).After staining with propidium iodide(PI),the chromosomes showed a specific two-dimensional distribution pattern of fluorescence,which could be transformed into an intuitive 3D light intensity map using an image analysis software.Based on the two-dimensional distribution pattern of PI fluorescence,24 pairs of chromosomes of M. miiuy can be identified and paired more accurately.Moreover,the results of dual-FISH with rDNA probes showed that both 18S rDNA and 5S rDNA were single loci,located at the proximal on chromosome 1 and the centromere on chromosome 2,respectively.The nucleolar organizer regions(NOR)revealed with silver staining and the negative bands revealed with 4',6-diamidino-2-phenylindole(DAPI)staining were both located at the same position of 18S rDNA locus.FISH signals of the telomeric sequence were found at both ends of all chromosomes,but none was found at interstitial region.Above all,a method to assist chromosome identification based on PI staining and image analysis was proposed,and the karyotypic characteristics of M. miiuy were analyzed with FISH in this study,which provided essential basic data for further studies in genetics and breeding in Sciaenidae.