Abstract
Mammalian chromosome replication was studied by the aid of premature chromosome condensation (PCC). After induction of PCC the sites of DNA replication appear as “gaps” between condensed chromosomal regions. These condensed particles are unineme before and bineme after DNA replication. The two phases are due mainly to the unineme or bineme nature of the particles. During early S-phase almost all particles are unineme, during late S-phase they are bineme and there is only one transitory stage between these two main stages. Premature chromosome condensation was studied in detail on a specific human chromosome 22 which is marked by its heterochromatin constitution. This led to easy identification of these elements in S-phase PCC (S-PCC) preparations. For each stage of the S-phase there was a reproducible pattern of condensed chromosomal particles making up the whole chromosome. The number of these particles was rather limited and a complementary pattern was found in early versus late S-phase. The pattern of early S-PCC corresponded to the banding pattern of G-banded prometaphase chromosomes; the pattern of late S-PCC, to R-banded prometaphase chromosomes. Thus, “gaps” and condensed particles as observed after PCC induction are obviously homologous to chromosome replication units. Replication of constitutive heterochromatin occurred during the very late S-phase. During this stage PCC induction led to condensation of the heterochromatin into several small, highly fluorescent particles.
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References
Calderon D, Schnedl WA (1973) A comparison between quinacrine fluorescence banding and 3H-thymidine incorporation. Hum Genet 18:63–70
Camargo M, Cervenka J (1982) Patterns of DNA replication of human chromosomes. II. Replication map and replication model. Am J Hum Genet 34:757–780
Dutrillaux B, Couturier J, Richter C-L, Viegas-Pequignot E (1976) Sequence of DNA replication in 277 R- and Q-bands of human chromosomes using BrdU treatment. Chromosoma 58:51–61
Ganner E, Evans HJ (1971) The relationship between pattern of DNA replication and of quinacrine fluorescence in the human chromosome complement. Chromosoma 35:326–341
Grzeschik K-H, Kim MA, Johannsmann R (1975) Late replicating bands of human chromosomes demonstrated by fluorochrome and Giemsa staining. Humangenetik 29:41–59
Hand R (1978) Eucaryotic DNA: Organization of the genome for replication. Cell 15:317–325
Holmquist G, Gray M, Porter TJ, Jordan J (1982) Characterization of Giemsa dark- and light-band DNA. Cell 31:121–129
ISCN (1978) An international system for human cytogenetic nomenclature (1978). Birth defects: Original Article Series, Vol. XIV, No. 8 (The National Foundation, New York 1978); also in Cytogenet. Cell Genet 21:309–404
Kim MA, Johannsmann R, Grzeschik K-H (1975) Giemsa staining of the sites replicating DNA early in human lymphocyte chromosomes. Cytogenet Cell Genet 15:363–371
Latt S (1975) Fluorescence analysis of late DNA replication in human metaphase chromosomes. Somatic cell Genet 1:293–321
Lau Y-F, Arrighi FE (1981) Studies of mammalian chromosome replication. II. Evidence for the existence of defined chromosome replication units. Chromosoma 83:721–741
Meer B, Hameister H, Cerillo M (1981) Early and late replication patterns of increased resolution in human lymphocyte chromosomes. Chromosoma 82:315–319
Röhme D (1975) Evidence suggesting chromosome continuity during the S-phase of Indian muntjac cells. Hereditas 80:145–149
Schempp W (1980) Asynchrony in late replication between homologous autosomes in primary cultures of Chinese hamster fibroblasts. Chromosoma 79:199–206
Schempp W, Vogel W (1978) Decrease of DNA synthesis in amniotic fluid cells during the middle part of S-phase revealed by differential chromosome staining after incorporation of BrdU. Chromosoma 67:193–199
Schmidt M (1980) Two phases of DNA replication in human cells. Chromosoma 76:101–110
Schnedl W, Abraham R, Dann O, Geber G, Schweizer D (1981) Preferential fluorescence staining of heterochromatic regions in human chromosomes 9, 15 and the Y by D287/170. Hum Genet 59:10–13
Sperling K (1982) Cell cycle and chromosome cycle: morphological and functional aspects. In: Rao PN, Johnson RT, Sperling K (eds), Premature chromosome condensation. 43–78. Academic Press New York
Sperling K, Rao PN (1974) Mammalian cell fusion. V. Replication behavior of heterochromatin as observed by premature chromosome condensation. Chromosoma 45:121–131
Taylor JH (1960) Asynchronous duplication of chromosomes in cultured cells of Chinese hamster. J Biophys Biochem Cytol 7:455–463
Willard HF (1977) Tissue-specific heterogeneity of DNA replication patterns of human X chromosomes. Chromosoma 61:61–73
Yunis JJ (1981) Mid-prophase human chromosomes. The attainment of 2000 bands. Hum Genet 56:293–298
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Dedicated to Prof. Marlies Tolksdorf on the occasion of her 60th birthday
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Hameister, H., Sperling, K. Description of a chromosome replication unit in individual prematurely condensed human S-phase chromosomes. Chromosoma 90, 389–393 (1984). https://doi.org/10.1007/BF00294166
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DOI: https://doi.org/10.1007/BF00294166