A combination of sister chromatid differential staining and giemsa banding.

We report a procedure for combining sister chromatid differential staining and G banding in the same metaphase plate. Mammalian cells in culture are grown in medium containing 5-bromodeoxyuridine for two cell cycles, and conventional air-dried preparations are made. The slides are treated with a trypsin or a urea solution the same way as for regular G banding. This method is simple and fast and provides additional information for cytogeneticists.     

Sister chromatid differential staining pattern in prematurely condensed chromosomes

Summary Application of sister chromatid differential (SCD) procedure on G₁, S and G₂ prematurely condensed chromosomes (PCC) of cells in the second and third cycle of DNA replication in medium containing BrdU reveals differential staining patterns characteristic of their respective stages in the cell cycle. These findings also suggest a structural similarity between PCC and metaphase chromosomes.Supported in part by grants from the National Foundation-March of Dimes (grant No. 1-327) and from the National Cancer Institute (grant No. CA-16480).     

Contradictory differential staining results with Coomassie Brilliant Blue and silver carbonate on sister chromatids

Summary Coomassie Brilliant Blue, and silver stain, are used in electrophoretic gels to identify polypeptides. The relative staining intensity has been taken as indicating a quantitative difference between proteins. However, when these 2 stains were applied to 2 identically pretreated chromosome preparations, contradictory staining results were obtained.Acknowledgment. This work is supported under the auspices of the National Science Council, Republic of China.     

A differential staining for hypocotyl and radicle

Résumé Dans les études où la distinction entre l'hypocotyle et le radicule est nécessaire, leréactif genevois s'est montré le colorant le plus approprié.     

Visualization of metaphase heterochromatin inVicia faba by the denaturation-renaturation giemsa staining method

Zusammenfassung Die Denaturierungs- und Renaturierungs-Giemsafärbungsmethode auf die Metaphasenchromosomen vonVicia faba angewandt ergab heterochromatische Chromosomensegmente, die sich nach Kältebehandlung oder HCl-Essigsäure Behandlung negativ heterochromatisch verhalten und sich als die stärker Giemsa-gefärbten Segmente erweisen.     

The equilibrium of ubiquitination and deubiquitination at PLK1 regulates sister chromatid separation

PLK1 regulates almost every aspect of mitotic events, including mitotic entry, spindle assembly, chromosome alignment, sister chromatid segregation, metaphase-anaphase transition, cytokinesis, etc. In regulating the chromosome alignment and sister chromatid segregation, PLK1 has to be localized to and removed from kinetochores at the right times, and the underlying mechanism that regulates PLK1 both spatially and temporally only became clearer recently. It has been found that deubiquitination and ubiquitination of PLK1 are responsible for its localization to and dissociation from the kinetochores, respectively. The equilibrium of this ubiquitination and deubiquitination plays an important role in regulating proper chromosome alignment and timely sister chromatid segregation. Here, we summarize and discuss the recent findings in investigating the spatial and temporal regulation of PLK1 during chromosome alignment and sister chromatid segregation.     

Rate of sister chromatid exchanges in mammalian cells differing in diploid numbers

Summary The rate of sister chromatid exchanges (SCE) under identical experimental conditions is the same in various mammalian species irrespective of their diploid chromosome numbers.Supported in part by Research grants VC-21 from American Cancer Society and DEB-76-10580 from National Science Foundation.     

Occurrence of sister chromatid exchanges at euchromatin-C band junctions inAllium cepa chromosomes

Summary Distribution of SCE in C band and non-C band regions ofAllium cepa chromosomes.     

Age-G staining, a rapid technique for producing combined silver staining and Giemsa banding in mammalian chromosomes

A combination of the silver staining method with a Giemsa banding technique is described for mammalian chromosomes. This double staining simultaneously shows silver-stained NORs and a G-band pattern, and thus allows a rapid identification of the NOR-bearing chromosomes.     

Ag-G staining,a rapid technique for producing combined silver staining and Giemsa banding in mammalian chromosomes

Summary A combination of the silver staining method with a Giemsa banding technique is described for mammalian chromosomes. This double staining simultaneously shows silver-stained NORs and a G-band pattern, and thus allows a rapid identification of the NOR-bearing chromosomes.     

A differential staining reaction demonstrating reciprocal activity in mauthner's cells

Zusammenfassung Die Mautnerzellen des Welses (Ameirus) zeigen nach Reizung des N. statoacusticus ein färberisches Verhalten, das erlaubt, sie von ungereizten Zellen mit Sicherheit zu unterscheiden.

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Supported in part by the NIH Grants MY-3271 and H-3084.     

Mitotic response and sister chromatid exchanges in lymphocytes cultured in sera from different sources

Summary The numbers of sister chromatid exchanges in lymphocytes grown in varying concentrations of serum from different sources indicated that some sera contain a factor, probably introduced as a contaminant, which induces SCEs. Sera from 6 animals showed no evidence of a difference in baseline SCE levels due to the donor of the serum.Research sponsored by U.S. Department of Energy contract number DE-ACO5-760R00242 with The University of Tennessee.     

Increases in frequency of sister chromatid exchange following tumor grafts in different immunocompetent hosts]

Measurement of sister chromatid exchanges (SCEs) frequency of inbred Rat or nu/nu Mice bone marrow cells, following tumour grafts, have been developed. Increase of SCEs was observed in hosts which present or not metases and with reduced survival rates after malignant tumour grafts. These results suggest a remote control of tumoral tissue by a diffused matter effect.     

Induction of sister chromatid exchanges in vivo in bone marrow cells of AKR mice]

Induction of sister chromatid exchanges (SCEs) in bone-marrow cells of AKR Mice receiving in vivo four drugs well-known for their mutagenesis activity has been tested. A decreasing activity in SCE was shown by the drugs tested in the order cyclophosphamide, procarbazine, methylmethane sulfonate and diethylnitrosamine. This technique presents an encouraging method for testing the effect of chemical agents in vivo.     

Differential giemsa staining of the holokinetic chromosomes of the two-spotted spider mite,Tetranychus urticae Koch (Acari,Tetranychidae)

Summary The chromosomes of the spider miteTetranychus urticae can be stained differentially with Giemsa-staining methods for G-bands. C-band patterns representing constitutive heterochromatin could not be detected. Their absence may be related to the holokinetic condition of the chromosomes.     

Preimplantation mouse embryos cultured in mouse,rat and human sera: differentiation and sister chromatid exchange

Summary Development of 4-cell and of 8-cell mouse embryos and of morulae and blastocysts is inhibited in vitro by mouse serum but not by rat or human sera which also do not influence sister chromatid exchange in cultured morulae and blastocysts.     

Preimplantation mouse embryos cultured in mouse, rat and human sera: differentiation and sister chromatid exchange

Development of 4-cell and of 8-cell mouse embryos and of morulae and blastocysts is inhibited in vitro by mouse serum but not by rat or human sera which also do not influence sister chromatid exchange in cultured morulae and blastocysts.     

Distribution of sister chromatid exchanges in different types of chromatin in the X chromosome ofMicrotus cabrerae

We used the X chromosomes ofMicrotus cabrerae as a model to analyze the distribution of sister chromatid exchanges (SCEs) on different types of chromatin, because of the marked heterogeneity of the heterochromatin in the entire short arm and a portion of the long arm of this chromosome. Computer-simulated distributions, according to an algorithm that makes it possible to modify the distribution on the basis of any possible hypothesis, were compared with real distributions by log-linear models. We found that the frequency of SCEs in different types of heterochromatin was higher than that expected for a random distribution, and located an SCE hot-spot at the junction between euchromatin and heterochromatin. The possible relationship between the distribution of SCEs and base composition or chromatin accessibility are discussed.