Abstract
A spreading technique was used to allow ultrastructural analysis of seventeen zygotene nuclei of rye (Secale cereale). Twenty pachytene nuclei were also examined. Lateral element lengths of the haploid complements decreased from 742 μm at the beginning of zygotene to 451 μm at the end of zygotene. Variation in pachytene synaptonemal complex lengths was also noted. Zygotene synaptonemal complex formation in rye is characterised by: (1) existence of a bouquet, with telomeric pairing initiation earliest; (2) multiple sites of initiation in each bivalent (maximum of 76 synaptonemal complex segments seen in one nucleus); (3) the potential number of pairing initiation sites may be higher (the average spacing of 4.42 μm would allow approximately 160 sites per nucleus); (4) new pairing initiations occur almost until the end of zygotene; (5) initiation of new synaptonemal complexes and extension of existing synaptonemal complexes occur simultaneously. A simple zipping up of a few initiation sites is not the case in rye. Pairing in different bivalents of a nucleus is not completely synchronised, and the NOR in particular is often late to pair. Interlocking of lateral elements and synaptonemal complexes may lead to delayed completion of pairing in portions of bivalents, but interlocks are ultimately resolved. This resolution may involve breakage and rejoining of lateral elements.
Similar content being viewed by others
References
Abirached-Darmency M, Zickler D, Cauderon Y (1983) Synaptonemal complex and recombination nodules in rye (Secale cereale). Chromosoma 88:299–306
Albini SM, Jones GH, Wallace BMN (1984) A method for preparing two-dimensional surface-spreads of synaptonemal complexes from plant meiocytes for light and electron microscopy. Exp Cell Res 152:280–285
Appels R (1982) The molecular cytology of wheat-rye hybrids. Int Rev Cytol 80:93–132
Bojko M (1983) Human meiosis. VIII. Chromosome pairing and formation of the synaptonemal complex in oocytes. Carlsberg Res Commun 48:457–483
Dresser ME, Moses MJ (1980) Synaptonemal complex karyotyping in spermatocytes of the Chinese hamster (Cricetulus griseus). IV. Light and electron microscopy of synapsis and nucleolar development by silver staining. Chromosoma 76:1–22
Gillies CB (1974) The nature and extent of synaptonemal complex formation in haploid barley. Chromosoma 48:441–453
Gillies CB (1975a) Synaptonemal complex and chromosome structure. Ann Rev Genet 9:91–109
Gillies CB (1975b) An ultrastructural analysis of chromosome pairing in maize. CR Trav Lab Carlsberg 40:135–161
Gillies CB (1981) Electron microscopy of spread maize pachytene synaptonemal complexes. Chromosoma 83:575–591
Gillies CB (1983) Ultrastructural studies of the association of homologous and non-homologous parts of chromosomes in the mid-prophase of meiosis in Zea mays. Maydica 28:265–287
Gillies CB (1984) The synaptonemal complex in higher plants. Crit Rev Plant Sci 2(2):81–116
Hasenkampf CA (1984) Synaptonemal complex formation in pollen mother cells of Tradescantia. Chromosoma 90:275–284
Hobolth P (1981) Chromosome pairing in allohexaploid wheat var. Chinese Spring. Transformation of multivalents into bivalents, a mechanism for exclusive bivalent formation. Carlsberg Res Commun 46:129–173
Holm PB (1977) Three-dimensional reconstruction of chromosome pairing during the zygotene stage of meiosis in Lilium longiflorum (Thumb.). Carlsberg Res Commun 42:103–151
Holm PB, Rasmussen SW (1980) Chromosome pairing, recombination nodules and chiasma formation in diploid Bombyx males. Carlsberg Res Commun 45:483–548
Jenkins G (1983) Chromosome pairing in Triticum aestivum cv. Chinese Spring. Carlsberg Res Commun 48:255–283
Jones GH, Croft JA, Wallace BMN (1983) Synaptonemal complexes in surface spread preparations of orthopteran spermatocytes. In: Brandham PE, Bennett MD (eds) Kew chromosome conference II. George Allen and Unwin, London, pp 123–130
Lima-de-Faria A (1952) Chromomere analysis of the chromosome complement of rye. Chromosoma 5:1–68
Maguire MP (1978) Change in length of synapsed bivalents during pachytene. Chromosoma 69:155–162
Maguire MP (1984) The pattern of pairing that is effective for crossing over in complex B-A chromosome rearrangements in maize. Chromosoma 89:18–23
Moens PB (1968) The structure and function of synaptinemal complexes in Lilium longiflorum sporocytes. Chromosoma 23:418–451
Moens PB (1969) The fine structure of meiotic chromosome polarization and pairing in Locusta migratoria spermatocytes. Chromosoma 28:1–25
Moses MJ (1968) Synaptinemal complex. Ann Rev Genet 2:363–412
Moses MJ, Poorman PA (1981) Synaptonemal complex analysis of mouse chromosomal rearrangements. II. Synaptic adjustment in a tandem duplication. Chromosoma 81:519–535
Rasmussen SW (1976) The meiotic prophase in Bombyx mori females analyzed by three-dimensional reconstructions of synaptonemal complexes. Chromosoma 54:245–293
Rasmussen SW, Holm PB (1978) Human meiosis. II. Chromosome pairing and recombination nodules in human spermatocytes. Carlsberg Res Commun 43:275–327
Stern H, Hotta Y (1978) Regulatory mechanisms in meiotic crossing over. Ann Rev Plant Physiol 29:415–436
von Wettstein D, Rasmussen SW, Holm PB (1984) The synaptonemal complex in genetic segregation. Ann Rev Genet 18:331–413
Zickler D (1977) Development of the synaptonemal complex and the “recombination nodules” during meiotic prophase in the seven bivalents of the fungus Sordaria macrospora Auersw. Chromosoma 61:289–316
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Gillies, C.B. An electron microscopic study of synaptonemal complex formation at zygotene in rye. Chromosoma 92, 165–175 (1985). https://doi.org/10.1007/BF00348690
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00348690