Abstract
Normal synaptonemal complexes (SCs), consisting of two lateral elements and a central element, are present in wild-type, him-4 and him-8 mutant strains in both hermaphrodites and males of Caenorhabditis elegans. Thus, the increase in rate of nondisjunction in the him mutants is not related to aberrant SC morphology. The wild-type hermaphrodite has six SCs, as determined from 3-D reconstruction analysis of serial sections from electron microscopy. Thus, n = 6 and this confirms early reports based on cytological studies with the light microscope. Only one end of the SC is attached to the nuclear envelope while the other end is free in the nucleoplasm and there is no apparent bouquet formation. Either end of the SC can attach to the nuclear envelope. The pairing behavior of the XX bivalent is normal and occurs synchronously with the autosomes. Electron dense bodies, or knobs, are associated with the SC via the central element and displace the chromatin for a distance of 200 nm. Each pachytene nucleus of the wild-type hermaphrodite has six such structures that are randomly dispersed along the bivalents such that some SCs have one or two knobs while others have none. Their function is unknown.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Abirached, M., Brun, J.L.: Ultrastructural changes in the nuclear and perinuclear regions of the oogonia and primary oocytes of Caenorhabditis elegans, Bergerac strain. Rev. Nematol. 1, 63–72 (1978)
Bogdanov, Yu, F.: Formation of cytoplasmic synaptonemal-Iike polycomplexes at zygotene in Ascaris suum male meiosis. Chromosoma (Berl.) 61, 1–21 (1977)
Brenner, S.: The genetics of Caenorhabditis elegans. Genetics 77, 71–94 (1974)
Carpenter, A.T.C.: Recombination nodules and synaptonemal complex in recombination-defective females of Drosophila melanogaster. Chromosome (Berl.) 75, 257–292 (1979)
Choi, C.: Three dimensional reconstruction of quadrivalents and mapping of translocation breakpoints of the mouse translocations T (2:8) 26H and T (9; 17) 138 ca. Canad. J. Genet. Cytol. 22, 261–270 (1980)
Fiske, S.: An adaptation of Reynold's lead citrate for high resolution autoradiography. J. Microscopie 5, 355–360 (1966)
Gillies, C.B.: The relationship between synaptonemal complexes, recombination nodules and crossing over in Neurospora crassa bivalents and translocation quadrivalents. Genetics 91, 1–17 (1979)
Goldstein, P., Triantaphyllou, A.C.: Pachytene karyotype analysis of tetraploid Meloidogyne hapla females be electron microscopy. Chromosoma (Berl.) (in press, 1981)
Hirsh, D., Oppenheim, O., Klass, M.: Development of the reproductive system of Caenorhabditis elegans. Develop. Biol. 49, 200–219 (1976)
Hodgkin, J.A.: Genetic and anatomical aspects of the Caenorhabditis elegans male. Ph. D. Thesis, Darwin College, Cambridge, England (1974)
Hodgkin, J., Horvitz, H.R., Brenner, S.: Nondisjunction mutants of the nematode Caenorhabditis elegans. Genetics 91, 67–94 (1979)
Holm, P.B., Rasmussen, S.W.: Human Meiosis I. The human pachytene karyotype analyzed by three dimensional reconstructions of the synaptonemal complex. Carlsberg Res. Commun. 42, 283–323 (1977)
Holm, P.B., Rasmussen, S.W.: Chromosome pairing, recombination nodules and chiasma formation in diploid Bombyx males. Carlsberg Res. Commun. 45, 483–548 (1980)
Moens, P.B.: Mechanisms of chromosome synapsis at meiotic prophase. Int. Rev. Cytol. 35, 117–134 (1973)
Moens, P.B.: Ultrastructural studies of chiasma distribution. Ann. Rev. Genet. 12, 433–450 (1978)
Moses, M.J.: Synaptonemal complex karyotyping in spermatocytes of the Chinese Hamster. II. Morphology of the XY pair in spread preparations Chromosoma (Berl.) 60, 127–137 (1977)
Moses, M.J., Slatton, G.H., Gambling, T.M., Starmer, C.F.: Synaptonemal complex karyotyping in spermatocytes of the Chinese Hamster. III. Qualitative evaluation. Chromosoma (Berl.) 60, 345–375 (1977)
Mounier, N., Brun, J.: A cytogenetical analysis of sterile mutants in Caenorhabditis elegans. Canad. J. Genet. Cytol. 22, 391–403 (1980)
Nigon, V., Brun, J.: L'evolution des structures nucleaires dans l'ovogenese de Caenorhabditis elegans Maupas 1900. Chromosoma (Berl.) 7, 129–169 (1955)
Rasmussen, S.W., Holm, P.B.: Chromosome pairing in autotetraploid Bombyx females. Mechanism for exclusive bivalent formation. Carlsberg Res. Commun. 44, 101–125 (1979)
Schleirmacher, E., Schmidt, W.: Changes of synaptonemal complex at the end of pachytene. Humangenetik 19, 235–245 (1973)
Sulston, J., Horvitz, H.R.: Post-embryonic cell lineage of the nematode Caenorhabditis elegans. Dev. Biol. 56, 110–156 (1977)
Ward, S., Carrel, J.S.: Fertilization and sperm competition in the nematode Caenorhabditis elegans. Dev. Biol. 73, 304–321 (1979)
Westergaard, M., Wettstein, D. von: Studies on the mechanism of crossing over IV. The molecular organization of the synaptinemal complex in Neottiella (Cook) Saccardo (Ascomycetes). C. R. Trav. Labor Carlsberg 37, 239–268 (1970)
White, M.J.D.: Animal cytology and evolution, 3d edit. London: Cambridge University Press 1973
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Goldstein, P., Slaton, D.E. The synaptonemal complexes of Caenorhabditis elegans . Chromosoma 84, 585–597 (1982). https://doi.org/10.1007/BF00292857
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00292857