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Differential gene activity and segregation of cell lines: an attempt at a molecular interpretation of the primary events of embryonic development

Published online by Cambridge University Press:  17 March 2009

Mosé Rossi
Affiliation:
C.N.R. Laboratory of Molecular Embryology, 80072 Arco Felice (Napoli), Italy
Gabriella Augusti-Tocco
Affiliation:
C.N.R. Laboratory of Molecular Embryology, 80072 Arco Felice (Napoli), Italy
Alberto Monroy
Affiliation:
C.N.R. Laboratory of Molecular Embryology, 80072 Arco Felice (Napoli), Italy

Extract

The study of differentiation is concerned with the analysis of the processes responsible for ‘the cellular changes in macromolecular synthesis and composition, patterned in time and space and resulting in specialized functions, forms and organization’ (Moscona, 1973).

Type
Research Article
Copyright
Copyright © Cambridge University Press 1975

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References

REFERENCES

Agrell, J. (1956). A mitotic gradient as the cause of the early differentiation in the sea urchin embryo. Zoological Papers in Honour of B. Hanström (ed. Wingstrand, K. G.), pp. 2734.Google Scholar
Allfrey, V. G., Littau, V. C. & Mirsky, A. E. (1963). On the role of histones in regulating ribonucleic acid synthesis in the cell nucleus. Proc. Natn. Acad. Sci. U.S.A. 49, 414–21.Google Scholar
Augusti-Tocco, G. & Monroy, A. (1975). Gene controlled regulatory processes in the development of marine organisms. In Biochemical and Biophysical Perspectives in Marine Biology. London: Academic Press.Google Scholar
Balinsky, B. I. (1966). An Introduction to Embryology. Philadelphia and London: W. B. Saunders Company.Google Scholar
Bellairs, R. (1971). Developmental Processes in Higher Vertebrates. London: Logos Press.Google Scholar
Bernstein, R. M. & Mukherjee, B. B. (1973). Cytoplasmic controlof nuclear activity in preimplantation mouse embryos. Devl Biol. 34, 4765.Google Scholar
Berrill, N. J. (1935). Studies in tunicate development. 3. Differential retardation and acceleration. Phil. Trans. R. Soc. Lond. B 225, 255326.Google Scholar
Bird, A., Rogers, E. & Birnstiel, M. (1973). Is gene amplification RNA directed ? Nature (New Biol.) 242, 226–9.CrossRefGoogle ScholarPubMed
Bischoff, R. & Holtzer, H. (1970). Inhibition of myoblast fusion after one round of DNA synthesis in 5-bromodeoxyuridine. J. Cell Biol. 44, 134–50.Google Scholar
Bishop, J. O. & Pemberton, R. E. (1973). Molecular hybridization between labelled 9S messenger RNA and DNA from the red blood cells of normal and anaemic ducks. FEBS Symp. no. 24. Biochemistry of Cell Differentiation (ed. Monroy, A. and Tsanev, R.), pp. 2539. London, New York: Academic Press.Google Scholar
Bonner, J., Dahmus, M. E., Fambrough, D., Huang, R. C., Marushige, K. & Tuan, D. Y. H. (1968). The biology of isolated chromatin. Science, N.Y. 159, 1756.Google Scholar
Borek, E. & Srinivasan, P. R. (1966). The methylation of nucleic acids. A. Rev. Biochem. 35, 275–98.Google Scholar
Boveri, T. (1899). Die Entwicklung von Ascaris megalocephala mit besonderer Rücksicht auf die Kernverhältnisse. Festschr. F. C. von Kapper, pp. 383430. Jena.Google Scholar
Brachet, J. (1973). Introduction to Molecular Embryology. New York, Heidelberg, Berlin: Springer-Verlag.Google Scholar
Britten, R. J. & Davidson, E. H. (1969). Gene regulation for higher cells: a theory. Science, N. Y. 165, 349–57.Google Scholar
Brown, G. M. & Attardi, G. (1965). Methylation of nucleic acids in HeLa cells. Biochem. biophys. Res. Commun. 20, 298302.Google Scholar
Brown, D. D. & Gurdon, J. B. (1964). Absence of ribosomal RNA synthesis in the anucleolate mutant of Xenopus laevis. Proc. natn. Acad. Sci. U.S.A. 51, 139–46.Google Scholar
Brown, D. D. & Dawid, I. B. (1968). Specific gene amplificationin oocytes. Science, N.Y. 160, 272–80.Google Scholar
Brown, R. D. & Tocchini-Valentini, G. P. (1972). On the role of RNA in gene amplification. Proc. natn. Acad. Sci. U.S.A. 69, 1746–8.Google Scholar
Bruns, G. A. P. & Ingram, V. M. (1973). Erythropoiesis in the developing chick embryo. Devl Biol. 30, 455–9.Google Scholar
Burdon, R. H. & Adams, R. L. P. (1969). In vivo methylation of DNA from mouse fibroblasts. Biochim. biophys. Acta 174, 322–9.Google Scholar
Butterworth, P. H. W., Cox, R. F. & Chesterton, C. J. (1971). Transcription of mammalian chromatin by mammalian DNA-dependent RNA polymerase. Eur.J. Biochem. 23, 229–41.Google Scholar
Campbell, R. D. & David, C. N. (1974). Cell cycle kinetics and development of Hydra attenuata. 2. Interstitial cells. J. Cell Sci. 16, 349–58.Google Scholar
Carlsson, S. A., Luger, O., Ringertz, N. R. & Savage, R. E. (1974 a). Phenotypic expression in chick erythrocyte x rat myoblast hybrids and in chick myoblast x rat myoblast hybrids. Expl Cell Res. 84, 4755.Google Scholar
Carlsson, S. A., Ringertz, N. R. & Savage, R. E. (1974 b). Intracellular antigen migration in interspecific myoblast heterokaryons. Expl Cell Res. 84, 255–66.CrossRefGoogle ScholarPubMed
Church, R. B. & Schultz, G. A. (1974). Differential gene activity in the preand postimplantation mammalian embryo. Curr. Topics Dev. Biol. 8, 179202.CrossRefGoogle Scholar
Clark, R. J. & Felsenfeld, G. (1971). Structure of chromatin. Nature (New Biol.) 229, 101–6.Google Scholar
Conklin, E. G. (1905). The organization and cell lineage of the Ascidian egg. J. Acad. nat. Sci. Philad. 13, 1119.Google Scholar
Cooke, J. (1973). Morphogenesis and regulation in spite of continuous mitotic inhibition in Xenopus embryos. Nature, Lond. 242, 55–6.CrossRefGoogle ScholarPubMed
Crippa, M. (1970). Regulatory factor for the transcription of the ribosomalgenes in Amphibian oocytes. Nature, Lond. 227, 1138–40.Google Scholar
Crippa, M. & Tocchini, Valenitni G. P. (1971). Synthesis of amplified DNA that codes for ribosomal RNA. Proc. natn. Acad. Sci. U.S.A. 68, 2769–773.Google Scholar
Davidson, E. H. (1968). Gene Activity in Early Development. New York: Academic Press.Google Scholar
Dawid, I. B. & Brown, D. D. (1970). The mitochondrial and ribosomal DNA components of oocytes of Urechis caupo. Devl Biol. 22, 114.Google Scholar
Dawid, I. B., Brown, D. D. & Reader, R. H. (1970). Composition and structure of chromosomal and amplified DNA's of Xenopus laevis. J. molec. Biol. 51, 341–60.Google Scholar
De Petrocellis, B. & Parisi, E. (1972). Changes in alkaline deoxyribonuclease activity in sea urchin during embryonic development. Expl Cell Res. 73, 496500.Google Scholar
De Petrocellis, B. & Parisi, E. (1973). Effect of actinomycin and puromycin on the deoxyribonuclease activity in Paracentrotus lividus at various stages of development. Expl Cell Res. 82, 351–6.Google Scholar
De Petrocellis, B. & Monroy, A. (1974). Regulatory processes of DNA synthesis in the embryo. Endeavour 33, 92–8.Google Scholar
Di, Berardino M. A. & Haffner, N. (1970). Origin of the chromosomal abnormalities in nuclear transplants — a re-evaluation of nuclear differentiation and nuclear equivalence in Amphibians. Devl Biol. 23, 185209.Google Scholar
Doering, J. L. & Fischman, D. A. (1974). The in vitro cell fusion of embryonic chick muscle without DNA synthesis. Devl Biol. 36, 225–35.Google Scholar
Driesch, H. (1898). Von der Beendigung morphogener Elementar Processe.Arch. EntwMech. Org. 6, 198227.Google Scholar
Durante, M. (1956). Cholinesterase in the development of Ciona intestinalis (Ascidia). Experientia 12, 307–8.Google Scholar
Ebert, J. D. & Sussex, J. M. (1970). Interacting Systems in Development. New York: Holt, Rinehart & Winston.Google Scholar
Elgin, S. & Bonner, J. (1970). Limited heterogeneity of the major nonhistone chromosomal proteins. Biochemistry, N. Y. 9, 4440–7.Google Scholar
Elsdale, T. R., Fischberg, M. & Smith, S. (1958). A mutation that reduces nucleolar number in Xenopus laevis. Expl Cell Res. 14, 642–3.Google Scholar
Enea, V. & Allfrey, V. G. (1973). Selective synthesis of liver nuclear acidic proteins following glucagon administration in vivo. Nature, Lond. 242, 265–7.Google Scholar
Ephrussi, B. & Weiss, M. C. (1967). Regulation of the cell cycle in mammalian cells: inferences and speculations based on observations of interspecific somatic hybrids. In Control Mechanisms in Developmental Processes 26th Symp. Soc. Devl Biol. Suppl. 1, pp. 136–69.Google Scholar
Fansler, B. & Loeb, L. A. (1969). Sea urchin nuclear DNA polymerase. 2. Changing localization during early development. Expl Cell Res. 57, 305–10.Google Scholar
Fansler, B. & Loeb, L. A. (1972). Sea urchin nuclear DNA polymerase. 4. Reversible association of DNA polymerase with nuclei during the cell cycle. ExplCell Res. 75, 433–41.Google Scholar
Faulhaber, I. (1970). Anreicherung des vegetalisierender Induktionsfactors aus der Gastrula des Krallenfrosches (Xenopus laevis) und Abgrenzung des Molekulargewichtsbereiches durch Gradientenzentrifugation. Hoppe Seyler's Z. physiol. Chem. 351, 588–94.Google Scholar
Flickinger, R. A., Coward, S. J., Miyagi, M., Moser, C. & Rollins, E. (1965). The ability of DNA and chromatin of developing frog embryosto prime for RNA polymerase-dependent RNA synthesis. Proc. natn. Acad. Sci. U.S.A. 53, 783–90.Google Scholar
Fox, T. O., Sheppard, J. R. & Burger, M. M. (1971). Cyclic membrane changes in animal cells: transformed cells permanently display a surface architecturedetected in normal cells only during mitosis. Proc. natn. Acad. Sci. U.S.A. 68, 244–7.Google Scholar
Gall, J. G. (1968). Differential synthesis of the genes for ribosomal RNA during amphibian oogenesis. Proc. natn. Acad. Sci. U.S.A. 60, 553–60.Google Scholar
Gall, J. G. & Pardue, M. L. (1969). Formation and detection of RNA—DNA hybrid molecules in cytological preparations. Proc. natn. Acad. Sci. U.S.A. 63, 378–83.Google Scholar
Georgiev, G. P. (1972). The structure of the transcriptional units in eukaryotic cells. In Curr. Topics Dev. Biol. 7, 160.Google Scholar
Geraci, D., Eremenko, T., Cocchiara, R., Granieri, A., Scarano, E. & Volpe, P. (1974). Correlation between synthesis and methylation of DNA in HeLa cells. Biochem. biophys. Res. Commun. 57, 353–8.Google Scholar
Geyer-Duszynsky, I. (1959). Experimental research on chromosome elimination in Cecidomidae (Diptera). J. exp. Zool. 141, 391447.Google Scholar
Geyer-Duszynska, I. (1966). Genetic factors in oogenesis and spermatogenesis in Cecidomidae. Chromosomes Today I, 174.Google Scholar
Giudice, G. (1962). Reconstitution of whole larvae from disaggregated cellsof sea urchin embryos. Devl Biol., 5 402–11.Google Scholar
Giudice, G. (1973). Developmental Biology of the Sea Urchin Embryo. New York: Academic Press.Google Scholar
Giudice, G., Pirrone, A. M., Roccheri, M. & Trapani, M. (1973). Maturational cleavage of nucleolar ribosomal RNA precursor can be catalysed by non-specific endonuclease. Biochim. biophys. Acta 319, 7280.Google Scholar
Gilmour, R. S. & Paul, J. (1970). Role of non-histone components in determining organ specificity of rabbit chromatins. FEBS Lett. 9, 242–4.Google Scholar
Grippo, P. (1973). Partial purification and properties of two DNA polymerase activities in eggs and oocytes of Xenopus laevis. Abstracts IXth Int. Cong. Biochem. 3m, 34.Google Scholar
Grippo, P., Iaccarino, M., Parisi, E. & Scarano, E. (1968). Methylation of DNA in developing sea urchin embryos. J. molec. Biol. 36, 195208.Google Scholar
Grippo, P. & Lo, Scavo A. (1972). DNA polymerase activity during maturation in Xenopus laevis oocytes. Biochem. biophys. Res. Commun. 48, 280–5.Google Scholar
Grippo, P., Parisi, E., Carestia, C. & Scarano, E. (1970). A novel origin of some deoxyribonucleic acid thymine and its non-random distribution. Biochemistry, N.Y. 9, 2605–9.Google Scholar
Grobstein, C. (1967). The problem of the chemical nature of embryonic inducers. In Cell Differentiation (ed. De Rueck, A. V. S. &Knight, J.), pp. 131–8. Ciba Fdn Symp. London: Churchill.Google Scholar
Grunz, H. (1970). Abhängigkeit der Kompetenz des Amphibien — Ektoderms von der Protein Synthese. Wilhelm Roux' Arch. EntwMech. Org. 165,91102.Google Scholar
Gurdon, J. B. (1964). The transplantation of living nuclei. Adv. Morph. 4, 144.Google Scholar
Gurdon, J. B. (1967). On the origin and persistence of a cytoplasmic state inducing nuclear DNA synthesis in frogs' eggs. Proc. natn. Acad. Sci. U.S.A. 58, 545–52.Google Scholar
Gurdon, J. B. (1969). Nucleic acid synthesis in embryos and its bearing on cell differentiation. Essays Biochem. 4, 2568.Google Scholar
Gurdon, J. B., Birnstiel, M. L. & Speight, V. A. (1969). The replication of purified DNA introduced into living egg cytoplasm. Biochim. biophys. Acta 174, 614–28.Google Scholar
Gurdon, J. B. & Brown, D. D. (1965). Cytoplasmic regulation of RNA synthesis and nucleolus formation in developing embryos of Xenopus iaevis. J. molec. Biol. 12, 2735.Google Scholar
Gurdon, J. B. & Speight, V. A. (1969). The appearance of cytoplasmic DNA polymerase activity during the maturation of amphibian oocytes into eggs. Expl Cell Res. 55, 253–6.Google Scholar
Gurdon, J. B. & Woodland, H. R. (1968). The cytoplasmic controlof nuclear activity in animal development. Biol. Rev. 43, 233–67.Google Scholar
Hagopian, H. K. & Ingram, V. M. (1971). Developmental changes of erythropoiesis in cultured chick blastoderms. J. Cell Biol. 51, 440–51.Google Scholar
Harris, H. (1970). Cell Fusion. Oxford: Clarendon Press.Google Scholar
Harrison, P. R., Birnie, G. D., Hell, A., Humphries, S., Young, B. D. & Paul, J. (1974). Kinetic studies of gene frequency. I. Use of a DNA copy of 9S RNA to estimate globin gene dosage in mouse tissues. J. molec. Biol. 84, 539–54.Google Scholar
Herbert, M. C. & Graham, C. F. (1974). Cell determination and biochemical differentiation of the early mammalian embryo. Curr. Top. Dev. Biol. 8, 151–78. New York: Academic Press.Google Scholar
Heuser, C. H. & Streeter, G. L. (1929). Early stages in the development of pig embryos, from the period of initial cleavage to the time of the appearance of the limb buds. Publs Carnegie Instn no. 394; Contr. Embryol. no. 109, 20, 130.Google Scholar
Holoubek, V. & Croker, T. (1968). DNA associated acidic proteins. Biochim. biophys. Acta 157, 352–61.Google Scholar
Holtzer, H., Weintraub, H. & Biehl, J. (1973). Cell cycle-dependent events during myogenesis, neurogenesis and erythrogenesis. FEBS Symp. 24, 4153. New York: Academic Press.Google Scholar
Holtzer, H., Weintraub, H., Mayne, R. & Mocha, B. (1972). The cell cycle, cell lineages and cell differentiation. Curr. Top. Dev. Biol. 7, 229–56.CrossRefGoogle ScholarPubMed
Hörstadius, S. (1939). The mechanisms of sea urchin development studied by operative methods. Biol. Rev. 14, 132–79.Google Scholar
Huang, R. C. & Bonner, J. (1962). Histone, a suppressor of chromosomal RNA synthesis. Proc. natn. Acad. Sci. U.S.A. 48, 1216–22.Google Scholar
Hughes, M. & Berry, S. J. (1970). The synthesis and secretion of ribosomes by nurse cells of Antheraea polyphemus. Devl Biol. 23, 651–64.Google Scholar
Infante, A. A., Nauta, R., Gilbert, S., Hobart, P. & Firshein, W. (1973). DNA synthesis in developing sea urchins: role of a DNA-nuclear membrane complex. Nature (New Biol.) 242, 58.Google Scholar
Jensen, E. V. & De, Sombre E. R. (1972). Mechanism of the action of the female sex hormone. A. Rev. Biochem. 41, 203–30.Google Scholar
Kafatos, F. C. (1972). The cocoonase zymogen cells of silk moths: a model of terminal cell differentiation for specific protein synthesis. Curr. Topics Dev. Biol. 7, 125191.Google Scholar
Kalousek, F. & Morris, N. R. (1969). The purification and properties of deoxyribonucleic acid methylase from rat spleen. J. biol. Chem. 244,1157–63.Google Scholar
Kamiyama, M. & Wang, T. Y. (1971). Activated transcription fromrat liver chromatin by non-histone proteins. Biochim. biophys. Acta 228, 563–76.Google Scholar
Kappler, J. W. (1970). The kinetics of DNA methylation in cultures of a mouse adrenal cell line. Jl Cell Physiol. 75, 2131.Google Scholar
Kappler, J. W. (1971). The 5-methylcytosine content of DNA: tissue specificity. Jl Cell Physiol. 78, 33–6.Google Scholar
Kaye, A. M., Friedlander, B., Salomon, R. & Bar-Meir, S. (1967). Methylation of DNA in vitro: enzymic activity from different bacterial strains on DNA from various sources. Biochim. biophys. Acta 142, 331–44.Google Scholar
Kedes, L. H., Gross, P. R., Cognetti, G. & Hunter, A. Z. (1969). Synthesis of nuclear and chromosomal proteins on light polyribosomes during cleavage in the sea urchin embryo. J. molec. Biol. 45, 337–51.CrossRefGoogle ScholarPubMed
Kedes, L. H. & Birnstiel, M. L. (1971). Reiteration and clustering of DNA sequences complementary to histone messenger RNA. Nature (New Biol.) 230, 165–9.Google Scholar
King, R. C. (1970). Ovarian Development in Drosophila melanogaster. New York: Academic Press.Google Scholar
Kish, V. M. & Kleinsmith, L. J. (1972). Heterogeneity of nuclear protein kinases associated with non-histone chromatin proteins. J. Cell Biol. 55, 138a.Google Scholar
Kleinsmith, L. J., Heidema, J. & Carrol, A. (1970). Specific binding of rat liver nuclear proteins to DNA. Nature, Lond. 226, 1025–6.Google Scholar
La, Marca M. J., Smith, L. D. & Strobel, M. C. (1973) Quantitative and qualitative changes of RNA synthesis in stage 6 and stage 4 oocytes of Xenopus laevis. Devl Biol. 34, 106–18.Google Scholar
Laskey, R. A. & Gurdon, J. B. (1970). Genetic content of adult somatic cells tested by nuclear transplantation from cultured cells. Nature, Lond. 228, 1332–4.Google Scholar
Levitt, D. & Dorfman, A. (1973). Concepts and mechanisms of cartilage differentiation. Curr. Top. Dev. Biol. 8, 103–49.Google Scholar
Levy, R., Levy, S., Rosemberg, S. & Simpson, R. (1973). Selective stimulation of chromatin protein synthesis in lymphoid cells by phytohemagglutinin. Biochemistry, N.Y. 12, 224–8.Google Scholar
Lin, S. & Riggs, A. D. (1972). Lac operator analogues: bromodeoxyuridine substitution in the lac operator affects the rate of association of the lac repressor. Proc. natn. Acad. Sci. U.S.A. 69, 2574–6.Google Scholar
Loeb, L. A., Fansler, B., Williams, R. & Mazia, D. (1969). Sea urchin nuclear DNA polymerase. 1. Localization in nuclei during rapid DNA synthesis. Expl Cell Res. 57, 298304.Google Scholar
Macgillivary, A. J., Carrol, D. & Paul, J. (1971). The heterogeneity of the non-histone chromatin proteins from mouse tissues. FEBS Lett. 13, 204–7.Google Scholar
Mahdavi, V. & Crippa, M. (1972). An RNA—DNA complex intermediate in ribosomal gene amplification. Proc. natn. Acad. Sci. U.S.A. 69, 1749–52.Google Scholar
Mahowald, A. P. (1968). Polar granules of Drosophila. 2. Ultrastructural changes during early embryogenesis. J. Expl Zool. 167, 237–62.Google Scholar
Mahowald, A. P. (1971). Polar granules of Drosophila. 3. The continuity of polar granules during the life cycle of Drosophila. J. Expl Zool. 176, 329–44.Google Scholar
Marshall, Graves J. A. (1972 a). DNA synthesis in heterokaryons formed by fusion of mammalian cells from different species. Expl Cell Res. 72, 393403.Google Scholar
Marshall, Graves J. A. (1972 b). Cell cycles and chromosome replication patterns in interspecific somatic hybrids. Expl Cell Res. 73, 8194.Google Scholar
Marushige, K. & Dixon, G. H. (1969). Developmental changes in chromosomal composition and template activity during spermatogenesis in trout testis. DevlBiol. 19, 392414.Google Scholar
Marushige, K. & Ozaki, H. (1967). Properties of isolated chromatin from sea urchin embryo. Devl Biol. 16, 474–88.Google Scholar
Miller, O. L. & Beatty, B. R. (1969). Visualization of nucleolar genes. Science, N.Y. 164, 955–7.Google Scholar
Minganti, A. (1959) Androgenetic hybrids in Ascidians. I. Ascidia malaca (♀) × Phallusia mamillata (♂). Acta Embryol. Morph. exp. 2, 244–6.Google Scholar
Mintz, B. (1962). Experimental recombination of cells in the developing mouse egg: normal and lethal mutant genotypes. Am. Zool. 2, 541.Google Scholar
Mintz, B. (1971) Allophenic mice of multi-embryo origin. In Methods in Mammalian Embryology (ed. Daniel, J. C.). San Francisco: W. H. Freeman.Google Scholar
Miura, Y. & Wilt, F. H. (1971). The effects of 5-bromodeoxyuridine on yolk sac erythropoiesis in the chick embryo. J. Cell Biol. 48, 523–32.Google Scholar
Mizuno, S., Lee, Y. R., Whiteley, A. H. & Whiteley, H. R. (1974). Cellular distribution of RNA populations in 16-cell stage embryos of the sand dollar, Dendraster excentricus. Devl Biol. (In the Press.)Google Scholar
Monroy, A. (1965). Chemistry and Physiology of Fertilization London: Holt, Rhinehardt & Winston.Google Scholar
Monroy, A. (1973). Fertilization and its Biochemical Consequences. An Addison-Wesley Module in Biology, no. 7.Google Scholar
Monroy, A. & Maggio, R. (1964). Biochemical studies on the early development of the sea urchin. Adv. in Morphogenesis 3, 95145.Google Scholar
Monroy, A., Ortolani, G., O'Dell, D. S. & Millonig, G. (1973). Binding of Concanavalin A to the surface of unfertilized and fertilized Ascidian eggs. Nature, Lond. 242, 409–10.Google Scholar
Moore, A. R. (1933). Is cleavage rate a function of the cytoplasm or of thenucleus ? J. exp. Biol. 10, 230–6.Google Scholar
Morgan, T. H. (1934). Embryology and Genetics. Columbia University Press.Google Scholar
Moritz, K. B. (1970). DNS-Variation im keimbahnbegrenzten Chromatin und autoradiographische Befunde an seiner Funktion bei Parascaris equorum. Verh. dt. zool. Ges. 64, 3642.Google Scholar
Morris, R. & Pih, C. D. (1971). The preparation of soluble DNA methylase from normal and regenerating rat liver. Cancer Res. 31, 433440.Google Scholar
Moscona, A. A. (1973). Induction of glutamine synthetase in embryonic neural retina: a model for the regulation of specific gene expression in embryonic cells. FEBS Symp. 24, Biochemistry of Cell Differentiation (ed. Monroy, A. and Tsanev, R.), pp. 123. London and New York: Academic Press.Google Scholar
Neyfakh, A. A. (1971). Steps of realization of genetic information in early development. Curr. Top. Dev. Biol. 6, 4577.Google Scholar
Noonan, K. D., Levine, A. J. & Burger, M. M. (1973). Cell-cycle-dependent changes in the surface membrane as detected by the [3H] Concanavalin A. J. Cell Biol. 58, 491–7.CrossRefGoogle ScholarPubMed
Noronha, J. M., Sheys, G. H. & Buchanan, J. M. (1972). Induction of a reductive pathway for deoxyribonucleotide synthesis during early embryo- genesis of the sea urchin. Proc. natn. Acad. Sci. U.S.A. 69, 2006–10.Google Scholar
Oda, K. & Marmur, J. (1966). Purification and properties of deoxyribonucleic acid amethylase from Bacillus subtilis. Biochemistry, N.Y. 5, 761–72.Google Scholar
O'Dell, D. S., Ortolani, G. & Monroy, A. (1974). Increased binding of radioactive Concanavalin A during maturation of Ascidia eggs. Expl Cell Res. 83, 408–11.Google Scholar
Ortolani, G. (1954). Risultati definitivi sulla distribuzione dei territori presuntivi degli organi del germe di Ascidia allo stadio 8, determinati con le macchieal carbone. Pubbl. Staz. zool. Napoli 25, 161–87.Google Scholar
Ortolani, G. (1955). The presumptive territory of the mesoderm in the Ascidian germ. Experientia II, 445.Google Scholar
Ortolani, G. (1962). Territorio presuntivo del sistema nervoso nelle larve di Ascidie. Acta Embryol. Morph. exp. 5, 189–98.Google Scholar
Paul, J. & Gilmour, R. S. (1968). Organ-specific restriction of transcription in mammalian chromatin. J. molec. Biol. 34, 305–16.Google Scholar
Platz, R., Stein, G. S. & Kleinsmith, L. S. (1973). Changes in the phosphorylation of non-histone chromatin proteins during the cell cycle of HeLa S3 cells. Biochem. biophys. Res. Commun. 51, 735–40.Google Scholar
Richter, K. H. & Sekeris, C. E. (1972). Isolation and partial purification of non-histone chromosomal proteins from rat liver, thymus and kidney. Archs Biochim. Biophys. 148, 4453.Google Scholar
Rovera, G. & Baserga, R. (1971). Early changes in the synthesis of acidic nuclear proteins in human diploid fibroblasts stimulated to synthesize DNA by changing medium. J. Cell Physiol. 77, 201–11.Google Scholar
Saxén, L. (1971). Inductive interactions in kidney development. Symp. Soc. exp. Biol. no. 25, pp. 207–21. Cambridge University Press.Google Scholar
Saxén, L. & Toivonen, S. (1962). Primary Embryonic Induction. London: Academic Press.Google Scholar
Scarano, E. (1969). Enzymatic modifications of DNA and embryonic differentiation. Annales d'Embryologie et de Morphogenese, Supp. 1, 5161.Google Scholar
Scarano, E. (1971). The control of gene function in cell differentiation and embryogenesis. Advances in Cytopharmacology, vol. I (ed. Clementi, F. and Ceccarelli, B.), p. 14. New York: Raven Press.Google Scholar
Scarano, E., De, Petrocellis B. & Augusti-Tocco, G. (1964 a). Studies on the control of enzyme synthesis during the early embryonic development of the sea urchin. Biochim. biophys. Acta 83, 174–6.Google Scholar
Scarano, E., De, Petrocellis B. & Augusti-Tocco, G. (1964 b). Deoxycytidylate aminohydrolase content in disaggregated cells from sea urchin embryos. Expl Cell Res. 36, 211–13.Google Scholar
Scarano, E., Iaccarino, M., Grippo, P. & Parisi, E. (1967). The heterogeneity of thymine methyl group origin in DNA pyrimidine isostichs of developing sea urchin embryos. Proc. natn. Acad. Sci. U.S.A. 57, 1394–400.Google Scholar
Scarano, E., Iaccarino, M., Grippo, P. & Winkelmans, D. (1965). On methylation of DNA during development of sea urchin embryo. J. molec. Biol. 14, 603–7.Google Scholar
Scarano, E. & Maggio, R. (1959). The enzymatic deamination of 5′-deoxycytidylic acid and of 5-methyl-5′-deoxycytidylic acid in the developing sea urchin embryo. Expl Cell Res. 18, 333–46.Google Scholar
Scarano, E., Rossi, M. & Geraci, G. (1968). The regulation of the activity of deoxycytidylate aminohydrolase. In FEBS Symp. on Regulation of Enzyme Activity and Allosteric Interactions (ed. Kvamme, E. and Pihl, A.), pp. 145–65. New York: Academic Press.Google Scholar
Scarano, E., Talarico, M., Bonaduce, L. & De, Petrocellis B. (1960). Enzymatic deamination of 5′-deoxycytidylic acid and of 5-methyl-5′- deoxycytidylate acid in growing and in non-growing tissues. Nature, Lond. 186, 237–8.Google Scholar
Schaller, H. (1973). Isolation and characterization of a low-molecular- weight substance activating head and bud formation in hydra. J. Embryol. exp. Morph. 29, 2738.Google Scholar
Schaller, H. & Gierer, A. (1973). Distribution of head-activating substance in hydra and its localization in membranous particles in nerve cells. J. Embryol. exp. Morph. 29, 3952.Google Scholar
Schultz, G., Manes, C. & Hahn, W. E. (1973). Synthesis of RNA containing polyadenylic acid sequences in preimplantation rabbit embryos. Devl Biol. 30, 418–26.Google Scholar
Sconzo, G., Bono, A., Albanese, I. & Giudice, G. (1972). Studies on sea urchin oocytes. 2. Synthesis of RNA during oogenesis. Expl Cell Res. 72, 95100.Google Scholar
Sconzo, G. & Giudice, G. (1971). Synthesis of ribosomal RNA in sea urchin embryos. 5. Further evidence for an activation following the hatching blastula stage. Biochim. biophys. Acta 254, 447–51.Google Scholar
Sconzo, G., Pirrone, A., Mutolo, V. & Giudice, G. (1970 a). Synthesis of ribosomal RNA during sea urchin development. 3. Evidence for an activation of transcription. Biochim. biophys. Acta 199, 435–40.Google Scholar
Sconzo, G., Pirrone, A., Mutolo, V. & Giudice, G. (1970 b). Synthesis of ribosomal RNA in disaggregated cells of sea urchin embryos. Biochim. biophys. Acta 199, 441–6.Google Scholar
Shea, M. & Kleinsmith, L. S. (1973). Template-specific stimulation of RNA synthesis by phosphorylated non-histone chromatin proteins. Biochem. biophys. Res. Commun. 50, 473–77.Google Scholar
Sheid, B., Srinivasan, P. R. & Borek, E. (1968). Deoxyribonucleic acid methylase of mammalian tissues. Biochemistry, N. Y. 7, 280–5.Google Scholar
Shelton, K. R. & Allfrey, V. G. (1970). Selective synthesis of a nuclear acidic protein in liver cells stimulated by cortisol. Nature, Lond. 228, 132–4.Google Scholar
Shelton, K. R. & Neelin, J. M. (1971). Nuclear residual proteins from goose erythroid cells and liver. Biochemistry, N.Y. 10, 2342–7.Google Scholar
Silagi, S. & Bruce, S. A. (1970). Suppression of malignancy and differentiation in melanotic melanoma cells. Proc. natn. Acad. Sci. U.S.A. 66, 72–8.Google Scholar
Spelsberg, T. C. & Hnilica, L. S. (1970). Deoxyribonucleoproteins and the tissue-specific restriction of the deoxyribonucleic acid in chromatin. Biochem. J. 120, 435–7.Google Scholar
Spemann, H. (1936). Experimentelle Beiträge zu elner Theorie der Entwicklung. Berlin: Springer-Verlag.Google Scholar
Stein, G. S. & Baserga, R. (1970). The synthesis of acidic nuclear proteins in the prereplicative phase of the isoproterenol-stimulated salivary glands. J. biol. Chem. 245, 6097–105.Google Scholar
Stein, G. & Baserga, R. (1972). Nuclear proteins and the cell cycle. Adv. Cancer Res. 15, 287330.Google Scholar
Stein, G. & Farber, J. (1972). Role of non-histone chromosomal proteins in the restriction of mitotic chromatin template activity. Proc. natn. Acad. Sci. U.S.A. 69, 2918–21.Google Scholar
Stein, G. S. & Hunter, G. D. (1973). Chromosomal protein binding and regulation of transcription during the cell cycle of HeLa S3 cells. Fedn Proc. no. 2217.Google Scholar
Stellwagen, R. H. & Tomkins, G. M. (1971). Preferential inhibition by 5-bromodeoxyuridine of the synthesis of tryosine aminotransferase in hepatoma cell cultures. J. molec. Biol. 56, 167–82.Google Scholar
Tarkowski, A. K. (1961). Mouse chimeras developed from fused eggs. Nature, Lond. 190, 857–60.Google Scholar
Tarkowski, A. K. & Wrobleska, J. (1967). Development of blastomeres of mouse eggs isolated at the 4- and 8-cell stage. J. Embryol. exp. Morph. 18, 155–80.Google Scholar
Teng, C. & Hamilton, T. H. (1969). Role of chromatin in estrogen action in the uterus. Hormone-induced synthesis of non-histone acidic proteins which restore histone-inhibited DNA dependent RNA synthesis. Proc. natn. Acad. Sci. U.S.A. 63, 465–72.Google Scholar
Teng, C. S., Teng, C. T. & Allfrey, V. G. (1971). Studies on nuclear acidic proteins. J. biol. Chem. 246, 3597–609.Google Scholar
Tiedemann, H. (1966). The molecular basis of differentiation in early development of Amphibian embryos. Curr. Top. Dev. Biol. I, 85112.Google Scholar
Tiedemann, H. (1968). Factors determining embryonic differentiation. Jl Cell Physiol., Suppl. 1, 72, 129–44.Google Scholar
Tobler, H., Smith, K. D. & Ursprung, H. (1972). Molecular aspects of chromatin elimination in Ascaris lumbricoides. Devl Biol. 27, 190203.Google Scholar
Tosi, L., Granieri, A. & Scarano, E. (1972). Enzymatic DNA modifications in isolated nuclei from developing sea urchin embryos. Expl Cell Res. 72, 257–64.Google Scholar
Tosi, L. & Scarano, E. (1973). Effect of trypsin on DNA methylation in isolated nuclei from developing sea urchin embryos. Biochem. biophys. Res. Commun. 55, 470–6.Google Scholar
Tsubai, A. & Baserga, R. (1972). Synthesis of nuclear acidic proteins in density-inhibited fibroblasts stimulated to proliferate. Jl Cell Physiol. 80, 107–17.Google Scholar
Vanyushin, B. F., Tkacheva, S. V. & Belozersky, A. N. (1970). Rare bases in animal DNA. Nature, Lond. 225, 948–9.Google Scholar
Vanyushin, B. F., Mazin, A. L., Vasilyev, V. K. & Belozersky, A. N. (1973). The content of 5-methylcytosine in animal DNA: the species and tissue specificity. Biochim. biophys. Acta 229, 397.Google Scholar
Vincent, W. S., Halvorson, H. O., Chen, H. R. & Shin, O. (1969). A comparison of ribosomal gene amplification in uni- and multinucleolate oocytes. Exptl Cell Research 57, 240–50.Google Scholar
Vittorelli, M. L., Cannizzaro, G. & Giudice, G. (1973). Trypsin treatment of cells dissociated from sea urchin embryos elicits DNA synthesis. Celt Differ. 2, 279–84.Google Scholar
Wang, T. Y. (1968). Restoration of histone-inhibited DNA-dependent RNA synthesis by acidic chromatin proteins. Exptl Cell Research 53, 288–91.Google Scholar
Wang, T. Y. (1970). Activation of transcription in vitro from chromatin by non-histone proteins. Expl Cell Res. 61, 455–7.Google Scholar
Wang, T. Y. (1971). Tissue specificity of non-histone chromosomal proteins. Expl Cell Res. 69, 217–19.Google Scholar
Wartiovaara, J., Nordling, S., Lehtonen, E. & Saxén, L. (1974). Transfilter induction of kidney tubules: correlation with cytoplasmic penetration into nucleopore filters. J. Embryol. exp. Morph. 31, 667–82.Google Scholar
Whittaker, J. R. (1973 a). Segregation during ascidian embryogenesis of egg cytoplasmic information for tissue-specific enzyme development. Proc. natn. Acad. Sci. U.S.A. 70, 2096–100.Google Scholar
Whittaker, J. R. (1973 b). Tyrosinase in the presumptive pigment cells of Ascidian embryos; tyrosine accessibility may initiate melanin synthesis. Devl Biol. 30, 441–54.Google Scholar
Wilhelm, J. A., Ansevin, A. T., Johnson, A. W. & Hnilica, L. A. (1972). Proteins of chromatin in genetic restriction. Comparison of histone and non-histone proteins of rat liver nucleolar and extranucleolar chromatin. Biochem. biophys. Acta 272, 220–30.Google Scholar
Wilson, E. B. (1906). The Cell in Development and Inheritance. New York: Macmillan Co.Google Scholar
Wolpert, L. (1971). Positional information and pattern formation. Curr. Top. Dev. Biol. 6, 183224.Google Scholar
Zeuthen, E. (1951). Segmentation, nuclear growth and cytoplasmic storage in eggs of echinoderms and amphibia. Pubbl. Star. zool. Napoli 23, 4769.Google Scholar