+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Effects of divalent-cation chelators and chloramphenicol on the spatial relationship of the nuclear envelope to chromatin in micronuclei of Chinese hamster cells

Effects of divalent-cation chelators and chloramphenicol on the spatial relationship of the nuclear envelope to chromatin in micronuclei of Chinese hamster cells

Journal of Supramolecular Structure 9(4): 459-471

In the presence of the spindle poison Colcemid in the culture medium to prevent anaphase, approximately 20% of Chinese hamster metaphase cell were converted to micronucleated cells during 7 h. In the micronuclei the chromosome had become enclosed by a nuclear envelope (NE). In the light-microscope the micronuclei were of two kinds: with either visible chromatids or with decondensed chromosomes. In the electron microscope (EM) the spatial relationship of the NE to the chromatin was of two kinds only in the presence of Colcemid. In about 90% of the micronucleated cells the spatial relationship was normal, ie, the NE was immediately adjacent to the chromatin. In the remaining cells, the NE was distended so that the outer NE was separated from the inner one. In the presence of the divalent cation chelator, (ethylenedinitrilo) tetraacetic acid (EDTA) or the Ca2+-chelator [ethylenebis (oxyethylenenitrilo)] tetraacetic acid (EGTA) in addition to Colcemid, the amount of cells with micronuclei increased to 40%. The light-microscope appearance was the same as that found in the absence of the chelating agents. However, after Colcemid plus EGTA, EM revealed that only about 50% of the micronucleated cells had NE that was immediately adjacent to the chromatin and about 10% of them had distended outer NE. In the remaining 40% a third kind of spatial relationship was seen: the NE was intact but most of it was not adjacent to the chromatin. Furthermore, this type of micronucleus often contained mitochondria within the confines of NE. Thus, Ca2+ and possibly Mg2+ may regulate the rate of formation of the NE and also its ultrastructural relation to the chromatin. Mitochondrial function also appears to be involved in this relationship. In the presence of chloramphenicol (CAP), an inhibitor of mitochondrial protein synthesis, in addition to Colcemid, only about 50% of the micronucleated cells exhibited the normal relationship. The outer NE was separated from the inner NE in about 46% of the micronucleated cells and the third kind of NE-chromatin relationship was observed only in 2%. In the case of the third kind of relationship produced by CAP, inclusion of mitochondria within the micronuclei was not observed, in contrast to the finding with EGTA.

Please choose payment method:

(PDF emailed within 0-6 h: $19.90)

Accession: 038935150

Download citation: RISBibTeXText

PMID: 108479

DOI: 10.1002/jss.400090402

Related references

Alterations produced by chelators of divalent cations and chloramphenicol in the association of the nuclear envelope with chromatin. Journal Of Cell Biologypart 2: 5a, 1977

Effect of divalent cations and chelators on metaphase to telophase progression and nuclear envelope formation in Chinese hamster cells. Cell Calcium 4(4): 237-252, 1983

Regulation of nuclear envelope formation in chinese hamster cells by chelating agents and chloramphenicol. Federation Proceedings: 252, 1976

Ultrastructural changes in the nuclear envelope during mitosis of Chinese hamster cells: a proposed mechanism of nuclear envelope reformation. Journal of the National Cancer Institute 53(4): 1033-1048, 1974

Nuclear envelope of Chinese hamster ovary cells. Re-formation of the nuclear envelope following mitosis. Biochemistry 19(2): 277-289, 1980

Effects of ultracentrifugation on the interphase nucleus of somatic cells with special reference to the nuclear envelope-chromatin relationship. Zeitschrift für Zellforschung und Mikroskopische Anatomie 108(3): 297-308, 1970

Capacitation of hamster spermatozoa with the divalent cation chelators D-penicillamine, L-histidine, and L-cysteine in a protein-free culture medium. Gamete Research 23(2): 159-170, 1989

Chemical capacitation of hamster spermatozoa in a protein free medium with divalent cation chelators and the subsequent requirement for albumin for zona pellucida penetration. Biology Of Reproductionppl. 1: 59, 1988

Nuclear envelope dna interaction in x irradiated cho chinese hamster ovary cells. Radiation Research 70(3): 640, 1977

Micronuclei, CREST-positive micronuclei and cell inactivation induced in Chinese hamster cells by radiation with different quality. International Journal of Radiation Biology 76(3): 367-374, March, 2000

The relationship between colony-forming ability, chromosome aberrations and incidence of micronuclei in V79 Chinese hamster cells exposed to microwave radiation. Mutation Research 263(3): 143-149, 1991

Effects of divalent cations, lanthanum, cation chelators and an ionophore on acetylcholine antinociception. Journal of Pharmacology and Experimental Therapeutics 205(2): 311-318, 1978

Effects of divalent cations, cation chelators and an ionophore on morphine analgesia and tolerance. Journal of Pharmacology and Experimental Therapeutics 195(3): 488-498, 1975

Platelet aggregation and secretion effects of anti coagulants and divalent cation chelators. Thrombosis & Haemostasis: 123, 1977

Phosphoinositide metabolism in human blood platelets: effects of two types of divalent cation chelators. Thrombosis Research 26(4): 241-247, 1982