经甫树蛙的染色体组型、C带和Ag-NORs的研究

本文分别用骨髓细胞染色体标本制作法、BSG技术和一种快速、简便的Ag-NORs显带技术,首次研究了经甫树蛙的染色体组型、C带和Ag-NORs。结果表明,经甫树蛙2n=26,有5对大型和8对小型染色体,次缢痕在No.11染色体长臂末端,为C带负染;银染表明,此次缢痕处即是经甫树蛙的“标准NORs”经甫树娃的C带结构异染色质主要是着丝点型和插入型的。文章初步讨论了树蛙属的细胞分类、经甫树蛙次缢痕、Ag-NORs和C带的关系。     

十一种无尾两栖类分带核型的比较研究

本文比较研究11种无尾两栖类的c带型和人Ag-NORs,并报道三种核型（淡肩角蟾,秦岭雨蛙和湖北金线蛙）,结果：（1） 弹琴蛙仅大型染色体着丝点区C带正染,其余10个物种的所有染色体均有明显的着丝点C带,并分别具有数目不等的端部C带或插入型C带。其中天台蛙的C带尤为发达。（2） 中华大蟾蛛有3对Ag-NORs,大树蛙两对,其余9个种均显示1对。（3）新报三种核型中,淡肩角蟾租湖北金线蛙2n=26,N．F=52。淡肩角蟾由6对大型的和7对小型的染色休组成,湖北金线蛙大小型染色体分别为5对和8对。秦岭雨蛙2n=24,含大小型染色休各6对,其N．F=48。三个物种均未见有异型性染色体。     

黄颡鱼染色体的C-带、Ag-NORs、荧光带和复制带显带的研究

采用Giemas染色、C-带、Ag-NORs、荧光染色和复制带显带的技术对黄颡鱼染色体进行了研究。结果表明, 黄颡鱼只有部分的染色体呈现阳性C-带, 可分为三类, 其中NORs区是染色最深、染色面积最大的区域, 为深染居间C-带。其Ag-NORs位于m5q末端。CMA3染色显示 NORs区呈现出明亮的荧光。中复制染色体上着丝粒区、端粒区和居间区浅染。发现核仁缢痕、深染居间C-带、Ag-NORs、CMA3明亮区和中复制带浅染NORs区位置基本一致, C-带阳性区和中复制带浅染区具有对应性。 Abstract　Metaphase chromosomes of Pelteobagrus fulvidraco were analyzed by means of Giemsa staining, C-banding, Ag-NORs, fluorochrome staining and replication banding. Only parts of chromosomes showed C-band positive, the C-band heterochromatin was located in three regions. The NORs-bearing chromosomes had the largest and strongest C-bands. The long arms of chromosome pair 5 were the regions showing positive labeling with Ag-staining. Fluorochrome CMA3positively stained the NORs. In mid-period, negative replication bands were located in the centromere, the terminal and interstitial regions of the chromosomes. The distributions of secondary ?constri-ctions, positive C-bands, Ag-NORs, positive fluorescence bands and negative replication bands of mid-period were coincident.     

黄颡鱼染色体的C-带、Ag-NORs、荧光带和复制带显带的研究

采用Giemas染色、C-带、Ag-NORs、荧光染色和复制带显带的技术对黄颡鱼染色体进行了研究。结果表明, 黄颡鱼只有部分的染色体呈现阳性C-带, 可分为三类, 其中NORs区是染色最深、染色面积最大的区域, 为深染居间C-带。其Ag-NORs位于m     

云南三种角蟾的细胞遗传学研究

本文研究了云南三种角蟾的核型,C－带和Ag-NORs,结果显示宽头大角蟾,其2n=26(16M 8SM 2T),NF=50,5 8,No.10为T,次缢痕和Ag－NORs位于1p per,该区域同时还呈现C－带正染,其全部染色体的着丝点都有强弱不等的C－带染色;大花角蟾的核型2n=26(16M 8SM=2ST),NF＝50,5＋8,No.6为ST,次缢痕和Ag-NORs位于5q pes,全部着丝点均有C－带正染;凹顶角蟾5n=26(16M 4SM 6T),NF=46,6 7.No.11-13为T,次缢痕和Ag-NORs位于5q per,全部着丝点及周围均有浓C－带正染。三个种均未发现与性别相关的异形染色体,最后讨论了角蟾属核型演化的途径。     

河南花背蟾蜍的核型、C-带和Ag-NORs研究

利用骨髓细胞蒸汽固定法制备染色体标本,研究了分布于河南新乡的花背蟾蜍(Bufo raddei)的核型、C-带和Ag-NORs。结果表明：河南产花背蟾蜍体细胞染色体数为22条,核型公式为2n=22(20m 2sm),全部为中部或亚中部着丝点染色体,NF=44。Ag-NORs具有多态现象。C-带核型显示22条染色体的着丝点均正染,No．1染色体近着丝粒处有不恒定插入型C-带,No．4染色体具有恒定近端部插入型C-带,随体部位被正染的仅占所观察细胞的15％。     

四种无尾两栖类染色体组型的比较研究

本文报道了四种无尾两栖类——Rana pleuraden Boulenger,R.cates-beiana(Shaw),R.japonica chaochiaoensis Liu和Hyla annectans (Jerdon)的染色体组型。采用秋水仙素—低渗—空气干燥法制作染色体标本。用骨髓及肠管作实验材料。蛙属(Rana)的三个种,2n=26,由5对大型染色体、8对小型染色体组成,都是中部或亚中部着丝点染色体,而无端部或亚端部着丝点染色体。他们共有一对亚中部着丝点染色体,即第三对染色体。以上两点表明其染色体演化上的同源性。但是,三者之间亦有明显的差异。滇蛙的次缢痕仅出现在第十对染色体的长臂上,而牛蛙,除此之外,在第七、八两对染色体的短臂上有之;而昭觉林蛙则有三个以上的次缢痕,而且长臂次缢痕不在第十对,而在第七、第八对染色体上,且有三对随体,第十对染色体的次缢痕是在短臂上。 华西雨蛙的2n=24,亦可分成二群:5对大型染色体为一群,7对小型染色体为另一群,次缢痕出现在第九对染色体的长臂上。     

云南三种齿蟾的细胞遗传学研究(锄足蟾科Pelobatidae,无尾目Anura)

本文报道了分布在云南的3种齿蟾(乡城齿蟾、景东齿蟾和棘疣齿蟾)的核型、Ag-NORs和C-带,结果表明2n=26(6+7).NF=52,一对次缢痕和Ag-NORs位于6 q,该区域同时被C-带正染,其余C-带位于各对染色体的着丝点区域。这些特征表现出3种齿蟾的核型同源性和原始性。齿蟾属内种间各对应染色体对在相对长度和臂比值的差异显著性测定表明其核型演化途径可能是臂间倒位和相互易位。3种齿蟾具有染色体数目和Ag-NORs的变异和异形现象,其中乡城齿蟾的一个多余染色体呈现C-带正染,因此可能是B染色体,是锄足蟾科中首次报道。三种齿蟾均未发现与性别相关的异形染色体。     

哀牢蟾蜍和新疆绿蟾蜍的核型、C-带和Ag-NORs

本文报道了云南的哀牢蟾蜍和新疆绿蟾蜍的核型、C-带和Ag-NORs。新疆绿蟾蜍2n=44(36M+8SM),NF=88,除Nos.7,8,13,14四对是SM外,其余诸对均为M,一对随体和Ag-NORs位于12q ter,C-带位于全部染色体的着丝点区域,随体位置也显示C-带,并有少数不稳定的端位和插入型C-带。推测它可能是来自欧洲绿蟾蜍的老四倍体类型。哀牢蟾蜍2n=22(20M+2SM),NF=44,其中只有No.7为SM,一对Ag-NORs和随体位于6q ter,但该区域不着染C-带;全部染色体的着丝点显示不同程度的C-带正染;本种未发现与性别相关的异形染色体。最后,文中讨论了蟾蜍属的核型演化机制。     

湖蛙的染色体组性和Ag-NORs研究

我们采用改进的空气干燥法和Ag-NORs显带技术,分析了分布于新疆的湖蛙(Rana ridibunda pallas)的染色体组型、减数分裂及Ag-NOR。结果表明,湖蛙体细胞的二倍体染色体数目2n=26,由5对大型的染色体和8对小型的染色体组成。雌、雄个体间为发现异型性染色体的存在。Ag-NORs定位于第10对染色体长臂上的次缢痕处。在本次工作中,我们还发现,湖蛙除在伊犁外,博乐、乌鲁木齐市郊也有分布。     

Comparative chromosomal studies on two minnow fish, Phoxinus phoxinus (Linnaeus, 1758) and Eupallasella perenurus (Pallas, 1814); an associated cytogenetic-taxonomic considerations

The present work provides new data on the banding pattern of two cyprinid fish species Phoxinus phoxinus and Eupallasella perenurus from Poland. C-banding, silver-staining (Ag), and fluorescent staining with chromomycin A₃ techniques were used to describe the karyotypes. Both of the species karyotypes of 2n=50 were characterised by one pair of acrocentric chromosomes, the largest in the set, and by two pairs of NOR-bearing chromosomes. In the chromosome set of Ph. phoxinus Ag-stained NORs were located on telomeres of two metacentric and two submetacentric chromosomes, but in most metaphases only one of the two homologous was observed. The karyotype of E. perenurus was characterised by Ag-NOR regions at a telomeric position on the shorter arm of two submetacentric chromosome pairs. In most metaphases only three NOR-bearing chromosomes were observed. In both investigated species the location of the A₃ positive signals corresponded with the location of Ag-stained NORs and these sites were associated with heterochromatin shown as C-bands. The results of cytogenetical studies on other related, mainly the North American phoxinins, species are compared and discussed.     

小熊猫染色体异染色质的显示

以培养的小熊猫外周淋巴细胞为实验材料,结合Ｃ－显带技术及ＣＭＡ３／ＤＡ／ＤＡＰＩ三竽荧光杂色的方法,对小熊猫的染色体组型、Ｃ－带带型及ＣＭＡ３／ＤＡ／ＤＡＰＩ荧光带带型进行了研究,发现：（１）经Ｃ－显带技术处理,可在小熊猫染色体上呈现出一种极为独特的Ｃ－带带型。在多数染色体上可见到丰富的插入Ｃ－带及端粒Ｃ－带。而着丝区仅显示弱阳性Ｃ－带;（２）除着丝粒区外,ＣＭＡ３诱导的大多数强荧光带纹与Ｃ－阳性     

石貂的染色体研究

本文对分布在我国的石貂北方亚种染色体进行了较详细的研究。结果表明２ｎ＝３８,核型为１４（Ｍ）＋４（ＳＭ）＋１８（ＳＴ）,ＸＹ（Ｍ,Ａ）。Ｃ－带显示该亚种的一些染色体着丝粒区域结构异染色质弱化或消失。Ｎｏ,９染色体的短臂完全异染色质化;Ｘ染色体长臂丰出现插入杂色质带;Ｙ为完全结构异染色质组成。     

The chromosome banding pattern in two cytotypes (2n = 36 and 38) of blind mole rats from Turkey (Mammalia: Spalaxidae)

Two cytotypes (2n = 36 and 38) of blind mole rats, Nannospalax xanthodon (Nordmann, 1840), from the Ayd?n and Manisa provinces in Turkey were investigated. Conventional chromosome staining, Ag-NOR staining and C-banding analysis were carried out. From the cytogenetic point of view, the particular phylogenetic position of these populations is supported by their low diploid numbers only, and the Cbanding pattern and the NORs distribution seem generally similar to populations with higher chromosome numbers. Several autosomal pairs with centromeric dark Cbands were observed in the 2n=36 cytotype. One autosomal pair possessed an interstitial dark C-band on the short arm; another pair possessed an interstitial dark Cband on the long arm. Whole C-heterochromatic short arms were observed in three subtelocentric autosomal pairs in the 2n=38 cytotype. Most of the other autosomal pairs possessed centromeric dark C-bands. Distinct dark C-bands were observed also in the presumed X chromosomes of both the cytotypes. The Ag-NOR regions were found on three autosomal pairs of both the cytotypes. These sites were located in telomeric areas of the short arms of two subtelocentric and one submetacentric pair.     

黄颡鱼染色体的C─带、Ag—NORs、荧光带和复制带显带的研究

采用Giemas染色、C─带、Ag—NORs、荧光染色和复制带显带的技术对黄颡鱼染色体进行了研究。结果表明,黄颡鱼只有部分的染色体呈现阳性C─带,可分为三类,其中NORs区是染色最深、染色面积最大的区域,为深染居间C─带。其Ag－NORs位于m5q末端。CMA3染色显示NORs区呈现出明亮的荧光。中复制染色体上着丝粒区、端粒区和居间区浅染。发现核仁缢痕、深染居间C─带、Ag—NORs、CMA3明亮区和中复制带浅染NORs区位置基本一致,C─带阳性区和中复制带浅染区具有对应性。     

Cytogenetic characterization of the bay scallop, Argopecten irradians irradians, by multiple staining techniques and fluorescence in situ hybridization

The chromosomes of Argopecten irradians irradians were studied by various cytogenetic approaches. Conventional chromosome characterization built on C-banding, DAPI-staining, and silver staining was complemented by the physical mapping of ribosomal DNA and telomeric sequence (TTAGGG)n by FISH. Results showed that the constitutive heterochromatin revealed by C-banding was mainly distributed at telomeric and centromeric regions. However, interstitial C-bands were also observed. The pattern of DAPI banding was almost consistent with that of C-banding. Silver staining revealed that NORs were located on the short arms of chromosome 3 and 10, and this was further confirmed by FISH using 18S-28S rDNA. 5S rDNA was mapped as two distinguishable loci on the long arm of chromosome 11. 18S-28S and 5S rDNA were located on different chromosomes by sequential FISH. FISH also showed that the vertebrate telomeric sequence (TTAGGG)n was located on both ends of each chromosome and no interstitial signals were detected. Sequential 18S-28S rDNA and (TTAGGG)n FISH demonstrated that repeated units of the two multicopy families were closely associated on the same chromosome pair.     

水貂的染色体研究

采用复制带、C带和硝酸银染色等分带技术研究了水貂的核型和带型。结果表明,2n=30,枝型为10（M）＋16（SM）＋2（A）,XX（M）。C-带显示该水貂的一些染色体的结构异染色质比较丰富,从着丝粒区域延伸到两臂上,No.5染色体着丝粒结构异染色质有些弱化;X染色体的结构异染色质较常染色体的丰富。Ag-NORs有3个,分布在No.8染色体的次缢痕区域和一条No.2染色体长臂接近着丝粒的区域。     

The mitotic chromosomes of Notophthalmus (=Triturus) viridescens: Localization of C banding regions and DNA sequences complementary to 18S, 28S and 5S ribosomal RNA

The metaphase chromosomes of Notophthalmus (Triturus) viridescens have been studied by C-banding and in situ hybridization. The chromosomes show the pericentric C-banding seen in many organisms and in addition have interstitial C-bands located a short distance from the pericentric C-bands on each chromosome arm. A few C-bands are seen in telomeric regions. Regions which hybridize in situ with 18S and 28S ribosomal RNA were found on three chromosome pairs. The animals studied fell into three groups with respect to which of the six possible sites showed detectable hybridization with 18S and 28S RNA. Individual animals differed not only in the pattern of in situ hybridization of ribosomal RNA but also in the number of ribosomal RNA cistrons in the genome as measured by saturation hybridization on purified DNA. In situ hybridization showed five pairs of chromosomes which contained DNA complementary to 5S RNA. The four pairs of subtelocentric chromosomes in the N. viridescens karyotype all have 5S DNA in the pericentric regions. The fifth cluster of 5S DNA is in the middle of one arm of the chromosomes in one of the two smallest submetacentric pairs in the genome. The five sites of 5S DNA differ markedly in the level of in situ hybridization with 5S cRNA.