Abstract
Male meiosis, with special regard to the centromeric heterochromatin and to centromeric structure, has been studied in the salamander, Plethodon cinereus cinereus. In this salamander, n = 14. Early meiotic prophase proceeds as described by other authors. Pachytene is followed by a “diffuse” stage in which much of the chromosomal DNA becomes reorganized into fine lateral loops which spring from the bivalent axes. These loops can be seen along the bivalent axes as early as zygotene. Loops are maximally extended in the diffuse stage. The formation of diplotene bivalents involves a return of this extended DNA into the axes of the bivalents. — At leptotone, centromeric heterochromatin is in one or a few large masses. These masses break up during zygotene. At pachytene there is one mass of heterochromatin at the centromeric region of each bivalent. The heterochromatin remains condensed in the diffuse stage. During diplotene, centromeric heterochromatin becomes less conspicuous, and it is possible to see 4 centromere granules in each diplotene bivalent. These observations support the view that centromeres replicate at pre-meiotic S-phase when the associated hetero-chromatin is replicated. In the interphase before the 2nd division, the hetero-chromatin often forms a broken ring corresponding to the positions of the centromeres at the end of anaphase 1. There are 14 masses of heterochromatin in nuclei at prophase of the 2nd division. In spermatids, the heterochromatin appears as a single solid mass or a broken ring.
Similar content being viewed by others
References
Bajer, A., Molè-Bajer, J.: Formation of spindle fibers, kinetochore orientation and behaviour of the nuclear envelope during mitosis in endosperm. Chromosoma (Berl.) 27, 448–484 (1969).
Barry, E. G.: The diffuse diplotene stage of meiotic prophase in Neurospora. Chromosoma (Berl.) 26, 119–129 (1969).
Brinkley, B. R., Stubblefield, E.: Ultrastructure and interaction of the kinetochore and centriole in mitosis and meiosis. Advanc. Cell Biol. 1, 119–185 (1970).
Burger, J. W.: The relation of germ cell degeneration to modifications of the testicular structure of plethodontid salamanders. J. Morph. 60, 459–487 (1937).
Callan, H. G., Lloyd, L.: Lampbrush chromosomes of crested newts Triturus cristatus (Laurenti). Phil. Trans. B 243, 135–219 (1960).
— Taylor, J. H.: A radioautographic study of the time course of male meiosis in the newt Triturus vulgaris. J. Cell Sci 3, 615–626 (1968).
Conger, A. D., Fairchild, L. M.: A quick-freeze method for making smear slides permanent. Stain Technol. 28, 281–283 (1953).
Donnelly, G. M., Sparrow, A. H.: Mitotic and meiotic chromosomes of Amphiuma. J. Hered. 56, 90–98 (1965).
Eisen, G.: The spermatogenesis of Batrachoseps. J. Morph. 17, 1–117 (1900).
Gall, J. G.: Lampbrush chromosomes from oocyte nuclei of the newt. J. Morph. 94, 283–352 (1954).
Highton, R.: Revision of North American salamanders of the genus Plethodon. Bull. Fla. St. Mus. Biol. Sci. 6, 285–288 (1962).
Janssens, F. A.: Évolution des auxocytes mâles du Batrachoseps attenuatus. Cellule 22, 377–425 (1905).
— Dumez, R.: L'élément nucléinien pendent les cinèses de maturation des spermatocytes chez Batrachoseps attenuatus et Plethodon cinereus. Cellule 20, 419–461 (1903).
Kingsbury, B. F.: The spermatogenesis of Desmognathus fusca. Amer. J. Anat. 1, 97–135 (1902).
La Cour, L.: Acetic-orcein: a new stain-fixative for chromosomes. Stain Teehnol. 16, 169–174 (1941).
Levan, A., Fredga, K., Sandberg, A. A.: Nomenclature for centromeric position on chromosomes. Hereditas (Lund) 52, 201–220 (1964).
Luykx, P.: The structure of the kinetochore in meiosis and mitosis in Urechis eggs. Exp. Cell Res. 39, 643–657 (1965).
- Cellular mechanisms of chromosome distribution. Suppl. 2, Intern. Rev. Cytol. (1970).
Makino, S.: A review of the chromosome numbers in animals. Revised edit. Tokyo: Hokuryukan Press 1956.
Montgomery, T. H., Jr.: The heterotypic maturation mitosis in Amphibia and its general significance. Biol. Bull. 4, 259–269 (1903).
Moses, M. J.: The relation between the axial complex of meiotic prophase chromosomes and chromosome pairing in a salamander (Plethodon cinereus). J. biophys. biochem. Cytol. 4, 633–638 (1958).
Pardue, M. L., Gall, J. G.: Chromosomal localization of mouse satellite DNA. Science 168, 1356–1358 (1970).
Schrader, F.: The kinetochore or spindle fiber locus in Amphiuma tridactylum. Biol. Bull. 70, 484–498 (1936).
Scudder, F. W. S.: The spermatogenetic chromosomes of Desmognathus fuscus. Susquehanna Univ. Studies 2, 266–276 (1942).
Snook, H. J., Long, J. A.: Parasynaptic stages in the testis of Aneides lugubris. Univ. Calif. Publ. Zool. 11, 512–525 (1914).
Volpe, P. E., Gebhardt, B. M.: Somatic chromosomes of the marine toad, Bufo marinus (Linné). Copeia No. 3, 1968, 570–576.
Wake, D. B.: Comparative osteology and evolution of the lungless salamanders, family Plethodontidae. Mem. Southern Calif. Acad. Sci. 4 (1968).
Wilson, E. B.: Studies on chromosomes. VIII. Observations on the maturation-phenomena in certain Hemiptera and other forms, with considerations on synapsis and reduction. J. exp. Zool. 13, 345–431 (1912).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Kezer, J., Macgregor, H.C. A fresh look at meiosis and centromeric heterochromatin in the red-backed salamander, Plethodon cinereus cinereus (Green). Chromosoma 33, 146–166 (1971). https://doi.org/10.1007/BF00285630
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00285630