The relation of a particular chromosomal element to the development of the nucleoli in Zea mays

  • Barbara McClintock


  1. 1.

    The nucleolus is organized in the telophase through the activity of a distinct deep-staining body having a definite position in one chromosome (the satellited chromosome) of the monoploid complement. Correlated with the number of satellited chromosomes present, the telophases of somatic tissue of haploids show one nucleolus, diploids, two nucleoli and triploids, three nucleoli. That the nucleolus develops through the activity of this body (refered to as the nucleolar-organizing body or element) was obtained from a reciprocal translocation which broke this body into two parts. Both interchanged chromosomes possessed a section. Nucleoli developed from each of these two segments. Thus, plants homozygous for the interchange developed four nucleoli in their somatic telophases; plants heterozygous for the interchange developed three nucleoli in their somatic telophases. Similarly, the telophase nucleoli resulting from the first division within the monoploid microspore of normal diploids show only one nucleolus, whereas, those of plants homozygous for the interchange are characterized by the development of two nucleoli.

  2. 2.

    The functional capacity to develop a nucleolus is not the same for both segments of the severed nucleolar-organizing body. This is evident when the two interchanged chromosomes are present in the same nucleus. The segment of the nucleolar-organizing body possessed by one interchanged chromosome produced a large nucleolus, whereas, the segment of the nucleolar-organizing body possessed by the other interchanged chromosome produced a small nucleolus. When this latter chromosome, with the nucleolar-organizing element of slower rate of functional capacity is present without the former (i. e. without a competing nucleolarorganizing element) it produces, in contrast, a large nucleolus.

  3. 3.

    The activity of the nucleolar-organizing element is hindered by certain genomic deficiencies. When this occurs, many small nucleolarlike bodies are produced and remain associated with the other chromosomes of the complement. These small nucleoli appear to develop from a swelling and later collection into droplets of the matrix substance of the chromosome.



Slow Rate Functional Capacity Somatic Tissue Reciprocal Translocation Matrix Substance 
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Literature cited

  1. Baranor, P.: Das Verhalten des Nucleolus von Galtonia candicans während der Reduktionsteilung. Ber. dtsch. bot. Ges. 43, 483–489 (1925).Google Scholar
  2. —: Zytologische und embryologische Untersuchungen an Drimiopsis maculata Lindl. Z. Zellforsch. 3, 131–148 (1926).Google Scholar
  3. Creighton, H. B. and B. McClintock: A correlation of cytological and genetical crossing-over in Zea mays. Proc. Nat. Acad. Sci. U.S.A. 17, 492–497 (1931).Google Scholar
  4. Dawydov, W.: Die Entwicklung des Kernes in den Zellen der Rochschen Organe im Zusammenhang mit den allgemeinen Grundsätzen des Baues des somatischen Kernes der Larve von Mycetobia pallipes Meig. Z. Zellforsch. 10, 625–641 (1930).Google Scholar
  5. Dermen, H.: Origin and behavior of the nucleolus in plants. J. Arnold Arboretum 14, 282–319 (1933).Google Scholar
  6. Geitler, L.: Das Verhalten der Nukleolen in einer tetraploiden Wurzel von Crepis capillaris. Planta (Berl.) 17, 801–804 (1932).Google Scholar
  7. Heitz, E.: Die Ursache der gesetzmäßigen Zahl, Lage, Form und Größe pflanzlicher Nukleolen. Planta (Berl.) 12, 775–844 (1931a).Google Scholar
  8. —: Nukleolen und Chromosomen in der Gattung Vicia. Planta (Berl.) 15, 495–505 (1931b).Google Scholar
  9. —: Die somatische Heteropyknose bei Drosophila melanogaster und ihre genetische Bedeutung. Z. Zellforsch. 20, 237–287 (1933).Google Scholar
  10. Kaufmann, B. P.: Interchange between X- and Y-chromosomes in attached X-females of Drosophila melanogaster. Proc. Nat. Acad. Sci. U.S.A. 19, 830–838 (1933).Google Scholar
  11. Kuhn, E.: Zur Zytologie von Thalictrum. Jb. Bot. 68, 382–430 (1928).Google Scholar
  12. Marshak, A. G.: The morphology of the chromosomes of Pisum sativum. Cytologia 2, 318–339 (1931).Google Scholar
  13. McClintock, B.: A method for making aceto-carmin smears permanent. Stain. Tech. 4, 53–56 (1929).Google Scholar
  14. —: Cytological observations of deficiencies involving known genes, translocations and an inversion in Zea mays. Missouri Agricult. Exper. Stat. Bull. 163, 1–30 (1931).Google Scholar
  15. —: The association of non-homologous parts of chromosomes in the mid-prophase of meiosis in Zea mays. Z. Zellforsch. 19, 191–237 (1933).Google Scholar
  16. Metz, C. W.: Observations on spermatogenesis in Drosophila. Z. Zellforsch. 4, 1–28 (1927).Google Scholar
  17. Mol, W. E. de: On chromosomal constrictions, satellites and nucleoli in Hyacinthus orientalis. Beitr. Biol. Pflanz. 15, 93–115 (1927a).Google Scholar
  18. —: Somatic segregation together with alteration of the chromosomal complement and of the nucleolar composition. Z. Abstammgslehre 45, 160–183 (1927b).Google Scholar
  19. —: Nucleolar number and size in diploid, triploid and aneuploid Hyancinths. Cellule 38, 1–64 (1927c).Google Scholar
  20. Nawaschin, M.: Morphologische Kernstudien der Crepis-Arten in bezug auf die Artbildung. Z. Zellforsch. 2, 98–111 (1925).Google Scholar
  21. —: Über die Veränderung von Zahl und Form der Chromosomen infolge der Hybridisation. Z. Zellforsch. 6, 195–233 (1927).Google Scholar
  22. Nawaschin, S.: Über den Dimorphismus der Zellkerne in den somatischen Zellen von Galtonia candicans. Bull. Acad. Sci. Petersbourg, VI s. 6, 373–385 (1912).Google Scholar
  23. —: Zellkerndimorphismus bei Galtonia candicans Des. und einigen verwandten Monokotylen. Vortrag von 1913 in Ber. dtsch. bot. Ges. 45, 415–428 (1927).Google Scholar
  24. Richards, A.: The history of the chromosomal vesicles in Fundulus and the theory of genetic continuity of chromosomes. Biol. Bull. (Wood's Hole) 32, 249–290 (1917).Google Scholar
  25. Sax, K.: The cytological mechanism of crossing over. J. Arnold Arboretum 13, 180–212 (1932).Google Scholar
  26. Senjaninova, M.: Das Verhalten des Nukleolus und der Trabanten während der somatischen Mitosen und den Reifeteilungen bei Ranunculus acer L. Z. Zellforsch. 3, 417–430 (1926).Google Scholar
  27. Smith, F. H.: The relation of the satellites to the nucleolus in Galtonia candicans. Amer. J. Bot. 20, 188–195 (1933).Google Scholar
  28. Sorokine, H.: Satellites of somatic mitoses in Ranunculus acris L. Publ. Fac. Sci. Univ. Charles. 13, 1–15. Prague 1924.Google Scholar
  29. —: Idiograms, nucleoli, and satellites of certain Ranunculaceae. Amer. J. Bot. 16, 407–420 (1929).Google Scholar
  30. Stevens, N. M.: Studies in spermatogenesis with special reference to the „accessory chromosome“. Publ. Carnegie Institut. of Washington (U.S.A.) 36, 1–32 (1905).Google Scholar

Copyright information

© Springer-Verlag 1934

Authors and Affiliations

  • Barbara McClintock
    • 1
  1. 1.California Institute of TechnologyPasadena

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