七种鲅亚科鱼Ag-NORs的比较研究

本文研究了红鳍鲅、青稍红鲅、蒙古红鲅、翘嘴红鲅、CAN条、团头鲂和长春鳊等7种鲅亚科鱼类的银染带。结果表明,在中期分裂相中各自的A g-NORs数在4-8个之间。综合分析比较国内已发表的鲤科银染资料,得出多数中国鲤科鱼类的Ag-NORs数为4位于两对sm染色体短臂端部。鲅亚科鱼在进化过程中NORs数目有增加的趋势。 Abstract:The Ag-NORs of 7 species in Abramidinae,namely Culter erythropterus,Erythroculter dabryi,E.ilishaeformis,E.mongolicus,Hemiculter leucisclus,Megalobrama amblycephala and Parabramis pekinensis were studied.The results showed that 4~8 Ag-NORs were observed in their metaphases respectively.Based on the Ag-NORs data of Cyprinid fishes published in China,we suggested that the number of Ag-NORs in major Chinese Cyprinidae is 4,locating on the short arm tips of two pairs smchromosomes.The trend of Ag-NORs number in Abramidinae fishes is towards increasing in course of evolution.     

应用FISH技术鉴定一个小冰麦易位系

以生物素（ｂｉｏｔｉｎ１６ｄＵＴＰ）标记的天蓝冰草（Ａｇｒｏｐｙｒｏｎｉｎｔｅｒｍｅｄｉｕｍ（Ｈｏｓｔ）Ｐ．Ｂ．＝Ｅｌｙｔｒｉｇｉａｉｎｔｅｒｍｅｄｉａ（Ｈｏｓｔ）Ｎｅｖｓｋｉ＝Ｔｈｉｎｏｐｙｒｕｍｉｎｔｅｒｍｅｄｉｕｍ（Ｈｏｓｔ）ＢａｒｋｗｏｒｔｈａｎｄＤｅｗｅｙ）染色体组ＤＮＡ为探针,普通小麦（ＴｒｉｔｉｃｕｍａｅｓｔｉｖｕｍＬ．）“中国春”ＤＮＡ为封闭,用荧光原位杂交（ＦＩＳＨ）技术对小冰麦３３号进行检测。结果表明：在一对染色体的端部显现出绿色荧光,这说明小冰麦３３号携带外源基因的冰草染色体片段位于小麦染色体端部,而且易位的染色体片段是较小的。从ＤＮＡ水平直接证明小冰麦３３是一个冰草染色体片段易位到小麦染色体端部的易位系。     

Characterization of a Wheat- wheatgrass Translocation Line by FISH

The genomic DNA of wheatgrass (Agropyron intermedium (Host) P.B. = Elytrigia intermedia (Host) Nevski = Thinopyrum intermedium (Host) Barkworth and Dewey) was labelled with biotin-16-dUTP as a probe, and genomic DNA of common wheat ( Triticum aestivum L. ) "Chinese Spring" was used for blocking. Wheat-wheatgrass line 33 was examined by fluorescence in situ hybridization (FISH) technique. The terminal regions of a pair of chromosomes showed green fluorescent signals. It has been concluded that chromosome segrnents containing alien genes of wheatgrass are located at the terminal regions of wheat chromosomes in wheat-wheatgrass line 33, and the translocated segments were small. Wheat-wheatgrass line 33 has been proved to be a translocation line with chromosome segments of wheatgrass translocated to the terminal regions of wheat chromoSomes.     

利用染色体涂染方法建立人和白眉长臂猿(Hylobates hoolock)的比较染色体图谱

除人Y染色体外,本文采用生物素标记的人全部整条染色体特异探针与白眉长臂猿(Hylobates hoolock)有丝分裂中期分裂相进行染色体原位杂交即染色体涂染法以研究人和白眉长臂猿染色体之间的同源性。在白眉长臂猿18对常染色体上检测出了与人22对常染色体同源的59对染色体片段,确定了人和白眉长臂猿之间的精度较高的染色体连锁群。结果表明:自人与白眉长臂猿的祖先分歧以来,大量的染色体间重排(至少发生了39次易位)和染色体内的重排导致了二者核型的差异。根据杂交结果绘制了首份人和白眉长臂猿比较染色体图谱,并结合已有的人和白掌长臂猿(Hylobates lar)(2n=44)和合趾长臂猿(Hylobates syndactylus)(2n=50)的比较染色体图谱对长臂猿属的染色体进化作了初步的探讨。     

Asymmetric somatic hybridization between Triticum aestivum L. and Haynaldia villosa Schur

Suspension cell-derived protoplasts of wheat, inactivated with different concentrations (0-2.5mol/L) of IOA, were fused by PEG method with the Haynaldia villosa protoplasts which originated from the calli 4-5d after subculture and were irradiated with 60Co-γ ray. Cell colonies, calli or regenerated plants were obtained from different combinations of fusion. The calli and plants were verified to be hybrids by chromosome counting, isozyme analysis and morphological inspection.     

Cytogenetic Studies on the Cross generations Between Triticum aestivum and Eremopyrum orientale

The cytogenetics of the backcross generations and self-bred progenies (BC2F1, BC3F1, BC2F2, BC3F2 and BC2F3) of intergenetic hybrid of Triticum aestivum L. x Eremopyrum orientale (kedeb) Jaub. Et Spach were studied. The results showed that the plants BC3F1 (2n = 43 ) isolated from the backcross generations of the plants (2n = 44 ) accounted for 41.09%, but the plants (2n = 44) isolated was only 4. 11%, and the plants BC2F2 (2n = 44) isolated from self-cross generations of the plants BC2F1 (2n = 44) accounted for 13.21%. The number of univalents in pollen mother cells was higher in some plants (BC2F1) and the averages of univalents were negatively related to the backcross seed-setting and self-cross seed-setting with a related coefficient of － 0.6766* and －0.7429* respectively. The results of genomic in situ hybridization (GISH) showed that some plants of BC2Fs (2n=44) contained different number of alien chromosomes. All those indicated that alien chromosomes caused unusual pairing and segregation of wheat homologous chromosomes and also lowed the hereditary stability of wheat chromosomes.     

Comparative study of symmetric and asymmetric somatic hybridization between common wheat and Haynaldia villosa

Symmetric and asymmetric protoplast fusion between long term cell suspension-derived protoplasts of Triticum aestivum (cv. Jinan 177) and protoplasts of Haynaldia villosa prepared from one-year-old embryogeneric calli was performed by PEG method. In asymmetric fusion, donor calli were treated with gamma ray at a dose of 40, 60, 80 Gy (1.3 Gy/min) respectively and then used to isolate protoplasts. Results of morphological, cytological, biochemical (isozyme) and 5S rDNA spacer sequence analysis revealed that we obtained somatic hybrid lines at high frequency from both symmetric and asymmetric fusion. Hybrid plants were recovered from symmetric and low dose γ-fusion combinations. GISH (genomic in situ hybridization) analysis proved exactly the existence of both parental chromosomes and the common occurrence of several kinds of translocation between them in the hybrid clones regenerated from symmetric and asymmetric fusion. And the elimination of donor DNA in hybrid clones regenerated from asymmetric fusion     

宁夏固原地区农村回、汉族近亲结婚的调查

固原地区位于宁夏南部山区,共辖６县,总人口１６２．２万,其中回族占４６．２％。当地经济、文化等条件都非常落后,加之风俗习惯的影响,致使本地近亲婚配多见,尤其回族较多,出生遗传缺陷也较多。在加拿大基金会的援助下,我所于１９９２年８月对本地区农村的回、汉...     

莲C_0t-1 DNA的荧光原位杂交分析

为分析中国莲C_0t-1 DNA在其中期染色体上的分布,从中国莲基因组DNA中分离出C_0t-1 DNA,将基因组和所分离的C_0t-1 DNA用生物素标记后作探针,对中国莲染色体进行原位杂交。杂交结果用耦联有荧光素Cy3的生物素抗体检测,发现在每对染色体上均显示出特定的荧光原位杂交带。同时分析了FISH和GISH信号分布的异同。基于C_0t-1 DNA荧光原位杂交带型及染色体型,构建了中国莲核型。