Abstract
Chromosome-associated paraorystalloids are regularly found in the spermatocytes of snails which were reared in the laboratory. They seem to be largely specific for the male gametocytes as they have been observed only in few cases in the oocytes. It is likely that paracrystalloids are formed during pachytene at the site of large heterochromatic knobs which originate by fusion of heterochromatic terminal segments of some bivalents. During diplotene they are always connected with the telomeres of three or four bivalents, thus forming a large trefoil-like structure. During metaphase I paracrystalloids are shed off from the chromosomes and transferred to the cytoplasm. In early spermatids they are found again in the nuclei, where they “fade away” during spermiogenesis. Histochemically they consist of basic proteins, which are probably crystallized in the cubic system. Radioactive labeling of the structure could not be achieved, neither by 3H-uridine or thymidine, nor by amino acids. The functional significance of this peculiar structure is unknown. Certain features justify a comparison with synaptonemal polycomplex
Similar content being viewed by others
References
Adam, H., Czihak, G.: Arbeitsmethoden der makroskopischen und mikroskopischen Anatomie. Stuttgart: G. Fischer 1964
Bergold, G. H.: The molecular structure of some insect virus inclusion bodies. J. Ultrastruct. Res. 8, 360–378 (1963)
Bernhard, W.: A new staining procedure for electron microscopical cytology. J. Ultrastruct. Res. 27, 250–265 (1969)
Bloch, D. P., Hew, H. Y. C.: Schedule of spermatogenesis in the pulmonate snail Helix aspersa, with special reference to histone transition. J. biophys. biochem. Cytol. 7, 515–532 (1960)
Bloom, F. E., Aghajanian, G. K.: Cytochemistry of synapses: selective staining for electron microscopy. Science 154, 1575–1577 (1966)
Eberl-Rothe, G.: Eiweißkristalle in tierischen und menschlichen Zellen. Protoplasmatologia II/B/2bγ, Wien: Springer 1966
Fiil, A., Moens, P. B.: The development, structure and function of modified synaptonemal complexes in mosquito oocytes. Chromosoma (Berl.) 41, 37–62 (1973)
Fuge, H.: A crystalloid component in the meiotic spindle. Exp. Cell Res. 60, 309–313 (1970)
Hauser, M.: The intranuclear mitosis of the ciliates Paracineta limbata and Ichthyophthirius multifiliis. Chromosoma (Berl.) 36, 158–175 (1972)
Hinegardner, R.: Cellular DNA content of the mollusca. Comp. Biochem. Physiol. 47A, 447–460 (1974)
Jones, K. W.: The induction of paracrystalline thread-complexes in the nuclei of amphibian cells by actinomycin D and other DNA-binding antibiotics. J. Ultrastruct. Res. 18, 71–84 (1967)
Lima-de-Faria, A.: DNA replication and gene amplification in heterochromatin. In: Handbook of molecular cytology (A. Lima-de-Faria, ed.) Amsterdam-London: North-Holland Publishing Company 1969
Malawista, St. E., Sato, H.: Vinblastine produces uniaxial, birefringent crystals in starfish oocytes. J. Cell Biol. 42, 596–599 (1969)
Merton, H.: Die Wanderung der Geschlechtszellen in der Zwitterdrüse von Planorbis. Z. Zellforsch. 10, 527–551 (1930)
Moens, P. B.: Multiple core complexes in grasshopper spermatocytes and spermatids. J. Cell Biol. 40, 542–551 (1969)
Moses, M.: Synaptinemal complex. Ann. Rev. Genet. 2, 363–412 (1968)
Price, D. J.: Differential staining of meiotic chromosomes in Cepaea nemoralis L. Caryologia (Firenze) 27, 211–216 (1974)
Smith, U., Smith, D. S.: A microtubular complex in the epidermal nucleus of an insect, Carausius morosus. J. Cell Biol. 26, 961–967 (1965)
Starke, F. J.: Elektronenmikroskopische Untersuchungen der Zwittergonadenacini von Planorbarius corneus L. (Basommatophora). Z. Zellforsch. 119, 483–514 (1971)
Summers, M. D., Arnott, H. J.: Ultrastructural studies on inclusion formation and virus occlusion in nuclear polyhedrosis and granulosis virus-infected cells of Trichoplusia ni (Hübner). J. Ultrastruct. Res. 28, 462–480 (1969)
Thaler,I.: Eiweißkristalle in Pflanzenzellen. Protoplasmatologia II/B/2bγ. Wien: Springer 1966
Weber, F.: Korrelierte Formveränderungen von Nukleolus und nukleohisassoziiertem Heterochromatin bei der Gattung Carabus (Coleoptera). Chromosoma (Berl.) 34, 261–273 (1971)
Welsch, B.: An intranuclear paracrystalloid body in the gametocytes of Panorpa communia (Mecoptera). Chromosoma (Berl.) 48, 107–118 (1974)
Wergin, W. P., Gruber, P. J., Newcomb, E. H.: Fine structural investigations of nuclear inclusions in plants. J. Ultrastruct. Res. 30, 533–557 (1970)
Westergaard, M., von Wettstein, D.: The synaptinemal complex. Ann. Rev. Genet. 6, 71–110 (1972)
Author information
Authors and Affiliations
Additional information
Dedicated to Professor B. Rensch on the occasion of his 75th birthday
Rights and permissions
About this article
Cite this article
Bottke, W. Chromosome-associated paracrystalline nuclear inclusions in the spermatocytes of a pulmonate snail, Planorbarius corneus L.. Chromosoma 55, 273–287 (1976). https://doi.org/10.1007/BF00300394
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00300394