A Technique for C-banding Chromosomes with Pinacyanol Chloride

A technique is presented for rapid C-banding of eukaryotic chromosomes with pinacyanol chloride. This technique has given excellent definition and clarity to chromosome bands in plant and animal chromosomes. In permanent mounts the chromosomes did not fade after storage for up to two years.     

A Modified Giemsa C-Banding Technique For Hordeum Species

A Giemsa C-banding technique with a hot 1 N HCI hydrolysis step has been developed for barley chromosomes. This step makes it easy to obtain well separated C-banded chromosomes. To compare this technique with other C-banding techniques, chromosomes of H. vulgare cv. York were stained by both this technique and a modification of the technique of Kimber et al (1976). With respect to centromeric and intercalary bands, both techniques produce a similar banding pattern, but telomeric bands observed by the modified technique of Kimber et al (1976) were not detected by our procedure. This indicates that telomeric heterochromatin may be different chemically and/or structurally from the centromeric and intercalary heterochromatin and its appearance dependent upon the C-banding technique. The procedure described provides a relatively rapid technique for C-banding of barley chromosomes.     

On the Quinacrine fluorescence and Giemsa staining patterns of the chromosomes of Vicia faba

Abstract

A comparison has been made between the Quinacrine fluorescence bands and the bands obtained with a denaturating-reannealing-Giemsa technique in Vicia faba. The results show that some of the bands, particularly on the M and, proximally, on the S chromosomes are visible with both techniques. A complex pattern of bands on the S chromosomes is revealed with the Giemsa technique. Both the similarities and the differences between the banding patterns obtained with the two methods in Vicia faba may indicate various degrees of DNA repetitiousness and other physico-chemical properties in the chromosome segments involved.     

BrdU处理的鱼类染色体高分辨G-带带型分析

本文应用鱼类染色体高分辨G-带技术,重点将黄鳝培养细胞具不同长度染色体的正中期分裂相做成G-带核型加以比较分析。随着染色体长度的增加,带纹数目也增加。但增加是有限度的。染色体带纹数目的增加,明显地表现在深染带再分为若干亚带。当染色体从前期向中、后期过渡收缩变短时,一些亚带融合为原来数目的带。染色体上各个带的收缩程度、收缩时间是不均等的。实验证明大剂量的BrdU不仅能阻断鱼类细胞于中S期,也可使染色体伸长、小剂量的伸长作用不明显。最后讨论了BrdU处理与G-显带的关系、染色体带纹数目相对恒定以及染色体伸长缩短问题。     

Giemsa banding of meiotic chromosomes

Applying a Giemsa staining technique to the meiotic chromosomes of Anemone blanda demonstrates that Giemsa bands similar to those seen in the mitotic chromosomes are discernible at all the principal stages of meiosis. The bands are not a product of the Giemsa procedure since they can be seen in unstained preparations using phase-contrast optics as chromocentres in interphase nuclei and as condensed regions in prophase chromosomes. That the bands seem to be permanent features of the nucleus, whether it is dividing or otherwise is an important consideration for understanding their nature and function. Bands and chiasmata do not coincide indicating on the one hand that chiasmata are not responsible for differences in banding patterns and on the other hand that the conservation of bands is an indication that they are either inert regions or specialised regions with considerable adaptive significance. These alternatives can only be resolved by genetical studies of the banding phenomena.     

蚕豆染色体的复制带显带技术

本文采用作者首创的双周期BrdU二次标记法研究了蚕豆根尖细胞染色体的复制带,得到了分布在整条染色体上的清晰稳定的多条带纹.这是复制带首次在植物染色体上取得的具有实用意义的带型.为进一步制定植物染色体的标准带型和研究植物染色体的复制方式提供了一条途径.     

Location of repetitious DNA in the chromosomes of the desert locust (Schistocerca gregaria)

A modified Giemsa staining technique and the in situ hybridisation technique, have been used to investigate the localisation of highly repeated sequences in the karyotype of the locust Schistocerca gregaria. The centromeric regions are stained densely with Giemsa and further Giemsa-stained bands occur at the telomeric region of the short (S) chromosomes. RNA complementary to repetitious DNA hybridised to loci scattered along the whole length of the chromosomes, with concentrations of grains at the centromeric regions of all the chromosomes and also at the telomeric regions of the S chromosomes.     

中国家猪高分辨G—带及模式图

采用氨甲喋呤或胸苷阻断法使细胞分裂同步化,并结合胰酶G-带技术,对中国7个家猪品种高分辨G-带进行了研究,发现家猪品种间带型基本一致,从而参照人类细胞遗传学命名法的国际体制,提出了中国家猪高分辨G-带标准化核型及模式图,对显带核型界标进行了少许修改,对每对染色体进行了区带划分和描述。单倍染色体组所显示的G-带数目,包括X和Y染色体,巳达444条,近于中期染色体带纹数目的两倍。     

Constitutive heterochromatin DNA polymorphisms in diploid Medicago sativa ssp. falcata.

A Giemsa C-banding technique was used to study the amount and location of constitutive heterochromatin in diploid (2n = 2x = 16) Medicago sativa ssp. falcata (L.) Arcangeli. Most accessions had the standard C-banding pattern with centromeric bands on all the chromosomes and a prominent heterochromatic band at the nucleolar organizer regions (NOR) of the satellited (SAT) chromosomes. However, we observed in various accessions that constitutive heterochromatic C-bands can exist at the telomeric ends of all the chromosomes. Interstitial bands occurred on the short arms of all chromosomes except for chromosome 3 and on the long arms of chromosomes 1, 2, 3, and 6, only. Rearranged chromosomes such as isochromosomes have been observed for the short arms of chromosomes 2 and 6. This is the first report on the existence of C-banding polymorphisms and the detection of putative isochromsomes in the chromosomes of diploid ssp. falcata which could have contributed to the variation observed in cultivated alfalfa.     

An approach to the G-Banding Technique in Rye Chromosome

The G-banding technique has not yet been broken through in studying plant chromosomes. in this paper, we have described a new banding method in Secale cereale. The rye root tips were treated with actinomycin D (40-100 μg/ml) for two hours and with colchicine (0.01%) for 0.5 hour and then fixed with methanol-acetic acid (3:1). After cell wall degradation by cellulase and pectinase, the chromosome sample were made by a hypotonic and flame-drying method (hypotonic treatment→preparation of cell suspension→dropping suspension on slide flame-drying). Following an air-drying period of about a week, the slides were incubated in trypsin-EDTA solution (0.01–0.05%) at 30℃ for 10–15 sec. and subsequently stained with Giemsa. Lots of deep stained bands along the arms of many prophase and late prophase chromosomes were seen. The position of them was obviously different from that of the C-band and the number of them was approximately in proportion to the longitude of chromosomes. Such bands were not seen in metaphase chromosomes. We thought it preferable to use prophase chromosomes to probe G-banding technique in plant and this paper has proposed a possible way for studying G-banding technique in plant chromosome. We also discuss why metaphase chromosomes of plant do not show G-bands.     

High-resolution cytogenetic characterization of the L5178Y TK+/- mouse lymphoma cell line

High-resolution chromosome preparations from L5178Y TK+/- 3.7.2C mouse lymphoma cells were obtained using acridine orange in the cell harvest procedure. With this technique it is possible to visualize over 500 bands in elongated mouse lymphoma cell chromosomes as compared to the approximately 230 bands visualized in metaphase preparations. High-resolution lymphoma cell chromosomes are described, and chromosome rearrangements carried in the cell line are characterized by ideograms representing the position, number, size, and relative staining intensity of the G-band patterns. Use of elongated chromosomes of mouse lymphoma TK+/- mutants should facilitate analysis of the cytogenetic effects associated with TK+/- ----TK-/- mutagenesis.     

植物染色体G-带的初步研究

本文首次报道了川百台(Lilium davidii)、华山松(Pinus armardii)和七叶一枝花(Paris polyphylla)等植物染色体G-带研究结果。本试验的G-带与以往的C-带不同,C-带每条染色体上一般只有1-4条带,多分布在着丝点附近,而G-带则多达几十条,分布在整条染色体上,带纹清晰,前期染色体带呈颗粒状,中期染色体呈明显的带状,与哺乳动物染色体G-带很相似。G-带的数目取决于染色体浓缩的程度。前期染色体带纹数目是中期的三倍,接近人类高分辨带水平。对G-带带纹采用了自动光谱分析,波峰数值与带纹相符。作者同时介绍了胰酶法在植物染色体G-带中的应用。认为此方法既适合动物亦适用于植物。但植物G-带显示的关键可能不在胰酶法本身,而在合适的分裂时期及染色体处理技术。     

A Technique for C-Banding Plant Chromosomes with Wright Stain

A technique is presented for C-banding plant chromosomes with a modified Wright stain. This procedure consistently produces brightly stained, well defined telomeric and interstitial heterochromatic bands, identifiable centromeric constrictions, and lightly stained euchromatic areas on chromosomes of rye.     

家蚕染色体复制区带的初步显示

该文采用家蚕Bomoyx mori活体注射BrdU结合FPG(fluorochrome photolyusis Giem-sa)显带方法,以生殖腺为材料,成功显示出家蚕有丝分裂中期染色体复制带。由于处于S-期的细胞有早有晚,且同一细胞DNA各片段的复制亦有先后,因此BrdU掺入DNA合成的时间也有所不同,从而可产生出早、中、晚复制带型。BrdU掺入时间早,则会在家蚕部分染色体上出现大面积浅染带纹的早复制带。每一染色体皆有其独特的带纹特征,据此可初步将它与其它染色体相互区分;随着BrdU掺入时间的推后,染色体上会出现深浅交替、丰富的带纹,即中复制带型;至S-期DNA合成晚期掺入BrdU,最终染色体出现以深染带纹为主,浅染带纹仅出现于少数染色体的中部、近中部或端部的晚复制带。     

Replication banding in the chromosomes of the European eel (Anguilla anguilla)

The chromosomes of the European eel Anguilla anguilla have been analyzed with a replication banding technique from lymphocyte cultures treated with 5-BrdU. This technique allows us to identify with high resolution the individual chromosome pairs and to differentiate classes of chromatin by the order of replication. The replication banding obtained on the chromosomes of European eel can be related with the structural bands described in this species.     

A technique for C-banding plant chromosomes with Wright stain

A technique is presented for C-banding plant chromosomes with a modified Wright stain. This procedure consistently produces brightly stained, well defined telomeric and interstitial heterochromatic bands, identifiable centromeric constrictions, and lightly stained euchromatic areas on chromosomes of rye.     

Banding patterns in newt chromosomes by the giemsa stain

Specific banding patterns can be produced on the mitotic chromosomes of the newt species Triturus vulgaris meridionalis and T. italicus by using the Giemsa stain technique. These bands are most useful cytogenetic markers in karyotyping, since they facilitate identification of the individual elements of the complements. Evaluation of the shape of chromosomes as well as of the banding patterns produced by the Giemsa stain indicates that the karyotypes of T. vulgaris meridionalis and T. italicus are differentiated: hence the specific distinction of the two Salamandrids, still debated by taxonomists, appears supported by chromosome evidence. — Most of the bands seem to correspond to the heterochromatic tracts observable on mitotic chromosomes from embryos and larvae either untreated or submitted to cold treatment. Besides, the comparison of mitotic karyotypes and lampbrush maps shows that the bands located near the centromeric regions of mitotic chromosomes probably correspond to the so-called bars visible on either side of centromeres of lampbrush chromosomes, while some of the subterminal bands may correspond to the sphere.This work was financially supported by C. N. R., Roma.     

Centromeric banding (C) of sequentially Q- and R-banded human chromosomes

Summary A modified C-banding technique is described that produces C bands on human chromosomes after sequential Q and R banding and retains good chromosome morphology. Despite the considerable exposure to UV light during sequential Q and R bandings, clear C bands could still be achieved. Employing the present technique, Q, R, and C polymorphisms can be recorded on a single metaphase.     

Mechanisms of chromosome banding : VI. Whole mount electron microscopy of banded metaphase chromosomes and a comparison with pachytene chromosomes

Chinese hamster chromosomes, banded by exposure to actinomycin D during the G 2 period, were examined by whole mount electron microscopy. Bands of condensed chromatin were present in unstained preparations that were not fixed with methanol-acetic acid indicating that the differential condensation of chromatin plays a role in banding by this technique. There was a tendency for interdigitation of the chromatin of the homologous bands on sister chromatids. Since previous studies had shown that the bands of mitotic chromosomes matched the chromomeres of meiotic chromosomes, whole mount electron microscope preparations of pachytene chromosomes were also examined. These suggest that in addition to condensation the chromatin of the chromomeres may also have a higher density of attachment sites to the lateral element of the synaptonemal complex, and probably to the nuclear membrane in interphase cells.