Abstract
A comparative electron microscope study at magnifications ranging from about 80,000 up to 800,000 x was carried out in nine species of insects (Gryllus argentinus, Myogryllus verticalis, undetermined species of Gryllus; Blaptica dubia, Periplaneta americana, Blattella germanica; Laplatacris dispar, Aleua lineata and Omexechae servillei). Particular attention was paid: a) to the elementary components of the s. complexes and b) to the structure of their medial ribbon. - a) In all the species examined the basic element found is a curled filament some 15–20 Å thick. Filaments of this kind integrate: the 100 Å fibrils of the chromosome body, the compacts layers of the s. complexes (lateral arms) and the slender planes of the pairing space. The filaments are similar to those described in metaphase chromosomes and their kinetochores (Wettstein and Sotelo, 1965). A difference in density between the filaments of the lateral arms and those of the medial planes is sometimes noticed. - b) Three structural patterns were found in the pairing space. In crickets, the medial ribbon is composed of three parallel, longitudinal planes of filaments, interconnected and connected with the lateral arms by means of bridges. The latter are constituted by fibrils or by single filaments. In cockroaches only two longitudinal planes were found. The distribution of components in these planes follows a plan similar to the one found in crickets. In the electron-micrographs the medial component of both groups of Insecta appears as composed of three (crickets) or two (cockroaches) lines in the longitudinal frontal views, and ladder-like striated in lateral views. The latter striae correspond to filaments or groups of filaments running in antero-posterior direction. - The pattern of structure of grasshoppers differs completely from those mentioned above. Bridging between the homologues is made of regularly spaced transversal planes of filaments. No longitudinal array was observed.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Coleman, J. R., and M. J. Moses: DNA and the fine structure of synaptic chromosomes in the domestic rooster (Gallus domesticus). J. Cell Biol. 23, 63–78 (1964).
Chardard, R.: Recherches sur les cellules-mères des microspores des Orchidées. Étude au microscope électronique. Rev. Cytol. et Biol. végét. 24, 1–148 (1962).
De Robertis, E.: Advances in the ultrastructure of the nucleus and chromosomes. Nat. Cancer Inst. Monogr. 14, 33–56 (1964).
Gall, J. G.: Centriole replication. A study of spermatogenesis in the snail Viviparus. J. biophys. biochem. Cytol. 10, 163–193 (1961).
Guénin, H.-A.: Observations sur la structure submicroscopique du complexe axial dans les chromosomes méiotiques chez Gryllus campestris L. et G. bimaculatus De Geer (Orthopt. Gryll.). J. Microscopie 4, 749–758 (1965).
—, et A. Gautier: Observations sur la structure submicroscopique des chromosomes du Blaps mucronata Latr. (Col. Tenebr.). Rev. suisse Zool. 67, 210–216 (1960).
Maillet, P. L., et R. Folliot: Sur les ultrastructures chromosomiques de la méiose chez ≪Philaenus spumarius≫ L. mâle (Homoptère ≪Cercopidœ≫). C. R. Acad. Sci. (Paris) 260, 3486–3489 (1965).
Meyer, G. F.: A possible correlation between the submicroscopic structure of meiotic chromosomes and crossing over. Proc. Eur. Reg. Conf. on Electron Microscopy, Prague 1964, p. 461.
Moses, M. J.: The nucleus and chromosomes: A cytological perspective. In: Cytology and cell physiology, p. 423–458. New York: Academic Press Inc. 1964.
—, and J.R. Coleman: Structural patterns and the functional organization of chromosomes. Role of chromosome in Development, p. 11–49. New York: Academic Press Inc. 1964.
Nebel, B.R., and E. M. Coulon: The fine structure of chromosomes in pigeon spermatocytes. Chromosoma (Basel) 13, 272–291 (1962).
Ris, H.: Ultrastructure and molecular organization of genetic systems. Canad. J. Genet. Cytol. 3, 95–120 (1961).
Schin, K. S.: Meiotische Prophase und Spermatidenreifung bei Gryllus domesticus mit besonderer Berücksichtigung der Chromosomenstruktur. Z. Zellforsch. 65, 481–513 (1965).
Sotelo, J. R., and O. Trujillo-Cenoz: Electron microscope study on spermatogenesis. Chromosome morphogenesis at the onset of meiosis (Cyte I) and nuclear structure of early and late spermatids. Z. Zellforsch. 51, 243–277 (1960).
—, and R. Wettstein: Fine structure of meiotic chromosomes of Gryllus argentinus. Experientia (Basel) 20, 610–612 (1964)- - Fine structure of meiotic chromosomes. Nat. Cancer Inst. Monogr. 18, 133–152 (1965).
Wettstein, R.: Tridimensional reconstruction of the cyte I nuclei of Gryllus argentinus and Periplaneta americana. (To be published).
—, and J. R. Sotelo: Fine structure of meiotic chromosomes. The elementary components of metaphase chromosomes of Gryllus argentinus. J. Ultrastruct. Res. 13, 367–381 (1965).
Author information
Authors and Affiliations
Additional information
This investigation was supported by United States Public Health Service Research Grant GM 08337 from the Research Grants Branch, Division of Medical Sciences, and partly by Grant RF 61034 from The Rockefeller Foundation.
Rights and permissions
About this article
Cite this article
Sotelo, J.R., Wettstein, R. Fine structure of meiotic chromosomes comparative study of nine species of insects. Chromosoma 20, 234–250 (1966). https://doi.org/10.1007/BF00335210
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00335210