Abstract
Human meiotic prophase spermatocyte nuclei were studied by electron microscope autoradiography after a 3 hours 3H-uridine labeling pulse, followed by postincubation in non-radioactive medium. In autosomes, 3H-uridine nucleolar labeling reaches a peak during early-middle zygotene prior to the peak labeling of chromosomal RNA species at middle pachytene. Transcription activities of sex chromosomes are inconspicuous when compared with that of autosomes. An increasing condensation of nucleolar-associated chromatin in acrocentric bivalents contributes to the formation of basal knobs in human pachytene spermatocytes. Upon completion of knob formation, nucleolar components segregate and the uptake of 3H-uridine decreases. These findings suggest that the template capability of ribosomal DNA cistrons, located next to the basal knob region, is largely associated with a dispersed state of chromatin whereas increased chromatin condensation is correlated with a restriction of ribosomal RNA transcription.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Busch, H., Smetana, K.: The Nucleolus. New York: Academic Press 1970
Ferguson-Smith, M. A.: The sites of nucleolus formation in human pachytene chromosomes. Cytogenetics 3, 124–134 (1964)
Henderson, A. S., Eicher, E. M., Yu, M. T., Atwood, K. C.: The chromosomal location of ribosomal DNA in the mouse. Chromosoma (Berl.) 49, 155–160 (1974)
Henderson, A. S., Warburton, D., Atwood, K. C.: Location of ribosomal DNA of the human chromosome complement. Proc. nat. Acad. Sci. (Wash.) 69, 3394–3398 (1972)
Kierszenbaum, A. L., Tres, L. L.: Nucleolar and perichromosomal RNA synthesis during meiotic prophase in the mouse testis. J. Cell Biol. 60, 39–53 (1974a)
Kierszenbaum, A. L., Tres, L. L.: Transcription sites in spread meiotic prophase chromosomes from mouse spermatocytes. J. Cell Biol. 63, 923–935 (1974b)
Levan, A., Hsu, T. C., Stich, H. F.: The idiogram of the mouse. Hereditas (Lund) 48, 677–689 (1962)
Luciani, J. M.: Les chromosomes meíotiques de l'homme. I. La meíosis normale. Ann. Génét. 13, 101–111 (1970a)
Luciani, J. M.: Les chromosomes meíotiques de l'homme. II. Le nucléole. Les chiasmas. III. La sterélité masculine. Ann. Génét. 13, 169–182 (1970b)
Monesi, V.: Synthetic activities during spermatogenesis in the mouse. Exp. Cell Res. 39, 197–224 (1965)
Moses, M. J., Counce, S. J., Paulson, D. F.: Synaptonemal complex complement of man in spreads of spermatocytes, with details of the sex chromosome pair. Science 187, 363–365 (1975)
Noel, J. S., Dewey, W. C., Abel, J. H., Thompson, R. P.: Ultrastructure of the nucleolus during the Chinese hamster cell cycle. J. Cell Biol. 49, 830–847 (1971)
Ohno, S., Kaplan, W., Kinosita, R.: Heterochromatic regions and nucleolus organizers in chromosomes of the mouse, Mus musculus. Exp. Cell Res. 13, 358–364 (1957)
Pardue, M. L., Gall, J. G.: Chromosomal localization of mouse satellite DNA. Science 168, 1356–1358 (1970)
Recher, L., Whitescarver, J., Briggs, L.: A cytochemical and radioautographic study of human tissue culture nucleoli. J. Cell Biol. 45, 479–492 (1970)
Salpeter, M. M., Bachmann, L.: Autoradiography. In: Principles and techniques of electron microscopy. Biological applications (M. A. Hayat, ed.), vol. 2, p. 221–278. New York: Van Nostrand Reinhold Company 1972
Simard, R., Bernhard, W.: The phenomenon of nucleolar segregation. Specific action of certain antimetabolites. Int. J. Cancer 1, 463–479 (1966)
Solari, A. J.: The morphology and ultrastructure of the sex vesicle in the mouse. Exp. Cell Res. 36, 160–168 (1964)
Solari, A. J., Tres, L. L.: The ultrastructure of the human sex vesicle. Chromosoma (Berl.) 22, 16–37 (1967)
Solari, A. J., Tres, L. L.: The three-dimensional reconstruction of the XY chromosomal pair in human spermatocytes. J. Cell Biol. 45, 43–53 (1970a)
Solari, A. J., Tres, L. L.: Ultrastructure and histochemistry of the nucleus during male meiotic prophase. In: The human testis (E. Rosenberg and A. Paulsen, eds.), p. 127–138. New York: Plenum Press 1970 b
Tres, L. L.: Estudio ultraestructural e histoquímico de las etapas premeióticas y meióticas de la espermatogenesis humana. Thesis. Facultad de Medicina, Universidad de Buenos Aires 1970
Utakoji, T.: Chronology of nucleic acid synthesis in meiosis of the male Chinese hamster. Exp. Cell Res. 42, 585–596 (1966)
Wallace, H., Birnstiel, M. L.: Ribosomal cistrons and nucleolar organizer. Biochim. biophys. Acta (Amst.) 114, 296–310 (1966)
Wisse, E., Tates, A.D.: A gold latensification-Elon ascorbic acid developer for Ilford L4 emulsion. Proc. 4th. Europ. Reg. Conf. Electron Microscopy, Rome, p. 465–466 (1968)
Wollam, D. H. M., Ford, E. H. R.: The fine structure of the mammalian chromosome in meiotic prophase with special reference to the synaptinemal complex. J. Anat. 98, 163–173 (1964)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Tres, L.L. Nucleolar RNA synthesis of meiotic prophase spermatocytes in the human testis. Chromosoma 53, 141–151 (1975). https://doi.org/10.1007/BF00333042
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00333042